Craftsman snow thrower stalls

[tom_sawyer70]

I am attempting to help to get a snow thrower working. :-) It is a Craftsman snow thrower (model 536.884330, code 0323M) that starts and then after about 15 minutes of running, stalls. Sometimes, we can get it restarted, but even then it seems to stall every few minutes until eventually it will not start.

If we wait a little while and come back an hour or so later, it restarts.

The gas mixture is fresh. What would inhibit it from continuing to run? Would replacing the spark plug be next on the list or do we need to look to the carb?

I don't know how often maintenance has been done on the machine...I would guess it is in need of a tune up.

Is there a site that would show how to disassemble and clean the carb on the machine or a general tune-up list (I think I remember seeing that the model 536* indicates a Murray-built machine)? I've been searching for one, but would appreciate a link if you have one that has been useful to you.

Thank you, Dave

[Russ]

Just wait until it's a little warmer outside...like spring.:)

[tom_sawyer70]

We set the choke when starting and ease off as it warms up.

[Gino]

Do you have his number handy? I have a few things I'd like to say to Bob.:)

[Roby]

These are exactly the symptoms of a plugged vent in the gas tank cap.

Try running with the cap removed.

Roby

[tnom]

I had a similar problem from a Craftsman model 663 two stroke engine from the late seventies. I tried to look up your model but could only determine that it may be from the same time period.

I fixed my random shut down for no apparent reason problem by disassembling the bottom of the carburetor and cleaning all the accumulated gunk out of the bowl. Be careful of the paper thin rubber gasket. I was able to do this without buying any new parts. It's still working today at an age of about 26 years.

[toller]

It sounds like you are not using the choke properly. I am sure you are and it is something else entirely, but maybe...

[toller]

Just for fun, ease off slower. Can't hurt. I don't know off hand what Craftsman model I have, but I have to ease off the choke over a much longer period of time than really seems reasonable, or it stalls on me.

[Rescate]

Phone up Bob Vila.

[Tony Hwang]

Hi, Or carb is not adjusted properly. Or moisture getting into ignition parts? Tony

[Robert Barr]

On later model air-cooled engines, this behavior can be caused by an ignition module that fails when hot. Once the module cools off -- even for a few minutes -- the engine will run OK for another short period.

You don't even mention what brand the engine is, but every make has pretty much the same style of solid-state ignition module, and any of them can develop this problem. It's an absolute bastard to troubleshoot, because anything else you mess with seems to help -- for a while. Until the module heats up again and stalls the engine.

Pull the flywheel housing and the module will be right there. It looks like the magneto of older days. Be prepared for an obscene replacement cost, which is why I keep several of these lying around for diagnostic purposes. A scrap mower engine or two can come in handy as a source of parts.

[Mark]

I had a similar problem....

turns out the gas cap has a TINY hole in the top to allow air to enter the gas tank so the gas can leave. With all that snow flying around it is easy for some snow to fall in the hole, freeze and clog it shut.

I drilled 4 somewhat larger holes in the side of the cap and it seems to have fixed it for me. (With the cap off and clean of gas, don't bring your electric drill near a gas tank please....)

I don't think you can have a vapor lock problem when it is 25 deg F out.

[Stormin Mormon]

Sounds like you either have

1) a fuel line too close to the motor (vapor lock) 2) or you have valve clearance problems. My guess. Requires dissembling the engine, and grind some metal off the camshaft end of the valve. I've done this, but it's a bit involved. Learned about this in the small engine course I took umpteen years back. 3) Third answer, bad vent in the gas cap. 4) answer, bad windings in ignition coil.