Repairs briggs 14hp. twin backgfires thru exhaust

pggarden

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Recent mowing a strange clattering noise. seemed to run well. Shut engine offf and when i restarted the engine it backfired thru the exhaust breaking a seam in the muffler. ???
 

briggs

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these are the things that are hard to pin point ...It could be a carb prob dirt and crap in the fuel sys water ,hole in float ..Dose it still run will it start can you smell lots of fuel hows the air filter it could also be a timing issue need more info please
 

KennyV

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Along with what briggs said...
I would check the cooling system... are all the air channels open and unobstructed, including the blower itself...?
f this only happens after it has been running...
It sounds like you may have an exhaust valve sticking...
If your cooling system is clean and working , switch to a premium, high octane, fuel... that could lower the exhaust valve temp enough to keep it from hanging... :smile:KennyV
 

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triniphen

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running rich, or shutdown from high throttle, the spark is killed but the cylinder pumps in fuel for a few more revs. Upon start up it will pop off a few. how does it run otherwise? got power?
 

pggarden

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The backfiring is not a great concern but the clattering noise in the motor does. the tractor was running fine then I heard the clattering, like a tappet sound. Before the clattering noise the motor did not backfire. It seems to have power. This a replacement motor on a case 444 and it is not very old. I am not running the tractor for fear of damaging something in the motor. A previous thread mentioned a sticking exhaust valve. While the motor was idling I removed the oil filler cap and there was a noticable like an exhaust coming out of the opening. Is there a way of determining if indeed it is a sticking exhaust valve? Vacuum check? cheers.
 

Walt 2002

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Buy a can of Marvel Mystery Oil and use according to instructions on the can. IF a valve is sticking, it will clear it up.

Walt Conner
 

pggarden

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I put marvel mystery oil in the gas and oil. I ran it for 20 minutes. shut the engine off and restarted, no backfire and no clattering. BUT when I put it in drive the clattering was there, both forward and reverse. when I take it out of drive the clattering stops. SO, it apppears that it is not the enginne but perhaps the hydraulic system or could it be the connection between the hydraulic pump and the motor? This is a replacement engine. the person that installed the new engine may have had dubious abilities. How could the Marvel oil change the location of the clattering? Hydraulic oil is full. Oh, the mysteries of life and machine!!!
 

pggarden

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I occured to me that putting it in drive puts a load on the engine, so it still could be the engine...
 

pggarden

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Buy a can of Marvel Mystery Oil and use according to instructions on the can. IF a valve is sticking, it will clear it up.

Walt Conner
Thank you, I believe it worked. I can barely hear a clattering.
 

gregjo1948

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A backfire happening on shut down could be caused by a faulty fuel solenoid. If you listen closely when turning on the ignition, you should hear a little click from the carb area. Usually if you hear it, it's working. gregjo1948
 
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