[Rikki Sixx]

The 17.5 engine on my rider will not rstay running whr the throttle is in the lowest position. Also, when I place thr throttle to full speed, the engine pulses low and high. What could cause this?

I've clean the plug, air cleaner and adjusted the magneto gap. Still no change.

 

[Mark / Ohio]

What make is the engine? Briggs?

Tried a fuel filter? My guess would be an air/fuel mixture problem of some sort. I'm also guessing that carb is probably not adjustable?

 

[Brad]

In addition to what Mark/Ohio suggests, I would recommend a shot of fuel line cleaner. Sea Foam is a great product that will really get your carburetor clean. On an engine such as yours I would suggest about a 1/4 cup of cleaner to a 1/4 gallon of fuel, just for a real good deep cleaning. Put it in, run the machine for a while to get the product circulated, the pour a bit more into the carb to flood the engine out. Then let it sit for about a half hour. When you re-start it, it's going to smoke pretty good, but your problem should slowly disappear, as will the smoke.

Keep us informed.

 

[Mark / Ohio]

One thing I forgot to mention that bit me in the behind again only about a month ago is the vent on the fuel cap being plugged. Just loosen or pull the cap with it running and see if the idle comes back and the high end smooths out.

I found that to be the issue with my MTD push mower after I had pulled and cleaned the carb trying to solve it. Oh well, 20 years since I last pulled the carb on it so it was probably due for a cleaning anyway.

My old Jake rider had the vent plug on it once but it would just run out of fuel in about 15 minutes and stall.

 

[Ernman]

One thing I forgot to mention that bit me in the behind again only about a month ago is the vent on the fuel cap being plugged. Just loosen or pull the cap with it running and see if the idle comes back and the high end smooths out.

I found that to be the issue with my MTD push mower after I had pulled and cleaned the carb trying to solve it. Oh well, 20 years since I last pulled the carb on it so it was probably due for a cleaning anyway.

My old Jake rider had the vent plug on it once but it would just run out of fuel in about 15 minutes and stall.

Thanks, Mark / Ohio. Your hint about the gas cap vent being clogged was right on. I had done all the usual checks and cleans, etc. to my 17HP Kohler Craftsman rider to no avail. I was stumped. It would run perfect for a few minutes and then choke down. Cleaning the gas cap vent did the trick. Thanks again for coming back and posting that follow up comment when you were helping Rikki Sixx back in September. Rick.

 

[Brad]

Hey, glad that Marks suggestion was right on target for you, Ernman. Hope you enjoy visiting our site upon occasion. Thanks for sharing your results.

 

[Mark / Ohio]

Thanks, Mark / Ohio. Your hint about the gas cap vent being clogged was right on. I had done all the usual checks and cleans, etc. to my 17HP Kohler Craftsman rider to no avail. I was stumped. It would run perfect for a few minutes and then choke down. Cleaning the gas cap vent did the trick. Thanks again for coming back and posting that follow up comment when you were helping Rikki Sixx back in September. Rick.

Welcome to the forum Rick and thanks for letting me know that helped get you running again!