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Engine Compression Question


scott.T.'s Avatar
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09-01-02, 01:12 PM   #1  
scott.T.
12.5 Briggs & Stratton 4stroke...don't have enough Compression?

Hi, I have a 12.5 Electric start briggs and stratton 4stroke...I think the Compression is much lower than it should be...my freind checked it and said it was about 50lbs? when it should be well over a 100... I'm trying to figure out if its worth tearing the Engine apart to try and fix the compression problem...or should i just move on and buy a new engine or mower....

We both said its low compression is whats wrong...since its getting fire,air, and gas.

and help would be wonderful.

Regards,
S.T.

 
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09-02-02, 03:31 PM   #2  
Hello scott!

It depends on what is causing your compression loss. Normally, a briggs 12.5 hp engine will start with minimal compression, although it may not run worth a flip, smoke, knock, etc... Normally it will at least crank up. What has been checked, and what is the engine doing?


"Who is John Galt?" - Ayn Rand (Atlas Shrugged)

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09-02-02, 09:31 PM   #3  
scott.T.
Good news...i took the whole engine apart and I couldn't believe the Carbon build up on the piston it self and on the intake and exhaust vavle...so much that the engine wouldn't even crank up...after getting all of that carbon off and really cleaning every thing i could think of with gas..and a rag..I put the fresh cleaned engine and Carb back together and with a little starting fluid...on the first try it fired right up and ran great....runs like a champ..and don't need starting fluid to start...so I guess everything is working great....but i would still like to recheck the compresson, after i've done all of this...


 
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09-02-02, 10:59 PM   #4  
Generally, if you have a compression problem, you will have so much blowby that the engine blows oil into the intake and causes it to smoke. It sounds like everything is OK. Good job! Glad you got it going!

Let us know if we can help you in the future!


"Who is John Galt?" - Ayn Rand (Atlas Shrugged)

God bless!

 
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