View Full Version : FC150V Starts but loses power

07-18-2012, 11:02 PM
I have a Snapper 21" Comm. self-prop. with the above engine. I soaked the carb in carburetor cleaner, put in new needle, float and gaskets. Fresh fuel. Good oil level. Good gravity flow from the fuel tank. Starts great, idles great, mows great for about 50' then loses power. Almost dies, runs rough. If I try to keep mowing, it dies immediately. No longer idles smoothly. Then its hard to start. If I let it cool a few hours, it starts up great again. Any ideas what might cause this?

Thanks in advance.

07-19-2012, 11:20 AM
Sounds to me, I know you don't want to hear it, but it's probably the carburetor.

10-02-2012, 10:56 PM
Thanks MS_SURVEYOR for your response. I disassembled, soaked, cleaned, checked the carb. Still seems great. Great flow from fuel tank through the bowl drain. It starts and runs until the engine has been loaded for about a minute. Then it loses power and slows down. If I continue mowing, it dies. I noticed the governor external linkage was dirty so I tweaked it back and forth. I was able to duplicate the poor running condition. Then I sprayed the external linkage with carb cleaner followed by silicone. Unfortunately, I got no improvement. The external governor linkage sure looks better though. <gr>

Anyway, I am unsure what adjustments or parts in the governor system might be related to engine temp. Also, what serviceable parts might I check? Is there a ready adjustment? What about the governor spring attached to the throttle butterfly? Could that be stretched / damaged when I removed / replaced the carb?

Thanks in advance for any suggestions.

10-09-2012, 10:06 PM
I decided some expenditure was in order, so I bought a new coil from Partstree. With help from this site, I installed the coil and adjusted the flywheel clearance. Voila'. It always started and it still does. Now, though, it runs strong and no miss or backfire.

My thanks to everyone whose posts helped me figure this out. I would still be scratching my head and dithering over a $100 coil.

Darryl G
10-09-2012, 10:17 PM
My dad had a mower that used to do that. He used to just kick it down the basement stairs to his workshop and then it would run fine. Might wanna try that next time.