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Converting N159SB from FP to CS...the complete story

Brantel

Well Known Member
This thread will serve as a complete record of my efforts to convert my airplane from a Metal FP Sensenich to a 72" Metal CS BA Hartzell.

I want to thank Tim Emig "380mxc" for selling me a new in the box prop. He was a pleasure to do business with and went out of his way to ensure our transaction was painless for both of us. Thanks Tim!

The prop arrived today looking just like it did when Tim sent me the pictures he took right before dropping the prop off at the UPS depot. UPS managed to get it to me in two working days without damage.

Tim also sent me a brand new spinner kit in a separate box. That also arrived in good condition.

I am in negotiations with the Nashville FSDO so hopefully I can get all the legal mumbo jumbo out of the way by the time I am ready to fly this thing.

The goal is to get it installed, fly off the test program and be ready for a trip to Osh. If the plane is not ready or not safe, there will be no Osh for the airplane, I however have alternative transportation available! :D

So tonight I started with getting the Metal FP removed...

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and then focused on getting this plug out of the front of the crank. I used the Don Sword's method to get this plug out. Take a ballpeen hammer with the ball in the center of the plug and then whack it with another hammer. This pushes the plug in and makes the outtie an innie and the plug comes right out. Sounds worse than it is....:p

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I was hoping to not find a plug in the back of the crank but I was not so lucky! Anyone got any suggestions on how to get this thing out?

This crank was reconditioned/certified during the overhaul and had the SB505 done on the inside. While it is slimy in there, I see the epoxy coating is doing its job!

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Next I set out on the task of getting this FP prop/spacer apart so I can ship it to it's new owner.
I used the method provided by the techs at Sensenich to get it apart. I sat the prop on two blocks of wood with a towel cushion. Spinner backplate and spacer in the middle hanging down. I then took a long 3/8" steel drift pin and a hammer and worked back and forth on the dowel pins. Slowly it came apart and all was well. I managed to do this without any damage to anything!

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That's it for today....

For the last 6 months I have been acquiring the parts needed to make the swap....I have the oil line, fittings, cables, brackets, gaskets, studs, rebuilt governor, drive adapter, eyeball, etc. etc. etc.
Hopefully I have everything I need to make this happen in short order.
 
Great job documenting the process, keep the photo's coming, I will follow in your footsteps one day.

Cheers
 
I owed the thread a pic of the new prop!

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Tonight I got started by removing the cowling...

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Next I set out to remove the plug in the rear of the crank that had been installed and then pierced by the engine shop that did the build several years ago.

Here are the tools that it took to get this done!

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Here is the inside of the crank without the plug..

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New plug:

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New plug beside the mangled mess that took forever to get out without damaging the crank or the oil tube that crosses the crank. Lycoming, this is what I call an epic fail for a design!

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New plug installed. This plug is very soft and I started with a soft punch but ended up switching to a wooden dowel to install it without denting it all up. It is difficult to know when the plug is fully seated. It is also hard to keep from damaging that oil tube inside there....

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Next I decided to try and get this plug out....

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I figured it would be very difficult to get this out but it came right out with little trouble.

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Thats all for tonight folks!
 
Today was spinner making day!

Started out with using the spinner backplate doubler to backdrill the rivet holes and to mark the cuttout in for the prop hub in the backplate.

Then It was about an hour's work cutting out the backplate with a Dremel and then much filing with multiple files, sanding with emory cloth and then hitting all the edges with maroon scotchbrite....

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Here is the chunk that gets removed:

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Rivet the doubler to the backplate. It goes on the aft side. Easy peasy with the pneumatic squeezer!

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I layed out the backplate holes with a Cad file and ploted it full size to use to mark the backplate. Worked great!

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Used the template that Hartzell sent me to mark the spinner cutouts for the blades. It was a good starting place but would end up being way too tight...

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Cut em with a Dremel...

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Got started making the little filler plates that go behind the blades. Lots of cutting, filing and sanding.

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Lots of on and off test fitting till I ended up with this. I am sure that there are folks out there that fine tune this to get the closest possible fit. I don't have that kind of time or patience and I do not want the prop to hit the spinner and crack the spinner or mark up the blades so I gave the blades ample clearance!

