Craftsman 917.370950 Not Shutting Down when Throttle in STOP Position

[NathanF]

Hello All,
I have a 2+ year old Craftsman 917.370950 mower with Honda engine that won't turn off properly. It's one of the newer models which has a safety lever that disengages the blade rather than shutting down the mower. Instead, the throttle has a "STOP" position, which is supposed to kill it. Putting the throttle in this position slows it down a bit but it keeps on running strong. The only way I can turn it off is to put it in STOP then engage the blade / drive simultaneously to finally kill it.

I'm embarrassed to say this started while it was under warranty, possibly even from the factory or not too long after. I should have dealt with it then but didn't. It just wasn't such a huge inconvenience that I was interested in dragging the whole thing back to Sears. In retrospect, this was a stupid decision. :mur: Anyway, unrelated to all of the above, the drive cable snapped. I've got one on order, and I figure while I'm replacing it, I should tackle this issue as well.

Any thoughts? Thanks in advance!

 

[robert@honda]

Hello All,
I have a 2+ year old Craftsman 917.370950 mower with Honda engine that won't turn off properly.

The throttle lever should, when moved to the STOP position, move a cable to activate a small switch down on the engine that grounds the ignition coil, causing the engine to shut down. Inspect the cable and adjust as needed so the switch is properly activated. It is possible the switch has failed or is disconnected, so confirm it is operating okay.

 

[NathanF]

The throttle lever should, when moved to the STOP position, move a cable to activate a small switch down on the engine that grounds the ignition coil, causing the engine to shut down. Inspect the cable and adjust as needed so the switch is properly activated. It is possible the switch has failed or is disconnected, so confirm it is operating okay.

Thanks so much for the info! I was able to locate the switch, and it looks fine. The throttle itself is sticky, however. When you put it to STOP, the cable goes a bit loose, and the throttle does not close all the way. However, you can easily push it the last 1/4 inch though by hand and it kills the motor right away like it's supposed to.

It doesn't look like there are any adjustments. I tried cleaning it out as best I could, and also put a bit of WD-40 on the spot where it pivots, but it still is rough closing on that last little bit. I might just leave it as is, since at least now I know all I need to do is reach down and push the throttle closed all the way to shut it off.

Thanks again for the help.

 

[hrdman2luv]

Thanks so much for the info! I was able to locate the switch, and it looks fine. The throttle itself is sticky, however. When you put it to STOP, the cable goes a bit loose, and the throttle does not close all the way. However, you can easily push it the last 1/4 inch though by hand and it kills the motor right away like it's supposed to.

It doesn't look like there are any adjustments. I tried cleaning it out as best I could, and also put a bit of WD-40 on the spot where it pivots, but it still is rough closing on that last little bit. I might just leave it as is, since at least now I know all I need to do is reach down and push the throttle closed all the way to shut it off.

Thanks again for the help.

That last 1/4" is where the lever needs to be when in the stop position. Adjust it to that point.

 

[mechanic mark]

CRAFTSMAN MOWER Parts | Model 917370950 | SearsPartsDirect information your mower

 

[NathanF]

That last 1/4" is where the lever needs to be when in the stop position. Adjust it to that point.

When you say adjust, could you elaborate? I didn't see any places to make any adjustments. It seems like there is something physically impeding the smooth closing of the throttle, rather than the throttle cable not allowing enough travel for it to close. When I put the throttle lever to stop, the cable has a bit of slack in it, and all it takes is my finger to push the throttle closed all the way down at the engine. When I do that, I can feel that there is some resistance or roughness to the last part of it. The return string is just not strong enough to overcome whatever is making it bind.

I fear at this point I may just have to take it in somewhere, or just live with it. :mur: At least now I know I can just reach down and push the throttle shut rather than lugging it to death to turn it off. Thanks again for the advice and info.

 

[robert@honda]

On this Honda engine, the stop switch is controlled by the throttle. It is a plunger-style, the switch has two contacts, one to ground, one to the ignition coil, and they are normally OPEN (not connected).

When the throttle is moved to STOP, the plunger is pressed in, the contacts are closed, the ignition is grounded, and the engine stops. If it does not, either the switch is defective, or there is some mechanical slop/failure between the switch and the throttle lever.