Oil leak help

jwilbur · #1 08-13-2018, 01:48 PM

It looks like there is an oil leak coming from under the lower hold-down clamp of my right mag (slick). Looks like the oil is seeping through the stud and out from under the hold-down nut. I recently changed oil and adjusted the timing of the right mag. I have not flown since then. After finding the leak on the floor - many drips worth over the course of several days, I cleaned it up, hoping it was just some drips from the recent oil change. Days later the tiny puddle is back. I torqued to 17 ft-lbs after adjusting the timing according to the lycoming manual. Yesterday, I loosened the nut, cleaned up the oil seeps again and re-torqued it. Haven't checked it yet today.

Does it make sense that oil would seep from this spot? I read on the Google that there has been some issues in the past with torque on these hold-down nuts and cracking somewhere. Any suggestions or thoughts?

Sue · #2 08-13-2018, 02:01 PM

Sounds dumb, but if you moved the mag
To retime. Could it be the mag gasket now
Leaking?

jwilbur · #3 08-13-2018, 02:06 PM

Quote:

Originally Posted by Sue

Sounds dumb, but if you moved the mag
To retime. Could it be the mag gasket now
Leaking?

It didn't look like it was coming from there but who knows. I'll check. Where the oil was gathering, preparing to drip, was where I described. Other areas seemed dry. But I'm still going to check all around the gasket. That would make more sense as far as I understand things.

BillL · #4 08-13-2018, 04:33 PM

Quote:

Originally Posted by jwilbur

It didn't look like it was coming from there but who knows. I'll check. Where the oil was gathering, preparing to drip, was where I described. Other areas seemed dry. But I'm still going to check all around the gasket. That would make more sense as far as I understand things.

Usually oil goes down, and chasing sometimes means repair non leaking areas

. A seasoned A&P helped me with the guidance of starting at the top and working down sealing possible leaks. I had to seal 6 (I think) on my engine. Patience and repeated cleaning and inspection finally paid off.

Reusing gaskets did not work well for me (this time). Once a component was removed, it turned out that the probably of a leak was increased, even though my engine was new. Mags were one of those gaskets

.

ReidVaitor · #5 08-13-2018, 05:32 PM

I had a similar leak on my left MAG, same symptoms you have. I was coming up on 500hrs so I took the MAG(s) off and did a IRAN, basically all the plastic parts replaced. I retimed; used NEW gasket, and the leaks are gone.
Not fun taking the MAGS off for 2 gaskets but my plane is the better for it since I did the work.

lr172 · #6 08-13-2018, 11:34 PM

The mag gasket will stick to the mag and case from heat and pressure over time. When you moved the mag to adjust timing, the gasket broke free, but they don't usually do so cleanly and then they leak.

Try replacing the mag gasket and re-time.

Larry

krw5927 · #7 08-14-2018, 07:21 AM

Same issue, same fix as the others. Removed the mag, cleaned mating surfaces, reinstalled with a new gasket and re-timed. Oil drip gone.

jwilbur · #8 08-14-2018, 05:16 PM

Thanks everybody. Took off the mag. The gasket was torn. Appreciate all the help

And thanks to the guys from WhiteHawk Aviation (CJR) for shooling me on how to put a mag back on properly.

skylor · #9 08-14-2018, 06:16 PM

Quote:

Originally Posted by lr172

The mag gasket will stick to the mag and case from heat and pressure over time. When you moved the mag to adjust timing, the gasket broke free, but they don't usually do so cleanly and then they leak.

Try replacing the mag gasket and re-time.

Larry

A light coating of Titeseal on the gasket keeps them from sticking so they won't tear when you adjust the timing.

Skylor

lr172 · #10 08-15-2018, 11:12 AM

Quote:

Originally Posted by skylor

A light coating of Titeseal on the gasket keeps them from sticking so they won't tear when you adjust the timing.

Skylor

Good advice here. I did similar, but used permatex #2 on one side of the gasket and an anaerobic on the other side. I assumed most don't do this and hence the explanation for the OP. All that said, I had light leakage and now use a new gasket with anaerobic sealant each time I adjust timing. In my opinion. there is not even pressure on the gasket around the circumference and therefore the naked gaskets tendency to bond to the aluminum creates an advantage as the gasket shrinks and hardens over time.

Larry