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Any thoughts about this oil-leak?

ao.frog

Well Known Member
I have an Extreem IO-360 with roller lifters and a CS M/T prop, 8,5 compression.
Oilpressure typically 75-85 PSI.

Last week I found some oil along the oilsump edge and on the floor below the exhaust pipes.
I also saw some oilspray in the bottom of the lower cowl.
It all was approx equal to about half a coffeecup.

I could not see any unusual oilconsumption on the stick, nor had the oilpress been non-normal.

It was also some oilspray on the bottom of the engine, but it was not evident where it came from.
I looked specially around the front of the engine and around the prop and CS-line, but found no oil there.

I found the oil refill tube slightly loose in it's safetywiring, so I tightned it and rewired it.

I also found that about 75% of the screws holding the oilsump to the engine could be tightened beetween a half and a 3/4 turn, and so I did.
The I cleaned up all the oildrops and spray that I saw.

After a testflight, there still was some oil along the sump-edge and some oildrops and spray on the bottom of the lower cowl.
As before, it looked like it was centered below the right hand side of the engine.

On Thursday, I'll once again will remove the cowls and look for signs where the oil leak is coming from.

Does any of you have any thoughs of where to look for the leak?
Or do you experts out there need moro info before giving me a suggestion?

Thanks!
 
You find any on the starter or alternator? Might be a main seal leak. That pattern (with a conventional cowling & baffling arrgt) will end up coating the sump fwd section, starter, alternator, filter air box/throttle body. Just an idea.
 
Finding an oil leak...

Alf,

There is really no way to tell where the leak is coming from by the oil leak pattern or where you find the residual oil. Here's how I find my oil leaks, and I've had good success using this method.

First, clean the engine and cowl extremely well with solvent or whatever. Do not put the cowl back on. Go and run the engine on the ground. Any oil? If so, then you know you can find the leak by simply running the engine on the ground. No oil after ground run? This might indicate that you have a prop or governor or prop oil line leak. Reason? The prop governor doesn't really start to meter out any serious oil pressure until the prop gets into the flight mode where you need serious oil pressure to counteract CTM (centrifugal turning moment), etc.

Get yourself a can of Magnaflux developer. This is a white powdery spray that looks almost like paint. It will reveal the oil tracks or spatter from the leak. If you suspect a ground-only leak, just clean everything up, spray it around the engine and go do a ground run. The source of the leak will soon become apparent.

If you suspect an in-flight leak, clean everything up, spray on the developer, put the cowl on, and go fly. This is a little tougher because of the extra step, but the leak will show up in the developer. I recently had a leak from around the base of the 90-degree fitting in the nose of the engine where the prop governor line attaches. I was getting oil everywhere but there, until I applied the developer and went flying. Then it showed its ugly head. It would not leak on the ground, only in the air.

Other people have used baby powder and other products but the developer works the best.

Hope this helps you!
 
Could be anything!

Maybe you already have, but check the oil return lines and pushrod seals...rocker box covers too, while you're at it.

Good luck!
Mark
 
If you have any oil at the front of the engine and at the split along the bottom you have the classic front seal leak.
 
Good idea...

Hi guys.

Thanks alot for the inputs and that powder sure was a brilliant idea!

I have never heard of the Magnaflux Developer before, but I'll check if I can find it here in Norway.
If not, I'll go for the babypowder sollution.

This Thursday is going to be an interesting one.... :)
 
Where oil is found doesn't seem to relate much to where it comes from under the cowl...

Do you have a quick drain fitting? If so, find a way to be sure it is not the cause. They will spit sometimes if you don't rotate them a little upon closure.

Do you have covers over the mag(s) holes, as in the type used by Lightspeed direct crank pickup? The instructions say to not use gaskets, just sealant. They need gaskets and sealant.

I could not get the dipstick to seal without sealant on its gasket also.

UV dye is another method.
 
.

Hi again.

To answer the questions:

Yes, I have a quickdrain and will check it for leaks for sure.

I have dual P-mags and they are mounted with a thin gasket only. I'll check that too.

I'll also take a really close look at the dipstick to make sure it seals good.

Thanks guys!
 
RE:? oil Leak

Hi again.

To answer the questions:

Yes, I have a quickdrain and will check it for leaks for sure.

I have dual P-mags and they are mounted with a thin gasket only. I'll check that too.

I'll also take a really close look at the dipstick to make sure it seals good.

Thanks guys!

Hi Alf

Did you find your problem and if so........

Frank @ 1L8 ...RV7A... Flying
 
I vote for the rocker covers

Replace those cork gaskets with silicone ones..its only a matter of time before they leak.

It was almost impossible to find the cause of the leak, but I suspected the rockers, changed the gaskets and it went away.

Frank
 
Hi Alf,
I had an oil leak where the dipstick housing screws into the crankcase. Oil could be found from the front to the rear of the engine and also on the bottom cowl. I think the problem is that the dip stick housing can work loose against the lock-wire over time when checking the oil.
I originally used a teflon paste type sealer on the threads but it tends to set hard over time and it lost it's ability to seal once the dipstick housing started to move. I have stopped the leak and now have a clean engine by reinstalling and lock-wiring and using Fuel Lube to seal the threads. I figure that Fuel Lube is better as it does not set and should still seal even if the housing rotates slightly.
I also now take care not to over tighten the dip stick when checking the oil as this is what caused the housing to loosen in the first place.

Fin
9A

PS. Got your email. Looking forward to hopefully meeting you and your RV in Norway next month!
 
I've had several small leaks too

and have found that tite seal, Spruce pn TITESEAL MED WEIGHT # T25-66 works really well. It's easy to apply, never hardens, and seems little affected by FWF temps. It is the only thing that has worked for me to seal the dip stick housing gasket, and I've used it several other places with good success... I used to use fuel lube, but this seems to work even better...



See this link. http://www.aircraftspruce.com/search/search.php

Get the heavier (more viscous) version...

Good Luck
 
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