Engine stops when hot

foltzr · Jul 19, 2010

I have a Scotts/JD lawn tractor with a 20 HP B&S Inteck Twin engine. The thing runs fine for about an hour then will die as if out of fuel. Applying the choke will help me get back to the barn but will not keep it running. I let it sit and cool down for about twenty minutes and it will start and work fine for maybe ten minutes and then will die as before... like it is out of fuel.

I have replaced the short fule lines and the filter and put onm a new fiel pump but the problem is still there. It will run fine for awhile then stop as if starved for fuel.

Any suggestions?

Treemonkey1000 · Jul 19, 2010

Are all of the cooling fins clear on the head? Is the cowling clear? Air filter clean (not that it will cause that problem) Next step is the ignition components breaking down after heating up. I would lean towards the ignition module is failing.

mrutkaus · Jul 19, 2010

Enough oil, fresh oil?

Could be engine heating up and freezing.

Mike

Jim Thompson · Jul 19, 2010

If pulling the choke out partway allows you to limp back to the barn, I would to continue to suspect a fuel problem. You might check for an obstruction in the fuel tank, possibly trash that sometimes blocks the pickup. Also, insure that there isn't even a small amount of water in the tank. As someone else suggested, check that everything associated with engine cooling is as it should be- to eliminate vapor lock as an issue.

Good luck.

Jim

rjkobbeman · Jul 19, 2010

I have a Scotts/JD GT 2554 that I bought at The Home Depot. In the beginning I had problems with it just dying. Finally, I realized the fuel filter was empty. OK... out of gas. I opened the gas cap and looked inside and the tank was half full. (Half full not being the point... just that it had fuel.) I looked back at the fuel filter and it was full.

Basically some sort of vapor/fuel lock.

Did this for a several years intermittenly... then the problem just went away. Can't explain it... but the problem was not severe enough and did not happen enough to warrant a full fledged investigation. The problem was also hard to reproduce.

CharlieS · Jul 19, 2010

is the problem more prone to happen with a fuller fuel tank? or does it happen quicker when the tank is full vs a lower fuel level? Quite possible its vapor locking but check your fuel tank cap vent. If it cant vent air into the tank to replace used fuel, it cant flow fuel out of the tank after a vacuum starts to form. (think soda straw full of water with your finger over the end)
Loosen the cap so it can suck some air around the cap seal and see if it still occurs. with the time it takes to loose fuel flow because of vacuum buildup in the tank could make it seem like its a heat/quit running scenerio.
Likely if an engine dies because its overheated, piston/cylinder damage will occur, and in worst case scenerios, you're going to have an engine sieze.