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That's all for tonight folks! Next is more nutplates....Oh yeah!!!! Oh yeah!!!! Oh yeah!!! :(
 
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The new one is a Hartzell C2YR-1BFP/F7497-2

OH NO!!! 74" will kill you! Don't you know that you can only use a 72" on a tail dragger?? Oh my gawd!! :p

I have the same thing. Vans says no, I say 1 inch per side will give me an extra 30kts... Or something like that maybe. Paint 10kts, leather seats 10kts. Can't wait for the flight report Brian!
 
Haha, While I think a 74" would work OK...this one is a 72". That's what the -2 is all about.
 
OH NO!!! 74" will kill you! Don't you know that you can only use a 72" on a tail dragger?? Oh my gawd!! :p

I have the same thing. Vans says no, I say 1 inch per side will give me an extra 30kts... Or something like that maybe. Paint 10kts, leather seats 10kts. Can't wait for the flight report Brian!

Why do they say that? Seems counterintuitive. (Going 74" too, WW)
 
RV7 74" propeller tip clearance

Brian is correct. BTW I just measured it. Tail down it has 17.5" from tip to ground. Level attitude you have 8" tip clearance to the ground. On the 74 inch prop. Mine is a RV7 though. It's enough for me.
 
Today I finished the pre-install task on the spinner...

I finished these filler parts that go behind the prop.

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Drilled and riveted on all of these nutplates. I hate installing nutplates!

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Backplate finished!

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Next was the awefull task of installing another firewall penetration eyeball. I should have just put this in back when I was building even though at that time I had no idea I would ever be upgrading to a CS.

I need to order another ball. The original steel one I ordered was too small (too small to be drilled even) and this junk box part is too big.

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Hey everybody...check out my Big Blue Knob! :p

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Thats all for today. Not much to show for a bunch of time consuming work!
 
Well I had to take a short break from the prop swap to have some surgery on Friday. I had to be knocked out and have several procedures done to the old pucker string and needless to say this is a pain in the rear!

Anyway I am slowly getting back in the saddle.

Not sure when I did these task but here are the latest updates....

Removed the blank cover that was blocking the prop governor drive adapter hole in the accessory case:

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Spent a ton of time cleaning the old gasket/sealant off of the mounting flange and mounted the prop governor drive adapter. Pics were taken before I cleaned up the excess gasket goop. That blast tube actually goes down the opposite side of the drive adapter and blows right on the fuel pump:

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Installed the studs for the governor in the drive adapter. Figured out that one side of the studs is made to go in tight. Also figured out after trying to bolt on the governor that I screwed the studs in too far. I had to back em all out to match the longer one shown in this pic. This took a long time to get done! I should have put these in before mounting the adapter.

Put the gasket goop on the gasket and mounted the governor.

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I decided to take the over the top route for my prop oil line. I installed the steel fitting in the front of the case:

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Couple of adel clamps to secure the hose:

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Hole in the baffle with edge gripping grommet stuff. This will get sealed with red silicone.

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This over the top method seems to be going to work out well The length of the hose seems just about right. I have too much other stuff running where it would go in the lower path and did not want to hack up my baffles in front of the cylinder to make a hole for the hose.
 
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I also installed the prop control cable using Van's bracket and hardware, adjusted it so the lever hits the stops and mounted the governor.... I installed the cable on the bracket/governor beside the engine before worming it back into position.

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I am hoping this governor works. It is an old Woodward unit that was suppose to have been rebuilt were it matters. I only paid $400 for it and the drive adapter with a brand new gearshaft so if it does not work, I am not out much. I took a peek inside when I was reclocking the lever and it seems clean inside with nothing obvious out of place or worn out. Fingers crossed! If not, I have my finger cocked and ready to order a PCU5000X....

Thats all for now folks....
 
...I finished these filler parts that go behind the prop...

Too late for you to consider, but I just re-made these pieces because on my last condition inspection I ran the engine up without the spinner and one of them departed the aircraft at high RPM. Anyway, when it left, it tore out all the rivet holes on the backplate and made quite the mess. So I made these pieces out of .016 aluminum and secured them with the three mounting screws. The filler pieces simply are trapped between the backplate and spinner, located by the three screw holes - no rivets at all. They seem perfectly happy after a year of flying and as a bonus are completely out of the way with the spinner removed.

Maybe someone else can try it - I like it.
 
Started to mount the prop and ran into this issue covered in another thread:

Need an answer on what to do about my prop bushings sticking too far out past the flywheel.

