Gas in Oil?

#1
I picked up a early model Bonanza 1300 with a Tecumseh H35(1967 I think). Checked compression and got about 110psi. I bought a cheap Chinese knock-off carb, replaced the oil (21oz), set the timing(.065" BTDC), and points(.020").

Pulled and pulled and got it to run but it was bucking and sounded pissed.

Today I check the oil and its flowing out the crank case, it has to be gas in there, but how? If the cheap carb float sticks open how is it going to push gas up the intake? Secondly, wouldn't it flow out the back of the carb choke side? (No air filter yet).

If its getting into the case from the piston rings, would I have 110 psi compression?

I'm a Network Engineer, not much of an engine mechanic. I need help

Thanks in advance.

Brandon
 

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mustangfrank

Well-Known Member
#2
I picked up a early model Bonanza 1300 with a Tecumseh H35(1967 I think). Checked compression and got about 110psi. I bought a cheap Chinese knock-off carb, replaced the oil (21oz), set the timing(.065" BTDC), and points(.020").

Pulled and pulled and got it to run but it was bucking and sounded pissed.

Today I check the oil and its flowing out the crank case, it has to be gas in there, but how? If the cheap carb float sticks open how is it going to push gas up the intake? Secondly, wouldn't it flow out the back of the carb choke side? (No air filter yet).

If its getting into the case from the piston rings, would I have 110 psi compression?

I'm a Network Engineer, not much of an engine mechanic. I need help

Thanks in advance.

Brandon
Did you set the carb to basic specs? Don't trust them to be tuned out of the box.
 

mustangfrank

Well-Known Member
#4
I did 1.5 turns out on the main adjust seat (Bottom of bowl), and 1 full turn out on the idle speed screw (Side).

View attachment 278008
That should get it started and running decently. Repeatedly pulling it over and not starting will cause a little leakdown of the gas into the oil. Worth checking the float level just in case it is high. Sounds like spark issues...new plug?
 
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