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Compression release? - Newer Briggs Vertical Shaft Engine


PhanDad

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Looking for some help/understanding on a starting issue with a neighbor’s 4 year old Crapsman tractor.  Engine is a single cylinder Briggs OHV vertical shaft.  
Tractor was ran out of fuel and went over speed when mixture went lean. Refueled and tractor won’t start. Starter won’t turn the engine over. Turning engine by hand, moving toward TDC on compression stroke, is very hard.  Seems much harder than my old cast iron single cylinder horizontal Briggs. 
Using my 7016H (has a fresh battery) solenoid wired directly to the problem Briggs (heavy gauge wire), it didn’t want to turn over past compression stroke.  So by hand, adjusted engine just past compression stroke, backed it up as much as possible, and with the extra momentum I could get the engine to turn over and start.  Seems to run fine. Responds to throttle control as it should. 
So what happened?  Did the over speed break a compression release feature?  Does the engine even have that feature?  (I’m only slightly familiar with that feature on the old Kohler K series which I thought had to do with the grind of the camshaft).  
All thoughts appreciated. 
 

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Did some googling.  Compression release sounds like it work as with older engines.  

So I'm thinking the problem is bent push rod(s).  

 

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I have a intek single in one tractor. It was doing same thing you are talking about.  Cdnt figure it out till I saw raw fuel dripping from the muffler one day.  Turned out when the tractor was sitting for a few days, and even just overnight,  fuel was leaking by through the carb and pooling up in the cylinder. With  the added fuel the starter couldnt  pull the piston through the compression stroke.

I put a new fuel shut off in the line and shut it off and let the tractor run some more before I turn it off.  Have not had problems with it since I started this procedure.

May not be your issue, but this is what was going on with mine.

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14 hours ago, SmilinSam said:

fuel was leaking by through the carb and pooling up in the cylinder.

And when this happens the crank case oil is often contaminated with gasoline. Check the oil.

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8 hours ago, kwt said:

And when this happens the crank case oil is often contaminated with gasoline. Check the oil.

That was one of the first things I checked when I realized what was happening. No problems with gas in the crank case. One thing about this particular tractor is that the gas tank is above the engine. Think the float valve was leaking by...

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