The engine has been running great and yesterday it just died for no apparent reason. I played around with it today and this is what seems to be happening.

It will run pretty well at slow idle. As soon as I throttle it up the governor yanks the throttle plate open and it stumbles and gasps before finally reaching fast idle. It will generally fast idle for just a moment before the governor begins to open the throttle plate again. The downward spiral begins as the rpms fall and the throttle plate accelerates it's opening up until the engine quickly dies. Sometimes I can return the throttle lever to slow idle fast enough to keep it running but usually it dies too fast.

Any ideas would be appreciated- thanks.

It sounds like a fuel issue or perhaps a restriction in the carburetor. Possibly there may be some water in your fuel that is made it's way into the carburetor, or some foreign material has gotten in the main jet and is not letting enough fuel through.

If you can post the model type and code number off of your engine, we can give you some ideas of how to proceed to investigate your issue.

Thanks for the reply. From the engine plate:

Briggs and Stratton
Model: 422707
Type: 1510 01
Code: 90091332

So what's happening is that the throttle plate should be opening as it is but there's not enough fuel being delivered to sustain it?

Thanks again.

Check out this thread, it's not the exact same model as yours but the carburetor is pretty much the same and this should explain what you need to do to check out your carburetor.

http://www.hobbytalk.com/bbs1/showthread.php?t=112289&page=2

Read the posts by Restrorob as they have the information you need. Be sure to Ignore the posts by Nitrojc as they are not pertinent at all. The illustrations in Restrorob posts are great, I would start by removing the plug that allows access to the high speed jet (#117B in illustration), fuel from the bowl will flow out. Pay special attention to what comes out, if there is any water or a large amount of dirt, build up etc.. If it's clean and no water, then examine the jet, I have seen small blades of grass plugging them up before.

Post back with your findings.... and best of luck.... :thumbsup:

Thanks, I've been out of town and will let you know what I find out this weekend.