I am trying to mount my new Hartzell CS on my plane and noticed that the oddball prop bolt bushing is sticking too far past the flywheel and there is no counterbore for it on the prop flange.

What to do?


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I decided to take this path to avert the crisis: Pushed it out and filed it off a little and put it back....

Did a ton of research on this and the following document : http://www.lycoming.com/support/publications/service-instructions/pdfs/SI1098H.pdf

and I feel happy with what I did. The bushings are correct for my engine, just a little tolerance stackup I think.

other info I learned during the process:

The fishy thing is that one company made the crank, one company made the flywheel, one company made the bushings, one company made the prop and another company inspected, reworked and yellow tagged the crank. Oh and all of this stuff happened with a total span of about 50 years.

The new CS is a R flange prop. The crank is setup as a K flange crank. The Hartzell manual says that a R flange prop can be installed on a K flange crank or a R flange crank. This was never an issue before because the FP spacer has counterbores all the way around it on the back. The new CS prop has one bolt hole that has no counterbore and it must be installed in one of 2 locations on a K flange crank. My bushings just happen to sit a little proud in those to locations. I was super cautious when installing and noticed this. Not sure if someone in a hurry would have even noticed it.

I was looking at the work order from Aircraft Specialties and they did do the oil seal area repair to this crank.

No threads were removed during this grinding operation. Only the area in front of the threads was ground down and re-chamfered..

I have inspected that document and see that one of two part numbers may be installed in the position F in question and those two part numbers vary in length by 0.006". They are the same otherwise. It is possible I guess that I have the longer of the two.

The other 4 appear to be correct and fit the prop flange nicely. The one in position C opposite F is also the correct diameter but was a little proud as well. This did not matter however because the prop flange is counterbored in position C.

The bottom line is that it looks like everything I have is correct with the exception of the length of the two bushings installed in position C and F. Those were a little proud of the flywheel. The others have positive engagement with the counterbore of the prop flange as specified in the Service Instruction No. 1098H.


So we proceeded with the install of the prop:

I had two helpers and myself to do this hang job. You must try and get all the bolts started a little bit and this can be a challenge. Two helpers really help as long as only one guy is doing the driving....make sure you put the flywheel and the alternator belt on first!

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The oil dripping is where I lubed up the oil seal and oil seal part of the crank.

It is critical that the prop be clocked properly to align with the correct bushings in the crank.

Get em started and then turn in em a little at a time making sure to keep everything as square as possible.

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Prop hung with bolts snug:

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Helpers were exhausted...

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This thing is worth its cost! Works great for initial install and torquing of the bolts.

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I followed the Hartzell manual to torque all the bolts in the order specified to 40ft lbs and then all to 70ft lbs.

Next is the safety wire. I am using 0.032" per the manual. I needed to research how in the world this is possible when one of the pairs ends up with the roll pin radial to the hub. There is no way to get the wire in the reverse hole without moving the nut. So I plan to follow the many post here in the archives and loosen the nut a bit, put the wire in and then torque it back to spec. That is next....


Thats all for now folks!
 
...Next is the safety wire. I am using 0.032" per the manual. I needed to research how in the world this is possible when one of the pairs ends up with the roll pin radial to the hub. There is no way to get the wire in the reverse hole without moving the nut. So I plan to follow the many post here in the archives and loosen the nut a bit, put the wire in and then torque it back to spec. That is next....

I have never had to loosen/torque the nuts to lock wire. It just requires some up front planning.
 
I have never had to loosen/torque the nuts to lock wire. It just requires some up front planning.

Well do tell cause I ain't seeing it....I was a UH60 helicopter mechanic in the Army and used to think I could safety anything till I ran across these prop hubs....

I would love to do it without messing with the nut.

It seems that some people get lucky and the roll pin ends up in a spot where you can get the wire in on the inside of one of the nuts. I got unlucky and most of mine are pointing radially toward the hub.
 
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Thanks to the extra motivation Alton gave me to give it an honest effort, the safety wire complete! Total time to install = 35 minutes...

In the end I only had loosen and re-torque only one nut. There was just no way that one was going in due to the way it was pointing. I was able to plan ahead on the others and find a combination of adjacent nuts that would allow me to make it happen.

