Thorp Air Command - T18.net

I know a lot has been discussed about oil on the belly before and this is a report on my A/C with my new Aero Sport Power engine with the Slime Fighter oil separator I installed on the engine. After almost 70 hours on the A/C I have no oil on the belly. The Slime Fighter was installed on the crank case vent and ran down the firewall via a 3003 alum. tube to just above left exhaust pipe.

It was not a cheap separator from Spruce, but it is SMALL, lightweight and easy to install. I had bought one of the ACS oil separators, but it was the size of a small coffee can ! Sent it back ! All the other separators were about the same size (air wolf, etc). The Slime requires no additional drain lines back to the engine. Maybe just dumb luck, but it seems to work for this knuklehead You can see the small "silver" unit just above the SCATT tubing for the damper valve for the oil cooler.

Grease Monkey

RB

The Cozy Girrrls gave a seminar on their low vacuum/ saran wrap vacuum bagging method at a Flyin last summer. it's listed on the left column, LoVac. It was kind of neat to make light parts with minimum epoxy resin. The low pressure vacuum pump is hard to find and about $50+.
They have quite a list of parts available. One was the air/oil seperator second pic down. Sam Hoskins had one and said it worked good. They were quite proud it for reducing oil consumption.

Bob MO

http://cozygirrrl.com/menupage.htm

You get some good and some bad with an oil separator.
The oily vapors you don't want on the outside of your plane, maybe you don't want back inside your engine either.
The separator unit needs to be opened and inspected periodically. It will be clean initially. Even with years and lots of flight hours, but one day, after you have stopped checking it, when the ring seal deteriorates, the blowby will increase, and it will include carbon particles, moisture and acids that you would prefer to not condense and drain back into the engine.
On the other hand, if you DO continue to inspect the separator, and notice the compression get lower during the condition inspection, along with the appearance of crud in the separator, it will make sense.
Or you could do like the T-18 I looked at last week. The crankcase vent was directed down the left gear leg, and vented away from the airframe. It also had a safety vent in the cowl in case of mud/ice in the vet tube.
Air oil separators add weight to your plane.
Rich, the neat one you show is the smallest and lightest (looking) one I've seen. It looks like it drains back thru the vent tube after the engine is shut down? I don't see a separate drain tube.

It weighs only a few ounces and has an internal baffle system. It is vented down and over the left exhaust pipe. It does not have a drain line back to the engine. I did sway with the HEAVY rubber hose that some folks use to vent down the gear leg. It does have 2 short pieces of PCV rubber hose to connect the separator to the engine and the 3003 thin wall (very light eight) tubing I used to route to the exhaust pipe. I got the tubing from MSC direct and it came in a 10ft length.

I keep the oil temp right around 190-200 by using my inline baffle valve that allows me to control the amount of air from the left rear engine baffle to the oil cooler. I have a push/pull control in the cockpit to modulate the valve.

RB

I have the Andair air oil separator. Not cheap, but very well made. Does not return oil to crankcase but captures it in a small removable cup. No more oil on plane!

I too looked at the Andair separator as I have the Andair fuel valve. Both very well made. As with most of the other separators (including the Andair) they require some sort of return line, catch cup for the spent oil (MT and clean) or removing a "Brillo" type pad from the separator to clean. The Slime Fighter is as simple as it can be, nothing to MT or "clean." Howerever I plan to remove the unit at each annual and "soak" the unit in solvent...it does not specify any type of maintenance, but being the cool type guy I am, I'll just soak it for fun !

RB