Tech Support Forum - View Single Post - B&S 11HP tractor runs 15 minutes and dies

mks113 · 06-24-2009, 11:30 AM

I've got an old lawn tractor with a B&S 11HP engine. Last year it started to die after running for 10-15 minutes.

This spring I replaced the coil and had the carb and air filter cleaned. I replaced the battery as well.

It worked for a while, now it is back to the old pattern.

The pattern is that it runs fine for a while, then I detect a slight loss of power, then it dies very suddenly. As it dies the governor slams the throttle to full, but there is no response. Even if I flip off the PTO as it dies, it does not recover.

A concern is that it won't turn over after it dies. I thought it was a battery/charging problem as it would start fine after 15 minutes on the charger. Then I realized it would start find after sitting for 15 minutes.

I'm thinking either the engine needs a complete rebuild (is it worth it?) or possibly the exhaust is blocked. I'll check the exhaust tonight. The carb, fuel supply and ignition are all in good shape.

Any suggestions? Should I break down and buy a new mower?

06-24-2009, 11:30 AM	#1 (permalink)
mks113 Registered User Join Date: Jun 2009 Posts: 3 OS: win xp SP3	B&S 11HP tractor runs 15 minutes and dies I've got an old lawn tractor with a B&S 11HP engine. Last year it started to die after running for 10-15 minutes. This spring I replaced the coil and had the carb and air filter cleaned. I replaced the battery as well. It worked for a while, now it is back to the old pattern. The pattern is that it runs fine for a while, then I detect a slight loss of power, then it dies very suddenly. As it dies the governor slams the throttle to full, but there is no response. Even if I flip off the PTO as it dies, it does not recover. A concern is that it won't turn over after it dies. I thought it was a battery/charging problem as it would start fine after 15 minutes on the charger. Then I realized it would start find after sitting for 15 minutes. I'm thinking either the engine needs a complete rebuild (is it worth it?) or possibly the exhaust is blocked. I'll check the exhaust tonight. The carb, fuel supply and ignition are all in good shape. Any suggestions? Should I break down and buy a new mower?