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From the Hartzell Manual:

Torque the 1/2 inch propeller mounting studs (dry) in accordance with Table 3-1, Figure 3-1, and Figure 3-2. Safety wire the studs in pairs (if required by the aircraft maintenance manual) at the rear of the propeller mounting flange. Refer to Figure 3-6

"My" aircraft maintenance manual does not call out safety wire :eek:

I check the torque at each annual and remove the prop every few years to clean out the hub and inspect the electronic ignition crank sensor board.
 
From the Hartzell Manual:

Torque the 1/2 inch propeller mounting studs (dry) in accordance with Table 3-1, Figure 3-1, and Figure 3-2. Safety wire the studs in pairs (if required by the aircraft maintenance manual) at the rear of the propeller mounting flange. Refer to Figure 3-6

"My" aircraft maintenance manual does not call out safety wire :eek:

I check the torque at each annual and remove the prop every few years to clean out the hub and inspect the electronic ignition crank sensor board.

Thanks Walt, I saw many post arguing this back and forth. I just feel better with em tied although I really don't think they would ever go anywhere in a million years.
 
Those other bolts seem to have quite a stack of washers under them. To get the nut above a non threaded area?

Nice work, as usual!
 
Those other bolts seem to have quite a stack of washers under them. To get the nut above a non threaded area?

Nice work, as usual!

Apparently this is because Van's request long bolts on their prop orders and this is to prevent the nut from bottoming out on the bolt shank. It is in the directions to do it this way so I followed them.
 
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Bad news....no test flight today!

Test ran the engine and the used governor that I purchased operates backwards. Push the knob in and it goes to course pitch, pull it out fine.

It must be setup for a counter weighted pressure to decrease pitch prop. :mad:

Moral of the story...never trust anything when it is used. I tried to figure out the part number before I bought but could never find the details on the number. I don't think the guy that sold it to me knew it was incorrect. I think the guy that sold it to him possibly him knew it was....

I bought it with the drive adapter with a brand new gear for less than those parts go for used so I am not out much $... I figured it was worth the risk and now I have to find a good governor.

I have a lead on a used PCU5000 but I trust this guy 100%.
 
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Well thanks to Jerry "Widget" Morris, I have a used PCU5000 on the way.... Not everyone can say they have parts on their plane that were used on planes flown by Team Aerodynamics!

Lucky for me the team recently swapped props and governors and Jerry saw my need and contacted me with his used one for sale.

New gasket on the way from ACS and the governor should be here Wednesday at the latest....



Here is what I did Saturday before the big test run...

Got started by finishing the safety wire on the main prop bolt nuts.

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Then installed the front spinner bulkhead and drilled the spinner to match the holes in the bulkhead. Removed the bulkhead, installed the nutplates, reinstalled for good and safety wired the bolts.

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Finished the install on the flexible prop oil line. Torqued the fittings and striped em with torque seal...

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Same for the other end on the gov. dang, there is more gasket goop!

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After the test run and figuring out the governor was not going to work, we set out to re-weigh the bird. Scales in the background. Yes I did put the cowl back on before the weighing!

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She ain't no light weight with a full IFR panel, backup battery, and now a metal CS prop. but my empty CG is now much better!

79.97" empty now! Woohoo! I had hoped to get to at least 80" empty so I reached that goal!

Until the governor and gasket get here, thats all folks!
 
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woodward governor

Bad news....no test flight today!

Test ran the engine and the used governor that I purchased operates backwards. Push the knob in and it goes to course pitch, pull it out fine.

It must be setup for a counter weighted pressure to decrease pitch prop. :mad:

Moral of the story...never trust anything when it is used. I tried to figure out the part number before I bought but could never find the details on the number. I don't think the guy that sold it to me knew it was incorrect. I think the guy that sold it to him possibly him knew it was....

I bought it with the drive adapter with a brand new gear for less than those parts go for used so I am not out much $... I figured it was worth the risk and now I have to find a good governor.

I have a lead on a used PCU5000 but I trust this guy 100%.

dont throw the governor away, theres nothing wrong with it....I think.
theres two plugs on the body of the governor side by side remove the plugs and thats where the adjustment is for pull or push. a prop shop would take about two minutes to switch it around for you.had to have my governor set up for my van,s prop on my RV6 afew years ago...It,s a very easy quick job. my prop guy showed me how it,s done but my memory sucks...search the net...
just called myprop guy...2 plugs on side of governor secured with safty wire..remove both plugs..inside one will have another plug with hex head...remove hex plug and insert in other hole.. replace plugs and safty wire.....job done...push or pull depends on which one has the hex plug in it...
 
