Investigate oil leaks!! HUGE pucker factor!!

[Jeev]

1978 M20J -

History:

Over the last 40 hours and month or so I have noticed my nose gear has been a little wet with oil after a flight with maybe one or two drips on the nose tire.  On Monday after not flying for a week I decided to take a quick flight. Preflight was good but during the run up I had a drop on both Mags of 150rpm and almost no difference between the two, it is usually 50-75rpm drop.  I did a full power run up everything was smooth and the engine monitor was showing everything was normal.  In hindsight I should have scrubbed the flight but my thinking (wrong) was that it was still in limits (175 drop) and it may be due to the weather 30DF drop that week.  Well I had a wonderful uneventful flight for 1.0....... I was lucky.

Today I was going to go up for an hour to practice approaches for my upcoming checkride....... I walked up to the aircraft and noticed that there was a decent amount of oil that had dripped down through the open nose gear door on to the nose tire.... This "leak" had been "small" but large enough to leave a in-flight trail of oil down and over the nose gear doors. I had my mechanic investigate it two weeks ago and he said there was no problem and he could not find the leak even after I showed him the oil trail.

So back to today; I was going to to another run up to see if it was fouled plugs then a flight if all was well. After noticing the increased oil I pulled to top cowl to trace the oil leak and while I was in there gave the Mag a shake..... Guess what?? It was very loose and that was where my oil leak was  I am finding another mechanic! I cant help thinking of how long I had been flying on a loose MAG. Two oil changes and some other maint and it was not seen.

After 4 months of ownership I have learned a good lesson. Any substantial change should be investigated and if I am not satisfied with the diagnosis or lack there of I need a second opinion.

So if any of you have oil dripping on your nose tire even a small amount take 10min and check the security of the Mag.....  This was the 1st time in 3 years of flying I was really freaked out! cant stop thinking of that Mag coming loose....

__________________

[flight2000]

That's one of the down falls of the cowling design in my opinion.  I got my PP license in a Piper Tomahawk and the cowling was a gull wing design that allowed you to open both sides for a full view of the engine compartment during pre-flight.  Two cam locks secured it in place.  Makes me wonder if the speed of the aircraft (slower than a C150) had anything to do with the cowling be able to have this type of design.  Good lesson learned though.

Brian

[N6843N]

Your tale is a good leason for new pilots and a great reminder for the more experience group. NEVER accept something you KNOW is not right. The excessive mag drop and the uncaring mechanic were wrong. When I worked on the ramp at AMR Combs PSP we had a Bonanza taxi in one Sunday. When I parked him I noticed oil running off of the belly. I asked him about it and his reply was "Continentals are supposed to leak". I asked if I could look under the cowl and he gave me the go ahead. The first thing that caught my eye was the vaccum pump lying unattached on the nose gear well. I pointed it out and he looked abit taken back and said he had not even noticed the lose of the vaccum instruments. A few minutes troubleshooting can sometimes prevent a lot of heart ache. 

[Jeev]

Thanks for the link Jim I googled SI 1508B and will be giving a copy to the owner of the shop that I will not be using any more so in the future the mechanic will recognize the symptom of the oil leak on Mooneys.  I will also let him know that the responsibility is partly mine for not being persistent.

Here is the link to to Service Instruction if anyone wants it:  http://www.lycoming.com/support/publications/service-instructions/pdfs/SI1508B.pdf

Have a great week!

[KLRDMD]

Quote: Jeev

I googled SI 1508B and will be giving a copy to the owner of the shop that I will not be using any more so in the future the mechanic will recognize the symptom of the oil leak on Mooneys.  

[Jeev]

Quote: KLRDMD

This wasn't the MSC at KVGT, I assume ?

[Kwixdraw]

You may want to do oil analysis next go round if you don't already. Someone posted on here that the loose mag can affect the oil supply too. I assume that is from the drive gears in the accessory case. Check the filter well too. I might even do the oil change early just 'cause I am paranoid and would like to go on living pretty much forever. At the FBO where I had my 201 based they put a Cherokee Dakota in the drink off Long Beach in exactly that way, so it isn't just Mooneys.