Oil leak

[romair]

I was hoping you guys can help me with an oil leak. I'm a fairly new pilot and this Mooney is my first plane. 1989 J, 1759 hours on the original engine since new. Looks like for the past 8 years it was barely flown. Initially there were some oil leaks on the floor and my mechanic helped me change the gaskets on the cylinder head covers and that seemed to have taken care of the problem. There was still some oil on the floor but it was always on the left side, right by the oil breather line, so I don't think that was something to worry about.

Yesterday I went to the hanger and noticed a few more leaks, but this time they were under the front gear doors, and on the gear doors themselves. Mechanic looked at it, thought it could be due to spreading of oil from the breather line while flying and said to keep an eye on it. Took it up today, and when I landed there was definitely more oil on the gear doors as well as some on the front tire. There was just a bit seeping from one spot on top of the cowling, so I decided to take it off. There was definitely some oil splattered on the firewall, as well as some oil on top of the magneto box, and under it. The only thing that we changed recently was the vacuum pump, but that seems to work just fine. I'm attaching some pictures. Any ideas? No noticible change in oil pressure during the flight today

Thanks

Stefan

1989 M20J

.

[Nathan Peterson]

You said that you changed the vacuum pump... Like Jim said in reference to the vacum pump.... the Garlock seal would be the area that I would be looking at very carefully.. if it wasn't seat correctly..... just my thoughts. I would clean the engine very very well and run it.... and check it every 5 min until you see something in that area.

Nate

[jetdriven]

Check the oil drainback tubes under the cylinders. Ours leaked like that at purchase and those short sections of rubber hose get old and leak. Cheap fix. Section 3 in your PC-406-1 parts catalog. -->

One more thing, that quick drain fitting that threads into that blue elbow should be safety wired to the elbow, and that oil filter should be safety wired to the accessory case near the filter gasket, not the vacuum pump.

[TonyPynes]

As someone who has chased oil leaks...although in an M20F....here are the areas we investigated:

Prop seal...replaced without success....and even the new ones can be installed incorrectly and leak still.

Crankshaft seal

Oil filler loose

Crankcase gasket or bead in front lower area where crankcase comes together.

A few different fittings and connectors.

I spent many hours with a borescope hooked to a laptop monitor and exploring the crevices....helped to rule some things out.

Had to take off cowlings, clean engine very good, run engine different RPMs, mechanic used some powder to help see leaks.

Mine was a crankcase seal between the halves lower front area that would only leak at high RPM.

[Gone]

I had one like that once that was a leak caused by a worn out O-ring on the oil drain valve

Sent from my iPad

[mooney2201]

you need to wash down your engine,make it totally oil free,fly for 15 minutes,come back remove cowling,and than look for the leak,you have so much oil i wouldnt know where to start,,oil leaks are easy to spot,just remember where you see oil,look in front of the leak,the air will blow it backwards,,,,but you must degrease the engine first,,,good luck

[davbert]

I replaced my oil cooler due to a leak when hot. Other leaks were caused by the pushrod tube seals. Do you have a marked increase in oil consumption?

[OR75]

A list of oil leak places:

- rocker covers (easy fix, those cork seals tend to age and need to be changed once a while and the screws tightened regularly)

- oil return lines clamps as mentioned by jetdriven. there are 8 of them. some are a pain to get reach.

- bolt covering the oil screen. it is a pain to get to !! it still amazes me if and how mechanics can safety wire that bolt !

- there is a fitting at the bottom of the crankcase linked to a B-nut. both can get loose. you will find it in the recess in the back of the exhaust shroud. it seems to be a vent of the crankcase. this one is tough to adjust as if you try to tighten the fitting , you start touching the shroud and out of the recess. Any input on this one is appreciated.

- filling to 8 qts and long full power climbs tend to dirty the nose gear doors too. but the pictures above show way too much oil leak for this to be the reason.

[romair]

Its time for the magnetos to be sent for an IRAN. I will pull those out Wednesday. Will also take that opportunity to look at the newly installed vacuum pump see if that's the culprit. Oil change is due as well, so I will look/replace the O-ring at the quick drain valve. Will also replace the oil drainback tubes.Will also check out what OR75 is suggesting. I'm running the engine at 5 quarts so its not due to overfilling it. Also did not see marked change in consumption, but this just started. Trying to fix easy things first before having to spend lots of money and mechanic time...

Stefan

[jetdriven]

A list of oil leak places:

- rocker covers (easy fix, those cork seals tend to age and need to be changed once a while and the screws tightened regularly)

- oil return lines clamps as mentioned by jetdriven. there are 8 of them. some are a pain to get reach.

- bolt covering the oil screen. it is a pain to get to !! it still amazes me if and how mechanics can safety wire that bolt !

**If you sit under the engine and reach it from behind the muffler its actually not hard. it only takes 30 mins to safety it there.

- there is a fitting at the bottom of the crankcase linked to a B-nut. both can get loose. you will find it in the recess in the back of the exhaust shroud. it seems to be a vent of the crankcase. this one is tough to adjust as if you try to tighten the fitting , you start touching the shroud and out of the recess. Any input on this one is appreciated.

**Thats the sniffle valve. It is a check valve in the intake plenum. It allows excess fuel to drip out if it puddles in the intake. A leaky one will allow popping and loping at idle as it is a vacuum leak.

- filling to 8 qts and long full power climbs tend to dirty the nose gear doors too. but the pictures above show way too much oil leak for this to be the reason.

**I fail to see how overfilling gets oil on the nose doors. All oil should exit via the breather hose. Anything else is a leak.

[Skybrd]

My J model had a leak that was hard to find. It was from leaking oil cooler lines. When removed, it appeared they were original from 1977. New oil cooler lines stopped most of the leaks. Another place that used to leak from the drain tubes under the cylinders.

