help! , this is driving me crazy

[snapperlt16]

Yes i have a 402437 16 horse opposed twin briggs engine on my snapper , a few weeks ago oil started shooting out of the #1 cylinder breather tube but engine was running good , i took the pto off and realized the shaft oil seal was pushed in so i replaced it, get everything back together and it fires up no oil shooting out but gas is coming out the top hole in the carb, so today i rebuilt the car and fuel pump and its still doing it, the float bowl has no leaks and the needle is seated, i tried adjusting float height but still nothing, what is causing this? It runs for about 20 seconds then it starts doing it

 

[ILENGINE]

Either the float valve isn't sealing as you are thinking or the gasket between the air cleaner and the carb is turned incorrectly and is blocking off the vent holes.

 

[snapperlt16]

I was running it with the carb by itself the aircleaner assembly was off

 

[snapperlt16]

I had the aircleaner base on it just not the filter

 

[ILENGINE]

A leaking needle valve shouldn't take 20 seconds to start overfilling the carb, especially with a fuel pump. With the air cleaner off, look at the top of the carb and there should be two holes toward the front of the engine. Can you see down through them into the carb a short distance. If those holes get plugged off while cause a siphoning effect.

also make sure you don't have gas in the oil. Because the carb leaking can cause that, which could be related to oil squirting out of the breather.

 

[snapperlt16]

Ok ill check first thing in the morning and let you know the outcome, thanks for the input i really appreciate it!

 

[snapperlt16]

First thing i did was drain the oil there was fuel in it, took the carb apart and cleaned it pretty good, i applied light air pressure to the inlet for the fuel in the bowl and the seat seems to be working, it has to be a carb issue when i drain the bowl and fire it up it runs fine until the bowl is filled then it overfills, I cleaned the carb 3 times, what else could be causing this? I wish i had another carb laying around to try out

 

[ILENGINE]

You didn't happen to shake the float and make sure there isn't gas inside the float causing it to sink.

 

[snapperlt16]

There wasnt any fuel in it , i should let it soak in a bucket to make sure but sounds 100% dry to me

 

[snapperlt16]

i disconnected the vacuum. line and plugged it for the fuel pump and put the gas tank above the aircleaner and it runs fine and doesnt overflow, once the vacuum is hooked back up it floods, It had a bunch of blue/white smoke out of the num 1 cylinder but cleared out, i hooked up a vacuum guage to the vac line for the pump and it fluctuated in the zero mark, the bottom end sounds a little noisey but i was told by someone that its common on the old opposed engines but not sure if that's true