Prop Governors..

SoCalPlaneDoc

SoCalPlaneDoc

New member
All the C/S props I've owned have been trouble free so, even as long as I've been wrenching on planes, governors are still a magic box to me. I mean, I know the basics on how they work and such but..

Just finished removing and replaced the prop cable. It was jammed so tight I couldnt move it, cleaning it fixed that. Put it back on taking great care to put it back exactly the same, verfied that arm on the governor still moved to the same spots.. figured that'd be it but NOW at full fine it's 150 rpm lower and when I throttle up, it's hit's it's max, drops a little, then returns to it's max. it never did that before.

I'm thinking something changed with the governor weights but find it suprising that it would happen suddenly and coincidentally to me cleaning the cable..

what do you guys think?
 
Sounds to me like the cable is moving. I know on mine it is impossible to see with the nose bowl on. It is always the simple sh*t that gets you. If you freed up the cable and the problem just started it is in the cable. Lynn the crate :?
 
lwford said:
Sounds to me like the cable is moving. I know on mine it is impossible to see with the nose bowl on. It is always the simple sh*t that gets you. If you freed up the cable and the problem just started it is in the cable. Lynn the crate :?
Click to expand...

ya, it's not the cable. the governor is all the way to the hard stop. even wired it there and ran it up just to see.. cable is good.
 
OK, you have eliminated that so now it looks like the Gov. is your next move. Oil controls the prop pitch and the Gov. controls the oil. Pull the Gov. and check the gasket screen, it should be clean. If it isn't that ,it is a bigger problem. I would send the Gov. to a good shop and they will test and overhaul with a 8130 tag. I believe you have an IO-470. This has the infamous oil control collar that can be difficult to diagnose if that is the problem. That is the last thing you want to do. Simple stuff 1st. Press on, the problem is in there somewhere, and you will find it. :!: Lynn the crate
 
When was your governor last overhauled? Mine started doing the same surging thing a year or two ago and we finally sent it in for overhaul last year which fixed the problem, although it does seem like an odd coincidence in your case. There's a shaft in the Woodwards on the -3s that apparently has some wear issues and I definitely got a lecture on proper overhaul intervals as a result (hint: 2500+ hours and 53 years is outside the intervals...). But the results were well worth the cost...

I sent mine to Aircraft Systems in Rockford, IL. Their governor overhaul guy was previously an engineer for Woodward and came recommended from others on the field. Their turn around time was excellent and their prices were as good as anyone else I called. Unfortunately, Woodward parts are getting expensive in general...
 
For what it's worth, Terry Norris at Aircraft Systems is a friend and local in our aircraft community. I use him every opportunity for Mags, Generators, Fuel Pumps, Carbs, and Prop Governers. His work has been perfect.
 
thanks everyone.

the engine is actually an O-470 that's was taken from a Skylane towplane I flew for years and now on a -2. Always was a bullet-proof engine with no issues but running it up the other day the RPM started misbehaving. I went back through the logs and it looks like this puppy has over 2K hours! It's on it's way for reincarnation now :)
 
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