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compression release


thedancingman43's Avatar
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11-24-10, 01:03 PM   #1  
compression release

I have a briggs engine that I I am trying to get running again. I put on starter motor but the compression release valve isn't working to well. When I opened up the engine I noticed that it looked like the little bump for the compression release to have worn out or something. Here are my questions: should I notice the valve opening when I turn over the engine? Is there a way the compensate for a worn out bump in the compression release valve? Shpuld I buy a stronger starter motor?

 
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38racing's Avatar
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11-24-10, 09:36 PM   #2  
is it a flathead or OHV. Either way valve clearances are important. Did you check them against specs? Aslo make sure your battery has good cranking amps. Model number of the engine would help.

 
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11-25-10, 04:21 AM   #3  
In terms of your questions:

The compression release/relief works on the exhaust valve (normally). It simply cracks it open until the engine starts. From that point on it is inactive. When you turn the engine over both the exhaust and intake valves will open and close.

Should you have a valve that isn't moving at all the problem is likely either the push rod in an OHV (overhead valve) engine or the cam (in either OHV or flat head). Your engine is the latter = the valves not moving would be an indication of a worn out cam or cam gear. There wouldn't be a way to compensate for it. The part at fault would have to be replaced.

 
thedancingman43's Avatar
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11-25-10, 06:52 AM   #4  
well, it is a flathead engine and when i do turn over the on the compression stroke i do hear some air escaping but it is not enough for my starter motor (which by the way is a 120v (that plugs into an outlet) that i took off a 8hp snowblower engine) to get trough with enough speed for the magneto to work. Any suggestions (preferably on the cheap)?

 
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11-25-10, 09:00 AM   #5  
I think your starter motor is your problem. AC motors just don't have enough torque in general. DC starters are capable of much more torque which is needed for starting and engine and the reason they draw so much amperage.

 
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