[OR75]

- bolt covering the oil screen. it is a pain to get to !! it still amazes me if and how mechanics can safety wire that bolt !

**If you sit under the engine and reach it from behind the muffler its actually not hard. it only takes 30 mins to safety it there.

i need to check that out next time the lower cowl is off. the nose tire does not come on the way ?

what kind of wrench do you use ? i know its a 7/8.

[jetdriven]

Use a stubby 7/8" open end wrench. Move slightly, then flip wrench and move slightly again. Also, must use a new crush washer AN900-16 , split goes to case. Hand tight then 135 degrees.

[romair]

I think I found the reason for the oil leak. The "oh crap" exclamation by the mechanic sums it up.

http://youtu.be/Tu49aOhfhNA

100%

[carusoam]

Nice catch!!!

-a-

[jetdriven]

Great catch! Now is a good time to replace those magneto hold-down clamps with the improved ones.

[KSMooniac]

Wow! Late to this thread and I'm so glad you found that before it killed you! Jim and Byron are right.... Every time the cowl is off you should check that mag for exactly that problem, and especially if you leak oil all of the sudden.

[KSMooniac]

I think my current one is blue, but I can't remember now! And I just changed the oil a little while ago. My old one was blue. The one on my new salvage engine is black. I wonder if the blue ones might've been D2000 variants?

[fantom]

Mine is black....and tight

Scott.....details on the salvage plane, and your plans for it please.

[KSMooniac]

My salvage J was delivered to my hangar on Sunday. Near-term plans are to sell most avionics and instruments since those are relatively easy and I only want the engine monitor. I plan to modify my Mooney dolly a bit to securely fasten to the steel cage since I now know where those points are, and then move it to my garage for further dismantling...hopefully by Thanksgiving. Then I'll gut the wing of everything potentially useful and dispose of the carcass, which might go to the scrap yard, or someone/some shop if a good spar is useful, or I might cut it up into a nice desk for the hangar. My plane is currently in another hangar so I'm motivated to get the big pieces out and my plane back in there.

For those that might be interested, I plan for now to keep switches, circuit breakers, actuators, pumps, etc. for spares. I plan to scavenge the center console and engine controls (will need to be repaired) to replace my throttle quadrant and console. I also will (eventually) retrofit the overhead ventilation system to delete my pop-up cooling scoop that doesn't work very well. I'll also rebuild the seats from the salvage plane (especially the individual rear buckets) and upgrade my plane, then sell my seats that are still in great shape. I'm keeping all of the firewall-forward stuff as well to start assembling a replacement engine.

So, for the scroungers... I'll sell just about everything else! Available now are an entire empennage (not ready to split it up yet), KFC-200 autopilot system, normal instruments, WX-10 stormscope system, seat belts, interior panels and carpet (pretty nice, but I need to clean them first). Today I dropped a KMA-24, KX-165, and KT-76A off at my avionics shop for bench-checking and IRAN. There is a nice GNS-430W that I already have some interest in, but it isn't sold quite yet. I plan to send the KI-256 and KI-525 gyros to Bob Bramble for bench checking and IRAN too pretty soon. The nice yokes and shafts are spoken-for as well, but not yet sold.

I'll start a new thread soon to act as a rolling inventory/ad page, but I'll welcome inquires via PM for now.

[fantom]

My salvage J was delivered to my hangar on Sunday. Near-term plans are to sell most avionics and instruments since those are relatively easy and I only want the engine monitor. I plan to modify my Mooney dolly a bit to securely fasten to the steel cage since I now know where those points are, and then move it to my garage for further dismantling...hopefully by Thanksgiving. .......I'll start a new thread soon to act as a rolling inventory/ad page, but I'll welcome inquires via PM for now.

Very cool project. Is that Thanksgiving this year?

Best of luck with your efforts, and I trust the new thread will be a pictorial history of the project as well.

[KSMooniac]

Yes! Unfortunately my detached garage renovations were a bit delayed and conflict with this project, which of course appeared when it did, not necessarily on my schedule. I need to build at least one workbench/cabinet assembly at the garage next, and that will be good enough to bring the fuselage home to work on it more conveniently. I *think* I can get that far by Thanksgiving, then dive into the wing and get it gutted and moved before the end of the year so I can get my plane back in her hangar. We'll see...

[romair]

Hey Byron

You mentioned that the quick drain fitting that threads into the blue elbow should be safety wired to the elbow. Could you snap a picture of that when you get a chance so I can visualize what I need to do?

Thanks

Stefan

[romair]

Not to make anybody more paranoid about this single point of failure in our planes, but to the left is the old clamp that was on the magneto when it started being loose, and on the right is a brand new one. Yes, they are the same. I initially thought that I had the old style clamps and therefore that's why the securing mechanism failed. But it appears that I had the new style ones...to add insult to injury the plane was in annual 30 hours ago - Don Maxwell. I guess I will be removing the cowling more frequently from now on and give a good push to the magneto.

Stefan

1989 M20J

[jetdriven]

Wow, that is interesting news. That clamp has been redesigned three times and if it left Don's shop I'd bet my life that it was tight. They know what they are doing. So, it appears that the problem is not totally fixed. I suppose for now the only option is to replace both star washers at annual and mark the nuts with torque-seal. Check that the mag can be held tight with only one clamp tight, and check both clamps that way. Then pull the top cowl at a minimum of 25 hour intervals and give everything a good tug.

Stefan I wll get you a pic of that safety wire. At the end of the blue drain fitting (where it threads on the elbow) there is a small hole. You run safety wire though that, around the elbow. It keeps it from unthreading from the elbow that way.