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dont throw the governor away, theres nothing wrong with it....I think.
theres two plugs on the body of the governor side by side remove the plugs and thats where the adjustment is for pull or push. a prop shop would take about two minutes to switch it around for you.had to have my governor set up for my van,s prop on my RV6 afew years ago...It,s a very easy quick job. my prop guy showed me how it,s done but my memory sucks...search the net...
just called myprop guy...2 plugs on side of governor secured with safty wire..remove both plugs..inside one will have another plug with hex head...remove hex plug and insert in other hole.. replace plugs and safty wire.....job done...push or pull depends on which one has the hex plug in it...

I will look at it but I don't remember these plugs....I have tried to find info on these govs online and have came back with little data. I am pretty good at finding what I need online but there does not seem to be much out there on these old governors.

I will feel much better with the PCU5000 anyway so I will sell this one to someone else with full disclosure. It seems to work fine, just backwards. I will however take a look and see if this plug thing looks doable.

Thanks!
 
Well I finally got "Concurrence" of my proposed Phase I flight test area from the local FSDO. The proposed area was the same as my original Phase I test flight area.

The following goes to show how different the various FSDO's are and how they handle us EAB guys.

I was told by a FSDO inspector that "Most people just make these prop swaps and never contact us. I have never had anyone inquire about switching from a FP to a CS prop."

A very well used local DAR told me "Brian, I agree with *****...most folks put themselves back in phase 1 for 5 hours, make the appropriate logbook entries and press on. I have been of the opinion that the notification to FSDO is for information only with amateur built aircraft changes since you are the builder/technician of an experimental aircraft, not a type certificated machine."

Obviously neither of these folks have ever actually read the Operating Limitations that they are handing out to people because they are pretty clear on what must be done. It is my opinion that ignorance is not a defense and if something goes wrong, guess who is on the hook?

I got the impression that the FSDO and the DAR thought I was a moron for following the rules.... Very frustrating!

The good news is that my PCU5000 should be here today!
 
So they tell you to inform them of changes, but there is no corresponding inspection/review by the Feds to "ensure safety"...

...and now it appears the CYA aspect isn't valid either.

Is there any wonder why people don't follow the rules?
 
Brian,

For what it's worth, when I changed from one Harztell c/s prop to the newer BA model, I followed my Operating Limitations and called the Orlando FSDO. The guy was very knowledgeable and suggested exactly what yours did, just use your original Phase I area, fly a 10-hour phase I and make the required logbook entries. No need to call me back. I was pleasantly surprised at this guy's professionalism and knowledge of EAB procedures.
 
wire....

Well do tell cause I ain't seeing it....I was a UH60 helicopter mechanic in the Army and used to think I could safety anything till I ran across these prop hubs....

I would love to do it without messing with the nut.

It seems that some people get lucky and the roll pin ends up in a spot where you can get the wire in on the inside of one of the nuts. I got unlucky and most of mine are pointing radially toward the hub.

Well... another old Blackhawk mechanic here.... As much practice as we get doing the safety wire dance, it always helps to have the right tools. I've never had to loosen bolts to safety them. The trick is to go to the YARD STORE (google "yard store aircraft tools") and order their safety wire tool. It has a screw driver handle and two small holes for the safetywire to fit into on the tip. You will also need a set of pics to get a hold of the safety wire as it pokes through the other end.


PN: 13710
"6" Manual Safety Wire Twister
Excellent tool for getting into those hard-to-reach, tight areas. Twists up to 0.060 wire."
They also offer a longer one but I've never had to use it.
Best of Luck!!!!
Respectfully,
Brian Wallis
 
Thanks Brian, That tool looks interesting.

I really don't have any issues twisting wire. Had little to no trouble getting the wire thru the roll pin, around and out from behind the nut when the wire was inserted outside to inside, its the other direction on the opposite nut that is the issue. No pick or twister is going to help get that wire in the hole and threaded thru the roll pin when it is aligned radially to the center of the hub. Some correctly curved forceps might have helped but I did not have any.
 
FSDO

I contacted the San Jose FSDO for concurrence on my engine and prop change, and the reply I got back was "it's really an honor system thing.... but yeah, I concur." Printed, added to the log binder. Kinda of strange, but I'm not going to argue.
 
