No pitch change on Hartzell

[Don Patterson]

At first engine start the new Hartzell prop would not change pitch. I ran the IO-360 B4A engine 5 times at 1800 to 2300 rpm's with no luck. I pulled the PCU 5000x for testing at a local prop shop and checked out fine. I tested all lines and gaskets for oil passage and this checked out fine. I placed an oil filled pressure gage at the fitting just behind the prop and was getting 310 pounds of oil pressure from the governor every time I cycled it. I pulled the prop to inspect the rear plug in front of the crankshaft and it was in place.
This IO-360 B4A was overhauled about 5 years ago but was run with a fixed pitch. This is the first time with a C/S prop. The mechanic had passed away a few years ago. I am thinking something was overlooked at overhaul. I know the same case was used.
I put 80 pounds of air in the fitting behind the prop to get some pitch change (per prop shop) and it would change but not very much. Most of the air was just going into the case. Sounds like all of the oil from the governor is just going back into the case. Has anyone had a similar problem?

[gereed75]

There is a small port in the left crankcase half that is used to port oil back to the crankcase on engines that came with solid cranks. This port must be tapped and fitted with a 1/8 pipe plug.

ECI has tech bulletins out on this. Lycoming does not. Google "ECI fixed pitch conversion" or similar and you might find it.

Bad news is that the cases must come apart to make this fix. I posted some additional info in a previous post just recently. Search the forums for "constant speed conversion" and you might find it.......

Just found the previous thread entitled "CS Prop". Sorry don't know how to link it.

[apkp777]

Don, sorry to hear you having troubles. If you guys need any help tearing it down give me a call I and I'd be glad to lend a hand.

gereed75 is probably correct on what it'll take to get it fixed. The good thing is, it's an easy fix, just gonna take some time.

[Bob Martin]

Don,
I had the same thing happen to me on a FP to CS upgrade on a A1A.
It had been running for 600 hours with a FP prop.
I know where you have been and where you are going....it is not an easy thing to take. The worst part is, you think you are ready to fly with a new fancy prop and then you get hit in the gut that you will have to completely tear everything apart!! geezzzz.
Anyway, watch and look for anything that might be the problem when you disassemble it. My problem was actually that the front thrust bearing was out of place and was not seated over the dowel in the case half and that allowed oil to flow under the bearing and back to the sump. So don't just assume it needs a hole plugged. On the bright side, you get to see inside your engine!
ohhh...and you will LOVE the C/S prop......:-)
Good Luck!

[gereed75]

This is a little known problem, and as a result is likely to happen to those making this conversion (solid crank FP to hollow crank CS). Everyone does the commonly known internal crank plug thing, but this is easy to miss. I know personally of one other instance.

Maybe DR could sticky this thread in the traditional engine forum and give it some notoriety. If it saves one un-necessary engine pull/teardown it would be worth it.

Good Luck Don.

[N130WN]

Ya, sounds familiar.

http://blog.bowenaero.com/?p=59

[panhandler1956]

Man you guys are making me nervous! I bought a used IO-360-A1A (200SMOH) off a flying Pitts S1S, but was set up as fixed pitch and I'm in the process of converting it to CS (see previous post). In this engine's history it needed new cases and DivCo supplied the yellow tagged cases, but I have no idea if they have this mysterious bypass.....I'm thinking about asking Lycoming using the serial # of these cases to see if I can get some reassurance before I figure it out on the first engine start up!

[Jetj01]

Last May '09 my newly overhauled O-360 A1A had to go back to the engine shop because that port was left unplagged during the engine case overhaul prior to re-assembly. Unless specifically told to do so, they will leave it open if it is to be used for a fixed pitch install. I had my RV-4 all done (I thought!) and had to remove the engine and wait the three weeks and $$$ to get it spilt and fixed and re-assembled and sent back to me. Sucked but necessary!

And yes, this is a little bit of unknown info and so DID remove the prop governor, had it checked, bought a new one anyway, still didn't work, etc....

Big relief when I had it all back together and it worked! BTW, I bought the same PCU-5000X prop governor you have now to replace the Woodward I thought was not working. I works better than any I've flown behind before. Rock solid, even during acro! LOVE IT!!!

Tailwinds,

[gereed75]

Yikes JJ, Your story exactly echoes mine - 2 - 3 weeks trouble shooting, s**tcan the probably good woodward govenor, buy new PCU (yep, its a keeper), more troubleshooting. Finally found the "fix" on the ECI site. Engine off, teardown and reassemble (and of course re-doing half the stuff FWF "better" the second time).

I hope this thread saves someone that hassle!!

Brent - do an air pressure check as Don described. You might be able to confirm if this port is there in your engine by tracing S/N or model numbers, but the air pressure check will confirm.

Well I said that I personally knew of one other instance, now JJ makes three, Don probably four, Larry makes five. I got my fingers crossed for you Brent!! At least you won't go through the troubleshooting and govenor R&R cycle!

c'mon Doug, stickie this thread!!

[Danny7]

Gary you can link other threads by just cutting and pasting what is in the address bar. the website makes the link hot automatically

this is the thread gary mentioned in his first post:

http://www.vansairforce.com/communit...ad.php?t=26036