significant oil leaks after adding oil-air separator

[Bryan Cotton]

Copied from another thread:

I've also got another set of CB Performance oil control springs on the way. Thanks 429TB for the info.
111-115-421a Oil Relief Spring - OEM
111-115-425a Short Oil Relief Spring - OEM

~$12 shipped.

These are stock springs. I also found the largest Harbor Freight transfer punch is a snug fit in the inside of the pistons. A little tape and it's a tight fit. You can chuck it up in a 1/2" cordless drill and make sure the piston is free in the bore.

https://www.harborfreight.com/28-piece- ... -3577.html

[funflyingguy]

appreciate the info.

i used a threaded rod with electrical tape wrapped around one end. with a little emery cloth wrapped around that, not hard to smooth out the bores. each took about 15 minutes to emery cloth, making sure no metal flakes or dust remained and then did the pistons. tested each by threading the pistons onto the taped end. they fit nice and straight and tightly and slid out easily afterwards.

thanks bryan and 429TB....

[funflyingguy]

now the rest of the story.... seems my aerovee had a couple of things off a bit.
1 - the oil dipstick marking were low by about 8 ounces. changing the oil/filter allowed me to carefully fill and note the disptick level. i also received and verified with the black VW standard dipstick, which is far easier to read and right now more accurate. i may switch to it one day if a add an access panel for it in the cowling. or i'll accurately calibrate and use a new aerovee dipstick when sonex is able to ship it.
2 - crankcase was overfilled causing some of the oil leakage.
3 - the air-oil separator as it came, was causing way too much backpressure. i pretty much gutted it and drilled out the smaller air channels. but it wont go back on just yet.
4 - the oil pressure sender i got with the sonex, i could not identify the model of. it resembled the german made VDO line of senders and had 2 terminals. it was dated about 13 years ago. so it may have gone bad. i replaced it with the unit sonex stocks with 1 terminal and 80 PSI max. my MGL enigma was set to 100 PSI max for the sender i removed. i changed that to 80 PSI. after almost 3 hours of flying, it gives very reasonable readings, maxxing at about 75 PSI when the 20W50 oil is cold at about 1300 RPMs and about 58 PSI at about 160F and 3000-3100 RPMs. it drops to the mid-twenties PSI when the oil is hot at about 1000 RPMs.
5 - the original sonex dipstick was coming loose at times; now i know why. it was rubbing against the aluminum baffling in that area, with the engine vibrations gradually lifting the dipstick up allowing oil to vent. i enlarged the hole in the baffling so that the dipstick and cap have plenty of clearance. it stays in place now, but i think it is still more loose than it used to be.

with the above corrected, i no longer have any obvious oil leaks. time will tell if that holds true.....

on a different note: i cut and shaped a [lower] oil cooler cover plate out of aluminum. it completely blocks the 'smiley' opening for the oil cooler from the inside. today, with the temps around 45F to 50F and the new cover plate, the oil temp leveled off at about 180F - 185F after about 30 minutes of flying. without, it showed a max of 136F. i've cut a slightly smaller cover plate for use at higher ambient temps.

so thank you all for your support and suggestions. all good!