The new to me PCU5000 arrived last evening so I got to work today on removing the Woodward and installing the PCU5000. Too bad for me COPILOT001, this one did not have any plugs in the side to swap operating modes... I contacted the new Woodward folks and they sent me the specs on the unit I have. It definitely was setup for a counter weighted prop.

Anyway it took quite a while to get the few day old gasket cleaned off the drive adapter. Turns out I was using the wrong gasket. The Lycoming gasket is only for the blank cover and is not to be used with the governors. Found this out too late. The governor needs to be used with a rubber type gasket that has a screen in it to trap stuff that could jam the pilot valve.

Incorrect Gasket:
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Correct Gasket:
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New gasket installed, I set forth to swap the control cable and bracket over from the Woodward to the PCU5000. Easy enough...

Problems started when I tried to mount the PCU5000. Since it is much shorter than the Woodward, the bracket was dead centering one of my oil cooler lines. I spent the next several hours trying to get the -8 45° fitting out and swap it for a straight one. NO JOY, that fitting ain't budging! I wrung a 3/8 extension in half after 30 minutes of heat from a heat gun and the thing still did not move a millimeter.

Gave up trying to get that fitting out so I decided I may try one of those 45° angle adapter fittings (would have to order) so while I had the oil line loose, I mounted the governor to take a look for clearance when I realized that the oil line would go behind and around the control bracket just fine so that is what I ended up doing. The control bracket centers the hoop created by the hose. Nothing rubs so I am good with it.

Was thinking about using this to get the hose out of the way, in the end I did not need it:
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So I cleaned up all the mess and there was a big mess from all the oil dripping from the governor drive pad, the governors, and the oil filter and filter mount all of which had to be removed to get the job done.

Reinstalled everything and pushed it out for a test run and to check for leaks. The test run went very well. The PCU5000 works as expected. No leaks.

I tested the flat pitch stop by a few short full throttle blast and I was overshooting 2700 so I pushed her back in the hangar and removed the spinner and gave the low pitch stop 1.5 turns in. Put it all back together and pushed it out for another test run.

After adjusting the low pitch stop, quick full throttle blast resulted in about 2650 rpm so I am good with that. I tested the governor and cycled the prop a few times and it all appears to be working fine.

Looked for leaks again and found none.

Had to leave the airport so no test flight tonight. Earliest a test flight can take place now is Saturday morning.

Looks like I am going to Osh with a raw unpainted spinner since I can't test fly and paint at the same time....I don't want to run without the spinner in place. Too many reports of the filler pieces flying off.

Bible school all week this week, issues with the Woodward governor and my surgery last week and recovery have really compressed my schedule!
 
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I was having trouble with the static run up testing. The tires were sliding/hopping on the pavement....:D

Don't nose it over on a full power ground static run! That would really stink. When we first ran up my buddy's newly-built RV-8 with ECI Titan IO-360 and Hartzell BA prop, we tied the tailwheel to a pickup truck bumper and it felt like it wanted to drag the truck along! We had two guys holding the tail down too.
 
Be ready for two right rudder events: one when you do your initial throttle up with more rpm than you had with the fixed pitch, and the second when the blades start to get "governed" and bite more, a few seconds down the runway. It takes getting used to but it sure is fun:D

After a few of these, you won't notice it.
 
...I tested the flat pitch stop by a few short full throttle blast and I was overshooting 2700 so I pushed her back in the hangar and removed the spinner and gave the low pitch stop 1.5 turns in. Put it all back together and pushed it out for another test run.

After adjusting the low pitch stop, quick full throttle blast resulted in about 2650 rpm so I am good with that. I tested the governor and cycled the prop a few times and it all appears to be working fine...

The pitch stop is only that - a "fixed" stop for the blade angle. You may have adjusted it to give you 2650 on the ground, but all you've really done is create a "ground adjustable" fixed pitch prop (set to very fine pitch, at that). As soon as you get some forward speed (or different temperature, altitude, barro setting, ect.) it will quickly overrun that setting and the RPM will increase until the governor finds its setting and decides to join the party. That may be 3000 RPM for all you know. It's the governor you should be looking at. As an RPM based device, if the governor is not "governing" the RPM at 2650 static, don't expect it to in flight either. Might not be a problem, but be prepared for some RPM higher than 2650 halfway down the takeoff roll.

