Jump to content

Recommended Posts

Posted

Hello all, I recently had my vacuum pump replaced in my 83 M20J with an overhauled Tempest pump.  After starting it up today, I noticed a large puddle of oil coming from the front nose gear door area.  I took off the top cowling and noticed oil near the vacuum pump, near where it bolts onto the engine and below it.  I checked all of the nuts on the pump and it was tight.  The A&P also put a new gasket when replacing the pump.  I checked the oil and noticed there was almost none left.  During preflight, there was 6 quarts.  Any suggestions on what it could be? Thanks.    

IMG_1005.jpg

IMG_1008.jpg

IMG_1010.jpg

  • Like 1
Posted

On the -A3B6D engine, there is an adapter for the spin on filter that is attached to the accessory case by the threaded fitting that the filter screws onto. There is a rubber gasket between the adapter and the accessory case. When changing the filter it is possible that the adapter comes loose and damages the gasket.

  • Like 4
Posted

If the oil is coming from around the vacuum pump, my guess is something is wrong with the new gasket; torn, wrong, miss-installed??

Posted

I’m not a mechanic, but if I’m not mistaken, that  tempest vacuum pump flange has a star/pointed shaped  gasket that sits in the notched grooves that are centered on each side of the flange—rather than a traditional flange gasket.  I bet there’s  an issue with that gasket either missing or misaligned.

  • Like 4
Posted
7 hours ago, dc0341 said:

Hello all, I recently had my vacuum pump replaced in my 83 M20J with an overhauled Tempest pump.  After starting it up today, I noticed a large puddle of oil coming from the front nose gear door area.  I took off the top cowling and noticed oil near the vacuum pump, near where it bolts onto the engine and below it.  I checked all of the nuts on the pump and it was tight.  The A&P also put a new gasket when replacing the pump.  I checked the oil and noticed there was almost none left.  During preflight, there was 6 quarts.  Any suggestions on what it could be? Thanks.    

IMG_1005.jpg

IMG_1008.jpg

IMG_1010.jpg

Curious.  Did it blow all the oil out the first time it was started after maintenance or did it take a few starts or taxis for this to show up?  Just learning from your experience.  I’m adding vacuum pumps to my list of things to better understand and worry about list.  Thanks.  

  • Like 2
Posted

I like the fluorescent dye to find a leak.  Clean the engine with mineral spirits.  Add 1/2 ounce or so of the dye.

Run engine at a fast idle 1200 RPM of higher for 2 minutes. Shut down, pull the cowl and use UV lamp to find leak/

  • Like 1
Posted
12 hours ago, DCarlton said:

things to better understand and worry about list.

Before I came to MooneySpace. my list of things to worry about was manageable -- now that I read this forum almost every day, I worry about almost everything. :(

  • Like 1
  • Haha 10
  • Sad 1
Posted

Fill with oil

Remove plugs

Spin engine while somebody watches it gush out

That type of loss should be easy to pin down. 

Posted

There is an oil seal at the base of the vacuum pump drive shaft.  It's not the gaskets that insure against oil leaks - it's the seal !

Clearly the seal was compromised during the pump change.

Remove the pump, pry out the oil seal (that's the difficult part) install new oil seal, gaskets and pump. 

  • 2 weeks later...
Posted

Gee, are those wide flange adel gaskets?!

So neat!! 
 

A friend of mine makes silicone components on the Boom test airplane. Their engineering spec is very tight. He showed me the molds for the engine to airframe inlet. Much like a 731 Falcon inlet install. Really neat process. You’ll have my next customers hose order. 
 

In the OP pic what’s the gold/rusty part at the filter gasket area. That looks strange to me. 
 

-Matt 
 

 

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.