LonnieMcc

Hey guys,

Want to run something by yall.

A flying buddy of mine gave me a OS LA 46 engine the other day. I am not sure as to how old the engine is, and I don't think he remembers either.

Anyway, I set it up on a old trainer today to test run it. Once I got it primed and stared checking the throttle, I noticed it was not moving like it should. After looking further I found the throttle barrel screw was loose. Fixed that and all is fine.

But when I started the engine up and tuned it, I noticed fuel coming out the engine under the head. At first thought I was seeing things, so shut it down cleaned it off and restarted. And again the fuel showed up again.

So at this point I am not sure if it was leaking at one point while he had it in service, or after sitting in a box for awhile caused something to change.

What would be the best way to fix this, or would it be ok to run the engine the way it is??

I did let the engine run for awhile, guess I burned about 4 oz's watching and checking, and the engine ran great and sounded great.

Thanks for any and all help.

Jim Thomerson

That shouldn't be. First thing would be to check if the head bolts are tight. If they are, take the head off and see why it is leaking. It may be a bent gasket or something. A friend once had a new engine with a similar problem. I took the head off and found a brass shaving between the head and the head gasket. Removed it and all was fine.

Sport_Pilot

It may have a shim but no gasket.A fine finish machined surface is all they use gaskets are not used. So inspect the suraces for corrosion, scratch's, or pitting. Small inperfections could be polished out. If not RTV should work as a sealer. Iam not sure about that because I have not tried this.

LonnieMcc

I checked the head, and it was tight. However, I did go ahead and remove it anyway just to see. I didn't polish anything on the head and cylinder, but I did wipe everything down. It seemed to be smooth, but did have like a discoloration pattern, on the side of the head where the leak is.

I am going to run the engine again tomorrow and putting the head back on. Who knows, it may have sealed better and won't leak now.

1QwkSport2.5r

It could be fuel stand off. The carb is "spitting". At rich fuel mixtures, carbs tend to spit and that "spit" ends up stuck to the front of the cylinder. At flight-mixture settings, it will still spit but less. I had the same thing happen to me when I fired up my Jett BSE .35 for the break-in runs. There was oil all over the front of the engine after a 4min run. Checked the head and it was tight. After leaning it down some there was no more oil all over the engine. The OP's issue sounds normal to me.