Keep you hand near the blue knob... you might have to give it a few turns on takeoff. Or better yet, just plan to abort the first takeoff. You should get a "governor surge" a few seconds into the roll, and the RPM it settles at is going to be what you can expect in flight. I suspect that your RPM is going to settle in higher than 2700 considering that your initial setting was pitch stop limited - meaning the governor was not even thinking about getting involved even at 2700.
 
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The pitch stop is only that - a "fixed" stop for the blade angle. You may have adjusted it to give you 2650 on the ground, but all you've really done is create a "ground adjustable" fixed pitch prop (set to very fine pitch, at that). As soon as you get some forward speed (or different temperature, altitude, barro setting, ect.) it will quickly overrun that setting and the RPM will increase until the governor finds its setting and decides to join the party. That may be 3000 RPM for all you know. It's the governor you should be looking at. As an RPM based device, if the governor is not "governing" the RPM at 2650 static, don't expect it to in flight either. Might not be a problem, but be prepared for some RPM higher than 2650 halfway down the takeoff roll.

Keep you hand near the blue knob... you might have to give it a few turns on takeoff. Or better yet, just plan to abort the first takeoff. You should get a "governor surge" a few seconds into the roll, and the RPM it settles at is going to be what you can expect in flight. I suspect that your RPM is going to settle in higher than 2700 considering that your initial setting was pitch stop limited - meaning the governor was not even thinking about getting involved even at 2700.


Thanks Michael,

I have been doing much studying on the subject of the fine pitch stop and found many post here from folks that are very much prop experts. I also have found common requirements in the manuals for both the governor and the props to ensure that the fine pitch stop is adjusted correctly and ways to determine whether or not your on the fine pitch stop and or if the governor is doing the work.

Keep in mind that this governor came straight off of one of Team Aerodynamics airplanes and was adjusted and working perfectly when removed. The High RPM stop screw should be pretty close but I understand there will be minor deviations between props and engines.

The governor was working just fine during my test when given time to catch up to the fast changes in power. The initial overshoot was quickly brought back down to 2700 rpm if I gave the governor time to react. The purpose of the fast short power changes is to set the proper location of the low pitch stop ensuring the governor is not in the way. I understand that the other way to do it is to watch the RPM on takeoff with a fast application of power.

During my second test run after adjusting the fine pitch stop, I also ran up to 2650 static and gave the blue knob a turn or two out and after about a 1/2 turn it started reducing RPM so I know it is close.

Many very knowledgeable people including the manufacturers include setting the low pitch stop properly as a requirement for these installs. Most if not all recommend 2600-2650 as a target for fine pitch static RPM MAX and to use the flat pitch stop not the governor for this adjustment. They claim that doing so will reduce the amount of surge you get on takeoff and optimize/reduce drag in the event of an engine failure. It also ensure that in the event of a governor/cable failure that the prop will be able to provide enough thrust at red-line to fly the plane. It may also help prevent costly engine overs-peed events if a short term loss of oil pressure is experienced.

The common point that seems to be made in all the "official" stuff I have read:

MAX Static RPM is set by the Fine Pitch Stop on the propeller. (as long as the governor does not catch it first...)

MAX in flight RPM is set by the High RPM Stop on the governor.

Here is a quote straight from the governor manual:

"GENERAL

Static Run-up


There has been some confusion in the field concerning propeller low blade angle setting, the governor setting and how it relates to static run-up and take-off RPM.

As a general rule, engine redline RPM cannot be reached during a full power static run-up.
Contrary to popular belief, the governor is not controlling the propeller at this time, the propeller is against its low pitch stop. Attempting to increase propeller static run-up RPM by adjusting the governor high RPM screw will have no effect and will probably result in a propeller overspeed during the take-off roll."


Other pertinent postings:

Hi Jim,

The light weight blades on the whirlwind (and MT) propeller allow the engine to respond almost directly to the throttle position. If the throttle is set to a position that gives 1200 RPM, when the engine starts it will be running at 1200 RPM.

The propeller low pitch stop should be set give a static RPM of between 2600 to 2650 RPM.
This is not my opinion. This is a safety of flight issue.

The governor low RPM setting controls the engine RPM after the propeller blades come off of the propeller low pitch stops. This would happen very early in the takeoff roll.

