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Prop Governor Issue

BGS

Well Known Member
This weekend I got the pleasure to finally get the engine running. After a couple of cranks it started right up.

However, I cannot get the prop to cycle. Tried a few different times with no luck. I then decided to take the prop back off to see if I missed a plug or something and no luck. Everything was clear. Also when I removed the prop, oil did come out of the hub. Not much, about a cup or so.

Next was to check all the connection and they seemed fine and everything was moving freely.

Last thought maybe Vans sent me the wrong prop - governor combo. Verified that and it is good. Have the HC-2YR-1BFP Hartzel prop and the S-1-32 governor (verified from Hartzel) combo.

So still no luck. Anybody have any suggestions on what to check next?

Appreciate any input on this.

Thanks
Brian
 
I assume you removed the gasket under the governor pad plate and installed the governor gasket with the screen bump on the governor side? The proper gasket seals the holes to/from the gov for oil control flow.

There are picts elsewhere here, I just got back from training and will edit and post some pictures.
 
Good Morning Bill.

From memory I am pretty sure that I did remove the gasket and the screen bump is facing the governor.

Might just have to take off and recheck today.

Thanks
Brian
 
I had the same issue. I had to let the engine run for a minute to get the oil pressure up. So first, make sure you can see oil pressure as the first time you power up, several things need to get filled - this includes the oil cooler, oil lines and the oil filter. Once pressure is up, pull the RPM control, it will take a minute or so for oil to enter. So you will need to cycle it several times to get the oil into the prop and the hub assembly.

Also, did you drill and remove the plug in the crank shaft itself and not just the governor pad?
 
My first engine start required some time before the oil got into the prop. 1700 RPM and give it a few seconds to purge the air out. Do it a few times. Might be worth a try before you begin dis-assembly.
 
Brian,

You're not the first that overlooked pulling the plug for the prop. Having to take the prop off a re-do all that safety wire again is a PITA. Ask me how I know. :eek: The good news is that now that you know what you're doing it goes faster.

It does take some time before you can cycle the governor. I just went through this a few weeks ago myself. After running for a few minutes, increase to about 1700-1800 rpm for a minute or so, then try to cycle the prop. At least that is what it took me to get mine to cycle for the first time.

bob
 
Adjust governor body?

Saw one RV-10 that the governor body had to be rotated to the maximum in the adjustment screws would allow (by rotating the governor body) before the prop would pitch. This was done after first flight when the prop wanted to overspeed.
 
The inner plug should be in the crankshaft for C/S

Your statement: "However, I cannot get the prop to cycle. Tried a few different times with no luck. I then decided to take the prop back off to see if I missed a plug or something and no luck. Everything was clear. Also when I removed the prop, oil did come out of the hub. Not much, about a cup or so."

Probably just a word interpretation thing but "Clear" could mean the inner plug is missing from the crankshaft and the oil is just dumping back into the crankcase instead of driving the prop pitch mechanism.

Bob Axsom
 
Maybe air

Brian -

After seeing your beautiful plane yesterday I got to thinking about this. When we manually moved the prop through it's pitch range, I could hear/feel gurgling, which I don't think I mentioned at the time. That might support the theory that you just need to get the oil flowing.

My governor is different, so I'm not an expert. My $0.02.
 
So with my issue thought I would also make a few calls. Spoke with Vans to verify once again that I had the correct governor prop combo and it is ok. They mentioned to check the plugs also, even the one on the back of the crank that would allow oil to dump back into engine.

Then spoke with Lycoming center that did my engine and they said also to just give it time and should eventually get oil flowing. They also mentioned that I may need to get the RPM's up for the first time. They also wanted me to check that the prop blades could be turned by hand as to make sure there was not an issue there, and they do.

The first tries with this I was running the engine between 1700 and 1900 with no luck. I did try Lycomings suggestion and ran the RPM up to 2000 and nothing, ran to 2200 and it sounded like it wanted to go. With a couple more tries at 2200 it did finally go. Now, it will cycle at 1800 but not below which I am told is pretty normal.

Thanks for everyone's input.

