Diesel doesn’t go in these ....

[Portajon]

Hello folks, thanks for letting me on your forum and thanks in advance for any help offered.
So the wife was trying to be helpful and mow the lawn. She grabbed the can we had just filled with diesel the day before for our boats Yanmar and filled the Briggs 17.5 in our Huskee mower. She said it made a round or two in the yard before it started making funny noises and quit.
Took me a minute to figure it out, as a half and half diesel / gasoline mix is sort of hard to peg until you get a little on your fingers ...

Anyway.... after a few hours trying to get her going, I went and picked up a new carb. She was smoking and back firing and would not run. After new carb... same thing. I kept thinking that it was diesel still in the system until after two days of fooling around, I have figured out that it’s blowing oil.
So what happened? I expected it to smoke for a bit and even a carb replacement, but what went wrong for the motor to now be getting motor oil into the fuel mixture? What broke and why ?
Thanks again. Look forward to the thoughts on this one.

 

[dougand3]

Gravity fed carb? Did you check oil level? is it high? Diesel is a lube - could have slipped by the needle/seat and landed in the crankcase.

 

[Portajon]

Gravity fed carb? Did you check oil level? is it high? Diesel is a lube - could have slipped by the needle/seat and landed in the crankcase.

Oil in crank case looks good. No smell of fuel and level is right.
When I pull the plug and turn it over, I can hold my hand in front of the hole and it is definitely motor oil being pushed out in the fuel mist.

 

[MParr]

First, pull the plug and see if it will spin freely.
If so, change and gap the plug. Then, install.
Second, pull the tank and empty.
Third, make sure the fuel lines are clear of liquid.
Fourth, install new fuel filter.
Fifth, clear the breather hose.
Sixth, change the oil.
Finally, put some high octane in it and give it a whirl.
If your air filter is wet, you will need a new one.
I almost forgot. Drain the carburetor bowl.

 

[Portajon]

First, pull the plug and see if it will spin freely.
If so, change and gap the plug. Then, install.
Second, pull the tank and empty.
Third, make sure the fuel lines are clear of liquid.
Fourth, install new fuel filter.
Fifth, clear the breather hose.
Sixth, change the oil.
Finally, put some high octane in it and give it a whirl.
If your air filter is wet, you will need a new one.
I almost forgot. Drain the carburetor bowl.

Yes, already drained tank and installed a brand new carburetor.
Going to change the oil this morning and see if that helped

thanks.

 

[MParr]

Yes, already drained tank and installed a brand new carburetor.
Going to change the oil this morning and see if that helped

thanks.

I hope that you cleared the fuel lines.
Installed a new fuel filter?
Drained the bowl on the new carburetor? There probably wasn’t that much wrong with the old one. Could have been cleaned.
Installed a new spark plug?
Did you clean the vent tube going into the valve cover?

 

[Portajon]

I hope that you cleared the fuel lines.
Installed a new fuel filter?
Drained the bowl on the new carburetor? There probably wasn’t that much wrong with the old one. Could have been cleaned.
Installed a new spark plug?
Did you clean the vent tube going into the valve cover?

The solenoid on the old carb bowl was cross threaded from the factory. A nice, long ribbon of monkey metal threads came out with it when I removed it to clean the bowl.
Something far more than the obvious went wrong. There is a hole in the piston or the rings went away .... I have back pressure and white smoke coming from the crank case vent tube and oil filler. I don’t know how long she ran it on the diesel / gas mixture but long enough for something critical to break. I’m thinking it got really hot.

 

[Portajon]

Head gasket ? ..... I dunno, but gotta tear it down. This is a dang nice mower with little wear and use and I’m just sick about it.

 

[Portajon]

 

[dougand3]

There you go!