Jim Ayers
MT Propeller distributor
FAA Propeller Repair Station # [FONT='Arial','sans-serif']LDSR535X[/FONT]

Yes, setting the low pitch stop properly is the best way to prevent or minimize RPM overshoots during max power static/takeoff conditions. I normally set the low pitch stop for 25-50 RPM below rated RPM during a max power static run-up. I do this by starting at a high angle and running a series of decreasing blade angles to develop a relationship between blade angle and RPM. This allows me to pick an angle that includes the factory assembly tolerance on the low side. This should minimize or prevent any RPM overshoots during static/initial takeoff throttle slams. It will do nothing for you in flight since the prop is off the low pitch stop at ~40 kts.

I realize this would be difficult for someone that doesn't have the tools to measure blade angle, so I would recommend you first confirm the governor high RPM stop is set properly in flight, say 2700. Then I would start increasing the low pitch stop setting during a series of max power run-ups until you see it drop just below the max rating. I understand max power run-ups on lightweight RVs carries some risk so you might want to do this iterative process by noting RPM overshoots during normal takeoffs. You can increase the low pitch setting a little each time until the overshoots diminish or go away entirely.

Yes, ambient conditions will affect your results. Do this on a low/cold day and you are likely to set the angle a little high; on a high/hot day you will probably be a little low. If you are turbocharged it gets more complicated...

The low pitch stop adjustment on Hartzell props is very easy. The procedure is in the Owner's Manual 115N. I'm not familiar with how the WW low pitch is set or even if it can be adjusted on-wing?

The low inertia of composite props increases the likelihood of overshoots; they spin-up faster making it harder for the governor to catch it before exceeding the high RPM setting.

I have an example chart I can share once I figure out how to post/attach it to a message.

Les Doud
Hartzell Propeller
 
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From a man that experienced an expensive overspeed event...
Actually, it would be better if you couldn't quite get 2700 rpm early in the take-off roll. If you can get 2700 rpm in the early part of the take-off roll, your low pitch stop is set finer than it needs to be. This would increase the windmilling drag during an engine failure, and increase the rpm that the engine will go to if the prop governor ever fails, or if you have a loss of oil pressure. According to Hartzell, during a full power static runup, the rpm should be somewhere between 2650 and 2700.

I believe that it is best to have the low pitch stop no finer than it needs to be. If the low pitch stop is set to give 2650 rpm in the initial part of the take-off roll, the rpm will increase as the speed increases, and you should have 2700 before the aircraft becomes airborne.

I'm a technical representative for Hartzell, so I thought perhaps I could be of some benefit.

When you are setting your low pitch stop, you want to set it about 50 RPM below max. RPM, so if you have a max RPM of 2700, set the low pitch for 2650 static. You will get 2700 (or perhaps more) shortly into you takeoff roll, as the prop ?unloads? and the airstream enters the prop.

Setting static RPM is a "normal" propeller installation task, even on certificated aircraft. On the Van's aircraft, the horsepower output of the engines can vary widely, so it is even more important to do a static RPM check, and adjust the low pitch stop as needed.
 
Thanks Michael,

I have been doing much studying on the subject of the fine pitch stop and found many post here from folks that are very much prop experts...

Ok, sounds like you have a handle on the situation... Glad to hear it!
 
Initial Flight Test Complete....

Prior to today I made sure my logs were up to date. The correct entries were made to place my airplane back into Phase I, updated W&B was placed in the airplane, the Operating Limitations were swapped out etc.

After safety wiring the oil filter, giving everything a triple check, reinstalling the cowling, checking the air pressure in the tires, fuel was put back in the plane etc. etc. etc.

First test flight completed this morning. :D

The flight was short due to having to leave early for family time a little over a half hour.

I kept it close in due to the amount of work I did. Ceiling was 1300-1400' so I just blasted around in circles climbing and diving and checking operation of the governor.

ienfbp.jpg


On the takeoff, the RPM was just about perfect on the quick power change shot up to ~2650. Once the airspeed built and the governor caught up, the max RPM was 2680. This tells me that I am close on my adjustments. I may tweak the governor high speed stop screw a touch to get on up to 2700-2710.

Click for bigger version:


Coming from a FP the CS is a major rush. It is almost like a whole different airplane. The takeoff roll was much shorter, the acceleration is just a blast, the climb rate was amazing, the airplane slows down instantly when you pull the power back, the float in the flare is reduced, landing roll is less etc. etc. etc.

Oh and I am at least 10kts faster! ;)

I think I am going to like it! :p
 
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Fantastic! You need to update your .sig on your VAF profile now too ;)

Wish I could afford to convert mine, now that I discovered the crack in my wood prop today.
 
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