Brian
 
For future builders...prime your oil system BEFORE first engine start. Remove spark plugs(6), pre-heat if wx is cool, fill oil cooler, ground mags, turn prop with starter, have an assistant bleed oil from pressure sender fitting. This will take 30-60 seconds. I have MT governor/Hartzell 2 blade from Van's and my prop will cycle down to 900 rpm, so you may want check into that further. 1,800 does not sound correct.
 
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For those interested, Lycoming SI-1241C, Pre-Oiling Engine Prior to Initial Start, details what they recommend.
 
I had an RV10 recently with a Hartzell CSU that would not cycle under 2000 RPM. Just wondering if there can be a difference between Hartzell and MT CSU's.
 
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I have the two blade Hartzel prop and the Hartzel governor. I run up at 1700 rpm and the prop does cycle. I have never looked to see how low it will go.
 
I'm not a CS guru, but under a certain RPM wouldn't the prop be out of governing range and hitting the stop regardless of where you set the control?
 
Whirlwind CS experience

I had a WW151H on my 6, and now have a WWRV200 on it, I cycle them at 1600 rpm just fine. This always takes longer with the small orifice high pressure Jihostroj governor than with the Hartzell in a Super Decathlon I used to have a share in, just my two cents.
 
The governing band for Hartzell governors appears to be 1800-2700 rpm. My MT governor is 900-2700. I do my runup at 1500-1600 rpm as it lessens my the chances of picking up gravel.
 
I'm not a CS guru, but under a certain RPM wouldn't the prop be out of governing range and hitting the stop regardless of where you set the control?

The governing range as we see varies with manufacturers. On the ground, if I pull my prop control full aft(900 rpm), my engine will not accelerate past 900 rpm upon pushing throttle in. At that low of a power setting, the engine cannot overcome coarsening pitch blade drag as it is coming off of the minimum pitch stops. Now in flight when I go full aft during simulated engine out at 80 kias, it goes down to around 1400 rpm due to the engine being driven by airflow. At this point I am against max pitch stops as the governor senses an "overspeed condition". If we were in a full power dive we may also be up against the max pitch stop and overspeeding the engine at some point. I won't be testing that one out!
 
This is a timely thread as I am getting close to the final fitting of my prop.

When I look down the crank, I see a tube across it with a notch which I assume is something to do with the oil supply to the governor. Behind that, about 6 inches into the crank, I see what looks like a plug in the tube. It also looks like the flange of this plug is on the front side. Hence I see no way I could remove it. Even if I am mistaken and it can be driven out, it's going to end up in the crankcase. Is this what needs to be removed? And if so, how? :confused:
 
No, that one stays in place. The front one (which you don't have) resides almost flush with the propeller flange.
 
So I'm good to go? I assume the oil supply for the prop comes through the cross pipe (about 1/4" with a notch cut out).
 
Still not getting prop to work!

I have a three blade MT with a PCU 5000X prop governor. This unit was run off and on for about an hour on a previously owned engine. So I know that the combo works. I decided to install a Barrett engine and use the same prop and governor.
Can't get the prop to change pitch still! I ran the engine up to 1800 and worked the prop governor lever back and forth for at least 10 minutes. So I removed the governor and checked to see that the gasket/screen was installed the correct way. Then I pulled the prop and looked down the hollow crank. Everything looked good. Also blew air down the opening where the governor meets the mounting flange. It opened up into the hollow crank thru the diagonal tube with the slit in it as it should.
I'm stumped!!!:confused:
Any ideas????
Could the actuating piston in the prop itself have stuck? It's been off the other engine only about four months. It worked great previously.
HELP!!!

P.S. when I removed the prop there was about a pint of oil in the hub that ran out.
 
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I have a three blade MT with a PCU 5000X prop governor. This unit was run off and on for about an hour on a previously owned engine. So I know that the combo works. I decided to install a Barrett engine and use the same prop and governor.

For clarification, were they both installed on a Lycoming 540 before? I had the exact problem with a prop and governor that came off a Subaru and the short answer is that the governor was set to spin the wrong direction for the Lycoming. I had to send it to a shop to change the direction and set the rpm on the governor.

Please clarify.
 
Repeat your 'blow shop air down the oil outlet line' trick, but with the prop on. With normal shop air pressures ( I don't know MT specifics) you should see the blades move to coarse pitch. That will leave the troubleshooting to the governor area.
 
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