Stewartb that sounds just like what I am headed for. My AI owns part of a flight school and commonly field overhauls their engines. He is fine with me doing the work and him inspecting as we proceed. Would you be willing to share what the overhaul cost you, round numbers are fine, just trying to assess how big a cliff I am jumping off. Will 20k do it including new nickel cylinders and cam if crank is ok?thanks
Low oil pressure, overhaul time?
- Thread starter Riley
- Start date
behindpropellers
Registered User
NE Ohio
20K should work. I put a new top end on last year for about $6k.
Steve Pierce
BENEFACTOR
Graham, TX
You can spend $10-12 K with you doing all the work. Check the availability of new cams as well. last timeI needed one there was a problem in the supply because the same manufacturer makes them for all the big names. Also if you go to a one piece cam (new) it will cost you to modify the accessory case. Your cam can probably be re-certified. I had an 800 hr since new engine with a bad cam and Ken at LyCon told me he was seeing more problems with new ones.
NimpoCub
Registered User
Nimpo Lake, BC . . . AKA "the Floatplane Capital o
Bart has done something over 1500 engines & loves to "massage" 'em to extract that extra HP.
You won't meet a nicer, more knowledgeable guy. He s'pecially loves Cub folks.
Call 1 800 264 6019 & ask Bart some questions... like "Where should I send my $$"
You'll be glad you did!
Factoid: My "massaged" 0320 beats the neighbor's 0360 off the water. Mine is 170hp, his is 180, with a big weight penalty.
Point is, DO IT & be happy. Patching is just prolonging the agony.
You won't meet a nicer, more knowledgeable guy. He s'pecially loves Cub folks.
Call 1 800 264 6019 & ask Bart some questions... like "Where should I send my $$"
You'll be glad you did!
Factoid: My "massaged" 0320 beats the neighbor's 0360 off the water. Mine is 170hp, his is 180, with a big weight penalty.
Point is, DO IT & be happy. Patching is just prolonging the agony.
S
StewartB
In rough numbers my honest engine overhaul cost was between $12-13K. As with the rest of the project I was good at keeping close track in the beginning and better at living in denial toward the end, but the engine overhaul was not one of my budget busters. To Steve Pierce's cam comment, my new cam was manufactured by ASI (Air Support Intl) but purchased through Aircraft Specialties. In my case the old cam was in surprisingly bad shape. In fact that's what drove my decision to overhaul a 1200 hour engine. My intention had been to pull two cylinders to address valves/low compression. That the cam was toast was undeniable after pulling the first cylinder and taking a peek. I'll be curious to hear what your original cam looks like.
Stewart
Last edited:
Much thanks to all for the advice, will talk to Bart and aircraft specialties, I will assess cam when I see it but I am assuming new is likely required. I will do my best to document my overhaul adventure but I fear documentation is not my strong suit.
I have no reason to doubt the integrity of the engine mount, but should I have it rebuilt at the same time?
I have no reason to doubt the integrity of the engine mount, but should I have it rebuilt at the same time?
The engine is off and on stand. Cylinders, accessory case and oil pan are off. I am ready to split case but am waiting for IA to have time to assist as I am a virgin as far as getting this deep into the engine. As Stewart said all is going fairly straightforward and I am confident of a positive outcome. As far as I can see the cam is clean and corrosion free but should be easier to check when out of case.
In regards to your engine mount, I'd just look at it very closely and pay particular attention to the spots where all the tubes are welded together. If you see anything that looks like a crack, get out the magnifying glass, or go one step further and do a dye penetrent inspection.
What shape were your cylinders in when removed....any stuck rings? How about the oil pump gears, are they ok?
Keep us posted.....
What shape were your cylinders in when removed....any stuck rings? How about the oil pump gears, are they ok?
Keep us posted.....
aviationinfo
Registered User
Southwest WA
I'll second that, am real interested in what caused the oily plugs.
how did the rings feel...I just pulled a 470 cylinders off on two for low compression....older engine had high oil temps....the cylinders were perfectly sized and flawless....the rings on those two had a very rounded off feeling. the edges were not squared and sharp....That owner was very happy we investigated rather than replace
Update mechanic is very busy reassembling a school plane so no "professional opinion" but rings are not sharp edged and bore of cylinders are glass smooth with no crosshatch evident, which may explain oily plugs. accessory case behind oil pump gears scored which may allow some bypass thus low oil pressure. IA says engine probably have made the 200 hrs to tbo without failure, and is chiding me somewhat forspending money before necessary. I can only respond that this is not my "business" airplane and I am enjoying the process, Besides cleaning plugs every second flight was becoming a pita. Cases are going to Divco and steel parts to Rick Roman as per the IA's direction, any thoughts on good shops for OIL COOLER , CARBURETOR, and BENDIX MAGS ?
UPDATE ADDITION: Camshaft had started to break through nitriding at shared lobes, tappet bodies showed effects of nitride breakthrough also at shared lobes, camshaft is probably rebuildable, however IA suggests and I concur that everything short of crankshaft (which along with bearings show minimal wear) and rods should be replaced with new inside cases. IA suggests that if cylinders are round and near spec some savings could be achieved via in shop overhaul of existing. I have significant confidence in IA however I am interested in opinions as I have received some great input here.
njneer
Registered User
Chugiak, Alaska
I had similar symptoms with my engine at 1,100 hours. Long story short, the first ring on the forward, right cyclinder fell out in 7 pieces, cam was hosed, oil pump gears and housing badly scored. One word of caution for the re-build, the repair manual instructs the mechanic to place the gasket for a prop governor under the blind plate on the high pressure oil port on the back of the engine. There is a tiny footnote that can go unnoticed which says to substitute a solid gasket under the blind plate if you don't have a prop governor. Don't make the mistake of using the weaker gasket under the blind plate. Mine blew out at about 10 hours after the rebuild dumping 8 quarts of oil in about a minute. Fortunately, I was at 13,000 feet when it blew out and I was able to dead-stick 18 miles to a gravel strip. If you don't like flights that finish with dead-sticking, make sure you get the correct gasket there. Send me a message if you want more details.
