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briggs & stratton I/C 11 hp �" [#253707 032601 89090616]:

Posted by hanajack 11 (My Page) on
Tue, Apr 16, 13 at 15:23

Situation: Ran fine a week ago.
Cranked it over many times without hint of starting. Sparkplug wire loose. Started; lots of smoke; would shudder and stall with dirty gas surging out of breather tube into carb intake; muffler wet. Same thing several starts. Removed carb and breather assembly. Assembly also full of gas; more coming out of small hole in bottom of breather/valve spring chamber. Only stopped when drained crankcase of oil/gas.
First question: Could all this gas in the oil be attributed to all the no-start cranking? If not, what?

Flushed crankcase with oil and put in 1 quart of oil [vs. 1 ½ qt.]. With carb and breather assembly off, cranked it over a number of times seeing clear oil spurting out of small hole in breather/valve spring chamber.
Second question: Is this part of a valve lubrication system? If so, that would mean that the chamber would always be full to the top with oil. The onIy possible overflow drainage is a larger hole at the top/back of the chamber. I don’t understand how the “breather” aspect could apply with the chamber full of oil?


Follow-Up Postings:

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RE: briggs & stratton I/C 11 hp �" [#253707 032601 8909061

There should be a small drain hole in one of the bottom corners. Perhaps it is plugged up.

Walt Conner


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RE: briggs & stratton I/C 11 hp �" [#253707 032601 8909061

I think the hole you are referring to [bottom center back] is the one that oil is spurting out of. If oil is spurting out it can't be a drain. There is the large hole at the top center back which would appear to be the drain. Thus, the chamber would stay full to the top with oil all the time keeping the valve springs in oil.
Again, if so, how could the "breather" work.

Also, how would gas get in the crankcase?


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RE: briggs & stratton I/C 11 hp �" [#253707 032601 8909061

Gas gets into the crankcase because the carb float needle is leaking and the gas is running into the cylinder and on into the crankcase. IF the crankcase is over full, of course it is going to blow out the excess. Add a gas line shut off valve and use it when the engine is not running. Replacing the carb float needle MAY work but in old engines like that, maybe not.

Trust me, that chamber DOES NOT remain full of oil when the oil level is correct And the crankcase breather is operation properly. that large hole you are talking about IS NOT a drain, it is for crankcase pressure, vacuum to move back and forth thru.

Walt conner


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RE: briggs & stratton I/C 11 hp �" [#253707 032601 8909061

Thanks for that Walt. It answers a lot.
One more question: Could that small hole have the dual function of squirting oil out to lubricate the valve springs and also be a drain?


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RE: briggs & stratton I/C 11 hp �" [#253707 032601

NO, things are lubed via oil vapor, that is strictly a drain, return.

Walt Conner

This post was edited by walt2002 on Fri, Apr 19, 13 at 19:52


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RE: briggs & stratton I/C 11 hp �" [#253707 032601 8909061

Don't want to beat this to death Walt, but with only 2 pints of new oil in the crankcase [1 pint short], oil does spurt out of that hole when cranking it over. I guess I'll just put it back together and see what happens.

Re: the previous gas in the oil -- I'm thinking of bending the tab on the float [slightly] to put more pressure on the needle.


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RE: briggs & stratton I/C 11 hp �" [#253707 032601 8909061

Time to stock up on the popcorn!


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RE: briggs & stratton I/C 11 hp �" [#253707 032601 8909061

I'm a little slow and don't get: Time to stock up on the popcorn!


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RE: briggs & stratton I/C 11 hp �" [#253707 032601 8909061

That's for the rest of us to snack on while you try to figure out why the engine lacks power, surges or simply won't run.


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RE: briggs & stratton I/C 11 hp �" [#253707 032601 8909061

Took the carb and breather completely apart. Precise cleaning, made gaskets, etc. Runs like new [bought in 1985, $2,500].

Thanks for the help!


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