M20 oil seperator

[Frank Green]

I am going to put one on my 22. I read the old threads but does or can any body have some pics of your installation you can post? Curios where they have been mounted and issues from using them.

[Gilbert Pierce]

See attached pictures of M20. My accessory case has a fuel pump pad with a block-off plate on it. I drilled and tapped that for 1/8 pipe and screwed a 45 degree barbed fitting into it for the M20 oil return line.

The M20 works but I still get a film of residue, no drops or drips on the belly. I clean it off about every 50 hours with 409 and then apply REJECTX on the belly which makes it easier to get the exhaust stain and oil film off. The amount of oil film I get is a function of how hard I run the engine. Also, where the vent line exits the cowl can effect the amount of film residue I get. If you have the vent in the sweet spot now it will be the sweet spot for the M20.

[Frank Green]

Thanks, that helps as I have the spin on also.

[smcnutt]

Here's how we mounted it. We've been pretty happy with it. As it turned out our major culprit to our oily belly turned out to be a failing wet vacuum pump but the engine vent was also a problem that the M-20 solved. We still get some stuff on the belly but it's been reduced by 90+%. What's showing up on the belly could be mostly from the exhaust rather than the vent but we've not really checked. Now we clean the belly just occasionally rather than after every flight. Saved a bunch of money from oil going overboard anyway.

[idahopacer]

I know this is an old thread but I need to know if you run both the engine and
the wet vacuum pump through one M 20 seperator and what p/n seperator is used ?

[Steve Pierce]

No, just the engine breather. The M20 I am familiar with will not handle the blow-by from a wet vacuum pump.

[51-pa22]

Frank,
Here is on old installation, cleaned up a bit.

[smcnutt]

We switched our failed wet vacuum pump out for a dry one so we just eliminated that as an issue. Our M20 is only inline with the engine breather. It sure has cleaned up the belly of our plane and reduced our oil loss. We can typically make it to an oil change with only adding 1 quart.

[wyandot jim]

The engine guys that are in the know, Mike Bush & John Deacon do not recommend the separators for the crank case breather. Why because the gunk/water and moisture just drains back into the engine. Yes I have a large one on the Bonanza for the breather and wet pump. Our Baron has the stock ones for the wet pumps. After reading what the engine pros say probably wouldn't install one. The belly of our Pacer and 7GC Champ stays clean without them and they have dry pumps that through craps every 3-4 years. Our wet pumps are original as far as I know.

[Steve Pierce]

Who is John Deacon? I am familiar with Mike Bush. It is my understanding that the water is a vapor when it comes out of the engine so it goes out the vent not back in the crankcase. A lot of my Super Cub friends run a baby bottle over the crankcase vent to keep the oil off the belly.