Jump to content

M20K 252 Oil Consumption


MooneyMark

Recommended Posts

Although I'm not at all sure, I take it my tech checked proper fitment of the checkvalves. I pointed them in that direction and he also mailed with Mooney concerning this matter, and he said they're okay and fitted correctly. I would just love to pop of the cowling and check it all myself, but I've decided to leave it to the pro's. I am wondering how 'pro' he is though, cuz he billed me one hour labor for swapping the landinglight... This I will do myself next time. 
So assuming the checkvalves are okay and the crankcase pressure is high, but within limits (they check this with an old ASI... never knew!) then that leaves the valvestem seals. Need to check if they did the boroscope.

Mark,
I like what you are thinking. Maybe it’s time to become the pro. Pop that cowl and see what you have. Your life depends on it. Just saying...

Aron

A&P, IA



Sent from my iPhone using Tapatalk
Link to comment
Share on other sites

  • 3 weeks later...

Well, they checked the barrels and there is no excessive oil, and the exhaust before the turbo is clean. So the oil is added to the exhaust at the turbo. The checkvalves have been fitted correctly I am assured. They know about the specifics concerning their fitment and they have been leak tested overnight, so the valves are good, and fitted correctly. I've sent an e-mail to mr. Mike Busch by the way, but never got a reply.

Next thing on the list is checking the scavenge pump...

If the the pump is okay, maybe then it's time to take of the turbo for a rebuild?

Link to comment
Share on other sites

Dan-  I had my turbo replaced about a thousand hours ago (231).  The inside of the exhaust has always been completely dry.  I don't honestly stick my finger in the exhaust every time I pre-flight because of the mess, but I do it often.  I do open the turbo door and inspect the turbo and the clamps every flight, and I look for signs of oil.  No oil is normal, oil is not normal.

Link to comment
Share on other sites

13 minutes ago, MIm20c said:

If you do send the turbo out I’d recommend Main Turbo in CA. Talked with them on the phone a couple times and they seem like straight shooters. 

Ha, those are the same people my tech is dealing with at the moment. Good to know, thanks!

Link to comment
Share on other sites

Mark,

if the scavenge pump is good I would put new check valves in its way cheaper then the turbo.  There is one more thing to check. The hose from the turbo drain to the return check valve up to the scavange pump. You can have a internal flap of the rubber restrict flow in one direction. Long shot but worth checking. Good luck 

Link to comment
Share on other sites

Just had call from the mechanic, the scavenge pump is good, as a matter of fact it is part (apparently...) of the starter assembly that was changed out for a new one early this year. The checkvalves are only two years old and have been tested. I'll have a chat later about the return hose, thanks! I was thinking if the scavenge pump is good, then maybe it gets too much oil for the pump too handle. Although the capacity of the scavenge pump should be 140% of the volume of oil being delivered. Can the flow of oil in to the turbo be regulated? It should be 3 qrts in and 4 qrts out,

Link to comment
Share on other sites

After landing I let the engine idle for a few minutes to let the turbo cool, the mech suggested, since the turbo and ancillaries appear to check out fine, to let the engine run at 1400/1500 rpm for 30 secs before idle cut off. This allows for the scavenge pump to do its work better. Any thoughts?

Link to comment
Share on other sites

  • 1 month later...

It appears to help to let the engine idle at around 1.400 revs a little while before shut-down. The last starts I had a clean gear door, but I'm not counting my chickens yet.

Now waiting for the days to lengthen a little bit more so I can pick up my IR training again!

Link to comment
Share on other sites

  • 4 months later...

The e-mail my mechanic sent to Mooney and all other parties involved sorting my engine out. Maybe it can be of use for anyone else, so just putting it out there. Mind you, they checked the cilinders for oilleakage with an endoscope and had no reason to suspect the valvestem seals.

”Hi Guys,

 

For a number of years we've been trying to solve the mystery of the oil coming from the exhaust tailpipe of a Mooney M20K with a TSIO360MB engine. (factory new 1989, 1168 TT, no major repairs been done to it apart from 1 cylinder change 2 years ago)

Every time the aircraft was started up or flown the RH nose landing gear door and belly where wet of oil coming out of the tailpipe.

At some point the turbocharger was changed. There was always about a cup of oil standing in the turbine housing. This didn't cure the problem.

The one way valves in the oil system to/from the turbo where cleaned several times and eventually changed for new ones..... unfortunately no joy.

We've checked the scavenge pump but it seemed OK. At some point the the starter clutch was broken and the complete housing was changed including the scavenge pump. We hoped that this would fix it..... No....

