briggs and stratton 17 hp mower gets stuck on compression
#1
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briggs and stratton 17 hp mower gets stuck on compression
my briggs 17hp rider mower flywheel gets stuck on the compression stroke even after ive adjusted the valves to .004 and.006 and i dont know what to do next

Last edited by keystart; 06-20-12 at 12:59 PM.
#9
Try adjusting the valves even closer to zero clearance. I think your compression release is worn out or broken. If this is the case, a closer adjustment is about the only thing that may get it going without opening the engine, and is only a temporary band-aid. While you rotate the engine clockwise from the top with the valve cover off, watch the intake valve for a little tiny movement just before the top of the compression stroke. If there is none, it's the compression release, which requires engine removal to repair.
#11
It would need a cam/lifter kit/set. They run about $90 for the set, plus a crankcase cover gasket for re-assembly. 9 times out of 10, a proper valve adjustment is all that is needed. Are you 100% certain that they are adjusted properly?
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I just had a friend's intek with that problem and valves were right on spec. Turned out to be a bad main battery ground at the chassis. Not at home so can provide link but I found a very good MTD article on testing for voltage drops that cause slow cranking.
found the article here:
http://service.mtdproducts.com/Train...electrical.pdf
found the article here:
http://service.mtdproducts.com/Train...electrical.pdf
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may I suggest that you adjust the intake valve back to .003-.005 and with plug out turn the engine by hand in the correct direction and watch the intake valve. As it closes watch for a little hop.
#18
If you see the hop, then the compression release is working. You have either valve adjustment problems, starter/voltage/battery problems, or fluid in the cylinder.
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thanks i tightened the exaust a little and eased off the intake and it started right up the intake valve is way tighter than .003 so do i still need a new cam or is it good???
#20
I think your cam is good, you just have some problems getting them adjusted properly. What is the clearance? As long as it is more than zero, it shouldn't hurt anything.
#24
I can't tell you if it will be ok or not. You're taking a risk with it that tight, and you may or may not burn the valve.
#27
Combustion gasses go past the valve, burning away pieces of the metal until it ruins it and loses compression.
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i have looked for voltage problems by hooking up a multimeter to my battery and it showed no drop i finally looked at your link because my cpu wasnt cooperating and it told me that i need to hook the multimeter up to the starter is this correct?
#35
Yes, that is probably directly related to your problem. Fluid in the cylinder. Smell the oil for a gassy smell.
#38
The gassy smell means that your carb is leaking fuel into the cylinder when it's not running. The gas seeps past the rings and gets in the oil, thinning the oil. Then the oil works it's way into the cylinder and it raises the compression too high for the starter to turn the engine (fluid in the cylinder I mentioned earlier). The carb needs repair and the oil changed.