Craftsman self-propelled mower will not start

Hey all,

This is new territory to me, I would like to get this living again . My neighbor was throwing out a mower and I asked if I could take it he said go ahead without any information.

It will not start at all, he said it worked in the spring and they didn't try to do anything after that, just purchased a new one. Its a craftsman 6.25 HP Model # 917.379200

So this is where I am at:

I replaced the air filter and spark plug (which looked like they were originals), dumped out the gas and put in new. The oil looks like it has a little life left.

The cord seems to pull and recoil normally and the blade is movable when the handle is pushed down. The primer bulb feel like its pushing gas.

the problem is most of the forums I have looked at the mower will at least start for a couple of seconds, this will not turn over at all. If I try to start it several times, I do smell gas.

Any ideas where to go from here? I don't mind ripping it apart since I have no investment in it, but don't want to put a ton of money in it. I haven't worked with small engines much, but if I have good directions I can typically figure things out (so keep the language simple .

Thanks!
~Farm girl living in the suburban seas of Houston.

 

Hello Treearch03,

Welcome to doityourself.com!

In light of the things you've already done, I would start by taking the spark plug out and check for spark. Connect the plug to the wire, rest the plug so that it is touching metal on the engine, and have someone crank the engine while you watch the electrode of the spark plug so you can see if it is sparking. Be careful to do this outside and not stand in front of the spark plug hole just in case it is flooding with gas. (if it is, gas could blow out the hole and be ignited by the sparking plug and cause a big "whoosh" flame). Pull it a time or two first, then bend down to look at the plug for spark.

 

No spark from spark plug when grounded.

 

If you remove the shroud and remove the ground wire from the armature, then check for spark again, if none then it is likely the armature/coil has gone south...

Reference #333 http://www.searspartsdirect.com/part...&prst=&shdMod=

 

Take a look at the cable that connects to the flip bar on the handlebar that you hold before starting the engine. See where it connects at the engine, and watch it move when you pull the bar down. Now hold the bar down and reach down and see if you can help the moving lever move a bit more in the direction it goes when you pull the bar down. Then check for spark with it held in this position.

 

If I suspect there isn't any spark, I will always bite the bullet and hold one hand on the spark plug wire while pulling the cord with the other. There's no mistaking if it has spark or not at that point.

If he hit something with the mower, it could have sheared the flywheel key (timing key). Flywheel isn't easy for an amateur to get off. But you might be able to look at the keyway and see if it lines up. You need to expose the flywheel by taking off the shroud. Then look to see that the slot in the crankshaft lines up with the slot in the flywheel. if it does, the key is probably fine.

If this mower is old enough to have points and condenser, that's probably what's wrong w/ it. They are under the flywheel.

You could also check the throttle cable to make sure it's working properly. When the throttle goes to OFF, it trips a ground switch. If the throttle control doesn't move off of your ground, you won't have spark. But that would be an odd thing to have happen.

 

Please don't take this the wrong way XSleeper, but for the sake of proper diagnosis: This doesn't have a throttle cable, throttle controlled kill switch, or points and condenser, and if the flywheel key was sheared, it would still spark.

It's also possible to get shocked by holding a plug wire and still not get a spark, so it's not a definite way of testing and isn't very pleasant either, lol.

 

NP Cheese. I'm just thinking of the old mowers I used to work on. And ur right about the timing key... I guess I forgot it would still spark, just not at the right time!

I will stick with carpentry. LOL

 

Thanks all,
That should give me a good todo list over the weekend. I'll let you know how it goes.

 

Its up and running! I started tearing it down and the only thing I could find was the ground wire was disconnected, which shouldn't make a difference, but I vacummed out everthing and put it back together and it fired up on the first pull. one last question, The only problem I see right now is when you release the handle bar it does not shut off. The blade stops but it takes a minute to for the engine to kill. If I pull on the cable pretty hard it will shut off.

 

Sounds like you might have a cable issue as cheese was refering to.

 

And don't let it fool you...as long as the engine is running, the blade is turning. Don't put your hand under there thinking it has stopped.