Lawn Tractor Engine Problem

[Pavel314]

Not exactly home repair but closely related. I have a 7-year-old Craftsman lawn tractor with the Briggs and Stratton 24 hp 2 cylinder engine. It's bee n well maintained, regular oil and filter changes and so on.

Saturday afternoon I cut the front grass. Sunday morning I mowed the side a nd back lawns and the paths in the vineyard. Probably 20,000 square feet to tal for both days, no problems.

Shortly thereafter, I was mowing the weeds in the area we use for the pumpk in patch to prepare for tilling when the engine just quit. It would still c rank and fired sporadically but wouldn't keep going. I noticed that the fue l filter was about empty, although I'd just filled the gas tank. I got some tools and checked things out. The gas filter was about half full now. When I disconnected the fuel line above the pump and cranked the engine, it pum ped gas several feet with good pressure and volume, so that was working.

I left the tractor and went on with the tilling, as the weeds weren't high and thick enough to tangle in the tiller blades. A few hours later, I went back to the tractor and took off the cowel over the engine to look inside. On a whim I tried to start it and it ran fine as long as I left the choke o ut. It would travel and mow without problem, but as soon as I put the choke in, it would die. Immediately, no sputtering or winding down, just shut ri ght off.

Usually when something like this happens, I've found that the carb is loose , allowing excess air through the gasket between the carb and block, and th at tightening the carb bolts solves the problem. I haven't gotten around to that yet, ran out of day.

Any other ideas on what the problem could be? Ironically, I already have a lot of tune up parts on order for the engine (filters, plugs, etc.) which s hould arrive before next weekend.

[Dean Hoffman]

Cut rest.

Something plugging fuel port in fuel tank occasionally? Plugged vent in gas cap? Intermittent plugging of carburetor ports?

[Unquestionably Confused]

On 5/5/2013 8:51 PM, Dean Hoffman > wrote: [snip]

I'm thinking along the same lines.

Get a can of "Start Your Engines" and give it a shot. Might clear out any gunk that's causing your engine grief. (Started using this stuff last year and it's worked wonders on some little used (woodchipper, gas powered hedge trimmer, tiller, etc.) Can't hurt.

IF that doesn't do it or if the situation continues, I'd look at crap blocking the fuel intake in the gas tank. That comment about the fuel filter has me wondering.

When you talk about the choke being out to keep it running, that sure tells me it's starving for fuel. If there's a blockage (intermittent or not) the fuel pump can only pump out what it gets at it's intake port. By running it super rich (choked) you;re compensating for that.

[Stormin Mormon]

My sense is that the screen inside the tank is clogged, not allowing fuel down the fuel line.

That, or the carb to engine gasket. BTW, it's a good idea to remove the carb, and lightly coat the carb with Permatex IIb non hardening gasket goop. Which is totally messy, and cleans off with drygas alcohol. Try to get it only on the carb gasket.

Saturday afternoon I cut the front grass. Sunday morning I mowed the side and back lawns and the paths in the vineyard. Probably 20,000 square feet total for both days, no problems.

Shortly thereafter, I was mowing the weeds in the area we use for the pumpkin patch to prepare for tilling when the engine just quit. It would still crank and fired sporadically but wouldn't keep going. I noticed that the fuel filter was about empty, although I'd just filled the gas tank. I got some tools and checked things out. The gas filter was about half full now. When I disconnected the fuel line above the pump and cranked the engine, it pumped gas several feet with good pressure and volume, so that was working.

I left the tractor and went on with the tilling, as the weeds weren't high and thick enough to tangle in the tiller blades. A few hours later, I went back to the tractor and took off the cowel over the engine to look inside. On a whim I tried to start it and it ran fine as long as I left the choke out. It would travel and mow without problem, but as soon as I put the choke in, it would die. Immediately, no sputtering or winding down, just shut right off.

Usually when something like this happens, I've found that the carb is loose, allowing excess air through the gasket between the carb and block, and that tightening the carb bolts solves the problem. I haven't gotten around to that yet, ran out of day.

Any other ideas on what the problem could be? Ironically, I already have a lot of tune up parts on order for the engine (filters, plugs, etc.) which should arrive before next weekend.