 

During a 100 hrs inspection some metal spring particles where found in the oil filter. Small bits like a lipseal spring. This gave me the idea to have a look at the intake valve guide seals since they have this kind of spring installed on the seals. I removed the valve springs and found 5 out of 6 seals being damaged. On 3 of them the springs where completely gone and on 2 others the seal was partially broken but the spring still in place. The only good seal was installed on a cylinder which I changed about 2 years ago. I guess that the one on the old cylinder was damaged too.

 

I changed all 6 valve guide seals. Ran the engine and no more oil from the exhaust tail pipe. The aircraft has made several flights/starts since and so far good news.

 

I thought this can be helpful to share.

 

Greetings, Martijn”

 

 

klepsteel 1.jpeg

klepsteel 2.jpeg

klepsteel 3.jpeg

Edited by MooneyMark
Pic was added
  • Like 8
Link to comment
Share on other sites

This is the little spring we found in the oilfilter. I suspect this debris could also be to blame for the failure of the automatic wastegate, it is a hydraulicaly operated system.

 

veertje.jpeg

Edited by MooneyMark
Pic was added
  • Like 1
Link to comment
Share on other sites

8 hours ago, carusoam said:

 

Fantastic closure, MooneyMark!

Got any pics or info related to the valve seals?

How is the IR Training going?  Plenty of sunshine this time of year... I really liked Amsterdam in the summers.  :)

 

Training has been slow the past six weeks, I did some practice runs to EHGG but this weekend I’ll be back at the flightschool.

My dad passed away exactly one week ago, we operated the Mooney together and maintenance was completed just in time to do a very emotiononal farewel pass at his funeralservice.

We both loved flying and we loved flying the Mooney together. He followed progress on maintenance right up to his passing and was thrilled to hear they finaly found a ‘smoking gun’ and the cause for the misterious oil consumption. I was in tears because at that time my dad was in the ICU fighting for his life and the doctors were still trying to figure out what was killing him. I said ‘dad, they fixed the Mooney, they will fix you too.’  Regretfully it wasn’t meant to be, he would have loved to take her up once more.

Image-1.png

Edited by MooneyMark
Pic was added
  • Like 5
Link to comment
Share on other sites

3 hours ago, MooneyMark said:

Training has been slow the past six weeks, I did some practice runs to EHGG but this weekend I’ll be back at the flightschool.

My dad passed away exactly one week ago, we operated the Mooney together and maintenance was completed just in time to do a very emotiononal farewel pass at his funeralservice.

We both loved flying and we loved flying the Mooney together. He followed progress on maintenance right up to his passing and was thrilled to hear they finaly found a ‘smoking gun’ and the cause for the misterious oil consumption. I was in tears because at that time my dad was in the ICU fighting for his life and the doctors were still trying to figure out what was killing him. I said ‘dad, they fixed the Mooney, they will fix you too.’  Regretfully it wasn’t meant to be, he would have loved to take her up once more.

Mark,

I’m very sorry to hear of your fathers passing.

Clarence

Link to comment
Share on other sites

Hi MooneyMark,

Sorry to hear about your dad.

It looks like the rocker shaft holddown nut is missing the lock tab.  Picture below

Also this is clearly the oil problem but you should have had a puddle of oil dripping from the intake drains and that would have helped with a quick diagnoses.

I would check the drain check valve above the left cowl flap and make sure the lines are clear to each intake port.

Jim

Image result for TCM TSIO-360 rocker shaft lock tab 

  • Like 1
Link to comment
Share on other sites

3 hours ago, Jim F said:

Hi MooneyMark,

Sorry to hear about your dad.

It looks like the rocker shaft holddown nut is missing the lock tab.  Picture below

Also this is clearly the oil problem but you should have had a puddle of oil dripping from the intake drains and that would have helped with a quick diagnoses.

I would check the drain check valve above the left cowl flap and make sure the lines are clear to each intake port.

Jim

Image result for TCM TSIO-360 rocker shaft lock tab 

Those won’t be needed until reassembly, note that the valve spring compressor is still hooked on the rocker shaft.

Clarence

Link to comment
Share on other sites

Great additional pic of the Dad and family!

Like you...  Our Mooney is the bridge that connects three generations.  

We Couldn’t have done it so well without a Mooney...

We have a similar pic that quietly resides behind me while I type.... :)

... an offering of peace and comfort ...

Best regards,

-a-

  • Like 2
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.