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craftsman lawnmower engine


roconnell's Avatar
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08-17-06, 05:50 PM   #1  
craftsman lawnmower engine

I have an 11 HP mid 1980's rider lawnmower. The motor starts fine and runs well, but for only a short time, I then start mowing and the engine then begins to putter out and dies after 60 seconds or so, then I disengage the blades and turn the key and it starts up no problem after choking, I put it back at the same speed on the throttle that it was just puttering out at and it runs fine for another 60 seconds or so, at no point do I touch the throttle after it is started and then it putters out again, it sounds like a carbuerator or gas line problem but I am not sure where to begin my troubleshooting any help would be greatly appreciated. Thank you

 
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08-17-06, 07:09 PM   #2  
I've moved your question to a forum where you are more likely to find a meaningful answer.


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cheese's Avatar
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08-17-06, 10:13 PM   #3  
Try it with the gas cap loosened. it might be vaporlocking.


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God bless!

 
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08-18-06, 04:11 AM   #4  
If the fuel cap trick yields no improvement check for good fuel flow from the fuel line where it attaches to the carburetor. Have a coffee can ready, loosen the fuel line clamp and pull the fuel line off the carb and allow fuel to drain into the can for 15-20 seconds watching for steady flow at a reasonable rate. If your machine has a fuel pump - in other words, not gravity fed - then you'll need to crank the engine over with the electric start by first removing the spark plug (to eliminate compression) and allowing to crank for 10-15 seconds and again watching for good flow and rate. If you have insufficient flow, you'll want to replace the in-line fuel filter and fuel shut-off valve as well inspect the flow at the gas tank outlet. I'd suggest replacing the fuel line as well, in its entirety. If you determine you have good fuel flow then it's time to have a look inside the carburetor for trash/varnish.

 
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08-18-06, 08:41 AM   #5  
Puey, I am curious why you recommend replacement of the shut-off valve if fuel flow is a problem?

 
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08-18-06, 02:47 PM   #6  
Over time, with poor maintenence procedures, varnish will build-up in the fuel line, filter, shut-off and carburetor. The shut-off valve has a relatively tiny passageway and will clog up easily thereby reducing the flow to a trickle.

 
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08-18-06, 05:55 PM   #7  
Craftsman stalling

It is gravity fed, I pulled off the fuel line and filter it appears to be unclogged, how much fuel should be coming from the tank, right now it is a slow steady stream, should it be stronger than that? It is still doing the same things and it tends to die out more when I am moving forward in gear and when I have the bladed engaged, if I I press the clutch or disengage the blades it tends to bring it back, Thanks, everyone has been very helpful

 
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08-18-06, 11:24 PM   #8  
As long as it's coming out faster than a trickle, it's probably ok. The stream should be almost as big as the inside hole in the fuel line. If this is ok, then you probably need to go into the carb and clean it out.


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08-26-06, 10:24 AM   #9  
still puttering out

The weird thing is that the engine revs real high after I start it and then it dies, like it is almost getting too much fuel, is that possible? I checked the spark plugs and they are fouled, cleaned the plug with a wire brush and put back in, still having ame problem, engine starts and runs like a bat out of hell for 5 seconds and then putters out, alot of white smoke as well, thanks for any help

 
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08-26-06, 10:37 AM   #10  
The white smoke indicates that you likely have fuel in your engine oil thereby overfilling the oil and hence the smoke. Pull out your dipstick, wipe it down, re-insert it and check the level as well as smell for a gasoline smell to it. If so, you will need to remove the carburetor and do a soak and reconditioning of it with the proper Briggs carb kit. Post back with your findings and also the engine ID numbers which will be stamped into the flywheel shroud, just above the spark plug area, most likely.

 
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08-26-06, 12:04 PM   #11  
thank puey, I checked the dipstick to see what is going on and it did smell like gas, so I drained the oil, before I drained the oil I also noted that it was backfiring alot and I can see some flames coming out of the exhaust, also if I applied the choke it seemed to keep the engine from dying temporarily, I could not locate the engine # right now I have to leave to a BBQ, thanks for all your help

 
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