O-470K starts great but won't run up -RESOLVED-

[172heavy]

A friend an A&P/IA found a mouse nest in the air box/ carb in an airplane with similar problems.

[hotrod150]

Probably not the problem but don't forget to check the fuel screen at the carb inlet.

[Zzz]

People, it is a fully acknowledged fact that both practically and legally, a forum is no substitute for the eyes of a qualified A&P. We operate under that assumption here, and it's even stated in the Newbie Guide and the Terms of Use that everyone agrees to upon registration.

However, there is no reason to be sheepish about asking questions of the community to help broaden your knowledge and understanding of how aircraft engines work, and especially to get some ideas about diagnostics. Opinions will be tossed into the ring that span the spectrum of experience and competence, and they're all free. Some will be wrong. Some will be dead on. The conversation is for entertainment, and at no time should anyone be chided for using the Internet to research their problem, or discouraged from seeking knowledge on a topic that all pilots should be educated on.

Darinh owns his bird, and he can shoot it repeatedly with a 12 gauge and set fire to it if he wants. But if he's going to fly it, we should assume from his well written questions that he's a level headed owner and will seek a thorough inspection and a qualified return to airworthiness, whether he's solved the issue himself or not. A suggestion from one of you may end up being relayed to his A&P, solving the mystery, and saving darinh a lot of money in diagnostic time. Nothing wrong with reminding someone about the risks of unqualified work, but please be respectful and address others as you would if you were speaking with them in person, and let's not dwell on it.

Thanks.

[Darinh]

Well I thought I would update all who were kind enough to offer suggestions on what my problem might be. I spoke with my IA after he returned and described what was happening and first thing he said was, "Sounds just like a situation we had with a governor driving the pitch in the wrong direction."

Apparently he had had a notable engine shop overhaul an engine for a customer and the prop governor was also overhauled for a prop upgrade. As all of you know, I'm sure, Hartzell and McCauley props use oil pressure to drive the prop either coarse or fine. My prop was a McCauley but my Woodward governor was set up for a Hartzell so anything above 1200 rpm or so was just bitting way too much air and the engine couldn't spool up. Swapped the plugs on the Woodward gov. and she ran right up to 2600 static.

However, being that the plane hasn't been flown for 25+ years and know now that someone jacked with the governor leaves me a bit leary about the prop and the engine altogether. So after much thought, I have decided to pull the engine and prop for a Pponk Super Eagle conversion and a new-to-me C66. Afterall, I will by flying my family around in this plane and I want something I know is going to be reliable.

Thanks to everyone for the replies and help.

[Zzz]

I wouldn't have considered that in a million years. Thanks for updating us!

[soaringhiggy]

Well, that is a great find and I hope you have fun with all of the mods.

I would not have gone there either.

[hotrod150]

I was just about to suggest that you check the governor.

[dirtstrip]

Amazing what can be learned on an open forum. Thanks for getting back with the solution.

[182dude]

Oh you wont be sorry...just got a call from them up at pponk today! They are going to start the final assembly of my 470-50 and i cannot wait!!!

Great people to work with and very good follow up...ticked the pocketbook at roughly same cost as a fact reman, except im going with a new bigger scimitar...theyve been in touch with me about once every 2 weeks to let me know how its going, my thoughts are let the pro's handle it, no need for a call every day, but they have been very easy to deal with...can you say mom and pop service...we need more of that in this country!!

Mike

[Lizard]

Darin,

Thanks, I learned something useful today.
Enjoy your project.

Dale