I have a 25 yr old craftsman lawn mower. Lately the engine has been giving me some issues.

I pump the primer bulb a few times start it up and it starts fine. Runs for a few seconds at full throttle and then sputters out like it's starved for fuel. It used to be this would happen and after 3 or four tires it would continue to run. Last week it kept dying. I did it about 7 or 8 times with the same result. It has a little throttle control on the side for slow and fast (rabbit and turtle). When I tried putting the throttle on slow, it started up like normal and kept going. I let it warm up a bit and tried fast and it died. Started it up again on slow and started mowing. About 10 min into mowing I put in fast and it stayed running but it seemed like it was surging a bit. When I hit a thick patch of grass, it seemed more susceptible to stalling than normal. I also took the air cleaner off thinking may be it was a air starvation issue but having the air cleaner off had no effect.

I figured may be the carb needs to be cleaned out but I have never done this before on a car much less a mower. Does this sound like a carb issue? Something else? Should I get carb cleaner or can I use brake cleaner or paint thinner to clean it?

Thanks

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Sent from an agnostic abacus

2014 C250 21,XXX my new DD ** 2013 GLK 350 18,000 Wife's new DD**

- With out god, life is everything.
- God is an ever receding pocket of scientific ignorance that's getting smaller and smaller as time moves on..." Neil DeGrasse Tyson
- You can pray for me, I'll think for you.
- When you understand why you dismiss all the other possible gods, you will understand why I dismiss yours.

I took my apart and cleaned the parts with laquer thinner, reassembled it, and it ran like a top. I usually run all the gas out of it at the end of the season, but forgot to do it last year.

I think Ben Hogan is the resident expert of small engine problems here. Maybe he'll offer something helpful.

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OBK #55

1998 Lincoln Continental - Sold
Max 1984 300TD 285,000 miles - Sold
The Dee8gonator 1987 560SEC 196,000 miles - Sold
Orgasmatron - 2006 CLS500 90,000 miles
2002 C320 Wagon 122,000 miles
2016 AMG GTS 12,000 miles

I think it was Tom Walgmuth who said he runs his small engines on lacquer thinner to clean out the carb. I'd give that a try or just give the carb a lot of shots of aeresol carb cleaner when it's running. Sounds like the main jet has some dirt in it. You might be able to pull the main jet out and squirt some carb cleaner directly up into its seat. Lots of small engine carburetors have jets that can be removed by unscrewing the big nut at the bottom of the bowl.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

These days, my first guess would be to check all the rubber parts in the carb, fuel pump, etc, check for clogged strainer, drain and check fuel tank for rust, and so forth.

Around here, the small engine repair shops are making a killing off of repairing yard equipment, that's been screwed up by using ethanol blended gas - not only does it eat up certain types of rubber and plastic, it absorbs water and if left sitting in a metal fuel tank for any length of time will cause it to rust.

Then again, might be as simple as the problem with our Cub Cadet riding mower - acting like it was starved for fuel - turns out the sintered brass air vent on the diaphragm fuel pump was clogged with dirt and old grass - cleaned it out and it ran like a champ.

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Just say "NO" to Ethanol - Drive Diesel

Mitchell Oates
Mooresville, NC
'87 300D 212K miles
'87 300D 151K miles - R.I.P. 12/08
'05 Jeep Liberty CRD 67K miles
Grumpy Old Diesel Owners Club

locate the bowl beneath the carb. there is a 1/2" bolt holding that bowl.

remove the bolt. the nut as a number of holes on it. clean it with one strand of wire from a wire brush. note that on some mowers, there is an additional hole close to the top of it close to the threads. clean that too.

reassemble and it should run like a top.

don't lose the gasket that goes between the bowl and the bolt. without it, the gas will leak out. if it is broken, pm me and i will send you one.

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Ben
1987 190d 2.5Turbo

I'll lay $5 that it's the gasket behind the carb. I've had 3 different old Crapsmen, and each one gave me the same issue, and that was the fix each time.

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1987 560SL
85,000 miles

On a Briggs and Stratton:

Take the bowl off, see if you have water in the bowl. If so the tank needs removed and flushed out. If there is white powdery corrosion in the bowl, the carb is toast.
Remove the main jet and flush with choke cleaner, especially the two very small orfices in the side of the jet,shoot cleaner down into the jet, it will come out the small orfices. Blow out with air. Shoot some of the cleaner up into where the jet goes by bending the plastic tube to fit there.

The main jet is usually pretty easy to get out, the bowl gasket might be swollen and tough to put back, if so, it may need replaced.

If it has a Tecumseh, they usually need a carb.

Off to the garage to do some dissembling. I will report back.

__________________
Sent from an agnostic abacus

2014 C250 21,XXX my new DD ** 2013 GLK 350 18,000 Wife's new DD**

- With out god, life is everything.
- God is an ever receding pocket of scientific ignorance that's getting smaller and smaller as time moves on..." Neil DeGrasse Tyson
- You can pray for me, I'll think for you.
- When you understand why you dismiss all the other possible gods, you will understand why I dismiss yours.

I have 2 Craftsman push mowers, both with Briggs 6.25 engines. Both are the later style with no throttle control. Both have intermittently had this issue. On one unit, carburator cleaning as described above resolved the problem. On the other unit, I found that the only way it would run was by slightly loosening the gas cap. (I think this one might have a gas cap borrowed from a junker, maybe not the right one). The clue was, when pushing the primer bulb, there was no resistance, as if there was no fuel at the primer.

Both units run noticably better with fresh gas. It seems like when this crapahol gas gets to be about 90 days old, it does not run well in the mowers, even though the cars still run OK on gas bought at the same time.

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Palangi

2004 C240 Wagon 203.261 Baby Benz
2008 ML320 CDI Highway Cruiser
2006 Toyota Prius, Saving the Planet @ 48 mpg
2000 F-150, Destroying the Planet @ 20 mpg



TRUMP .......... WHITEHOUSE
HILLARY .........JAILHOUSE
BERNIE .......... NUTHOUSE
0BAMA .......... OUTHOUSE

Ethanol Blended Fuels and Small Engines - YouTube

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OLD & RETIRED
_.... Don't mess with old farts - - age and treachery will always overcome youth and skill! Bulls**t and brilliance only come with age and experience!____________
'96 E320
'79 450 SEL
'78 300 CD

I'll bet if you take the carb apart it will be filled with tan colored goo.

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2001 SLK 320 six speed manual
2014 Porsche Cayenne six speed manual

Annoy a Liberal, Read the Constitution

We used to get them in and clean the carb and jets, flush the tank and it ran great. Then it would come back same way. Customer had water in his container. We always put a tag on the mower about it too. They just tear them off.

I always use Stabil in my small engine gas nowadays.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

That in and of itself, is truly remarkable!

Every Craftsman (pre B&S era) product I've ever owned (motorized, not tools), failed me within a couple of years! Sheared intake or exhaust studs on the 2-cycle versions, and one of the mowers even threw a rod!

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car

With mine, the general demise has been bent cranks. It seems as though they are made out of a softer, weaker steel than other manufacturers. They don't hold up well against stumps.

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1987 560SL
85,000 miles