Les Holman Oil breather separator

[Mark Kramer]

Bob, I gotta call him and see if I can get a small one. Will have to drill and tap some holes. Right now I have a can with scrubbie stuff in mounted on top of the engine. Will try it in the next few days. Working on installing Belite tc-4 temp gauge right now

[Bob Wood]

Mark,
I am sure he has them. You can see mine in the pic below. Probably swap out your bolt on with this reed and you are set.

I also run belite gauges. The Tach,  VSI, alt, airspeed combo,. inclinometer, and cht/egt combos. They are great.!!

Where are you located? How much do you fly?

[Mark Kramer]

Hi Bob, talked to Scott today, the vw breather is 3 inches square and will not fit on the flat spot on top of the Mosler case. I might try and make an adapter to use one, but would rather try to find one that was originally used on these engines. I would have to though, drill and tap holes, as there are none for bolts. Engine also has no dip stick hole. Weird. Anyway...got my private ticket in early 90s, recent flying was a Rans S4 Coyote taildragger. Flew it for 3 yrs , recently sold it. Anybody out there that might know where to find one of those little 2 bolt reed breathers, please let me know.
Thanks Mark

[Mark Kramer]

Oh yeah, I live in southern Maine. Too cold for winter flying here, for me that is. Nothing but trees underneath you also. A simple power failure could be bad

[Mark Kramer]

Oh hey Bob, or anybody,
A pic of the engine and the little valve from an old Mosler catalog.

[Bob Wood]

ok, too bad the case 1/2 ridge is right there if that area was smooth you could maybe bolt the 3" one from Scott right on...

[Mark Kramer]

Well, ran the engine again today with the latest rendition for crankcase venting and oil separating. Worked great, not a drop of oil came out. I used an Aluminum catch can full of that stainless steel scrubbie stuff, with an automotive Pcv valve at the top with a hose to a clear water bottle so I could monitor it for oil. I do have a plan to lower the catch can, removing some fittings. I think they would break anyway. The engine shakes more than I like, spits fuel out the overflows, and the tiny tach is all over the place. Pretty sure I have the hub balance weight where it belongs, didn’t seem to make much difference from when I ran it last. Advance the throttle and one exhaust gas temp climbs over 1200 quickly. Is it hard to tune when it shakes, or does it shake because it is out of tune? Also not sure if I’m getting a full 28 degree spread out of the Morse Fairbanks magneto. I have it set to fire during hand propping, so I won’t get bit, but not sure if it is advancing to 28 degrees back. My brain hurts.

[Mark Kramer]

Oh, forgot. Here’s a pic or two

[Mark Kramer]

Before I talk about my breather issues, let me catch you up on my carb changes. Took the new VM 26 carbs off and went back to the stock arrangement. Drop down manifold with the single Zenith carburetor. This was not without problems. I had to make a carb heat system. Turned out pretty cool I think. Running the engine, I couldn’t get the plugs to look the same during carb adjustments. Found out the intake manifold flanges were warped causing vacuum leaks. Made them flat and cured that issue. Runs great. This engine is supposedly 40 hp at 3200 rpm. It’s bore and stroke are 94 x78. Compression is 141 and 145. Pulling the prop through slowly you can feel no leak down. I do not feel like it has excessive blow by. Now.... after doing Leonard’s, suggested 4 minute WOT test, I have discovered my oil separator set up is not working the way I had hoped. After two and a half minutes oil spewed out the filter. I am at my wits end over this issue. Somewhere in the manual, Mosler talked about a new oil filler/ breather apparatus, no picture of course. Top of the engine has a 1 inch hole, the 1/4 inch hole I put there. VW engines have a much larger hole. The smaller the hole, the greater the velocity of stuff coming out. Maybe harder to separate oil out? Don’t want to tear down a great running engine at this point, but I’m thinking about making the hole much larger, slowing down the escaping gasses, so some escaping oil can fall back in easier. Don’t know if I’m on the right track here. I feel like a two cylinder engine that is missing the other two pressure balancing cylinders, with a very small crankcase, is going to present certain PCV issues. There’s got to be a way. Some pics of the engine top and my failed separator.

[Mark Kramer]

For some reason, the forum will not let me post photo’s. Says to contact forum administrator. I have no idea how to do that.

[Kamcoman77]

Mark, perhaps nobody has mentioned this, but there is usually a plate or wire mesh under the Hummel breathers to keep oil from being thrown off the cam gear directly onto the reed assembly. On the VW case a stock baffle plate works, but on the Mosler there is no room for this plate. Like Dan suggested, is there any place on the Mosler case a new hole could be drilled, large enough to put your breather in, that is not in line with the cam gear or crank throws? I'm putting my breather on the side of my VW case and not using the stock location.

[Dan_]

For some reason, the forum will not let me post photo’s. Says to contact forum administrator. I have no idea how to do that.

From the main menu...

https://www.eaglersnest.com/forum/index.php?action=contact

Seems like you posted some before... what has changed..?

[Dan_]

Call Scott Casler and see if you can ship your engine to him.  It will come back ready to fly...

HUMMEL ENGINES

5464 E. STOREY ROAD

COOLIDGE, AZ  85128

(520) 723-5283

OWNER:  SCOTT CASLER

[Mark Kramer]

Yeah I get the deflector plate in the VWs. Wish I could post pics, because you could see at the bottom of my last set up, I had a 1/2 in copper elbow that went inside the engine facing away from the timing gears. I think the gases moved too quickly through that portion into my separator tank to allow some oil to gravity back in. I have read some stuff about German systems where they say you can have a separate drain without a check valve as long as the oil returns below the oil level in the crank case. Just thinking out loud here but, if the pressure has a easy way out the top of the engine, why would it push the oil up to the same height as where the air is escaping? Separating the oil from the air coming out isn’t the difficult part, its getting the oil back in to my 1.25 qt capacity sump. I think a separator tank sitting over a very large hole in the engine top would slow down the pressure movement enough to allow oil to fall back in. The hole under a VW breather is 3 or 4 times the area of mine. Not sure if I’m ready to cut such a large hole yet. There also doesn’t seem to be anywhere else on this Mosler case to make a hole for a breather. My engine runs great, and I can’t really afford sending it to Scott, so hoping to get ideas from folks on the forum.

[Mark Kramer]

Here are a few pics. One shows the small hole in the top of the engine. One shows my separator/catch tank, the other shows my home made exhaust and carb heat box. I think the small hole might be part of my problem.