Briggs 5 HP hard to start when warm

#1
I have a Briggs 5 hp Fun Power engine with an older style carb that is hard to start when its warm even if you only kill it for 30 seconds... I would often start it choked with the throttle wide open! It is often easier to start when cold and runs really strong This mini bike had been sitting in my garage for a year and I just did a tune up on it (rebuilt carb, new spark plug, oil) I'm guessing its ether the ignition coil or the valves? I am mechanically inclined and have tinkered with alot of briggs engines but I have never messed with one internally so I'm not exactly sure what to do if it turns out to be the valves...

Nick
 
#5
Is this a magnetron engine? If not, that is a great upgrade, but I think the Fun Power is built with it.

A good investment is a $7 spark tester. You can remove your spark plug, hook it to the coil and yank it and see a good spark, when in actuality the spark in it's higher compression environment is not adequate. In your case, you'd only see it when hot, since that is when the trouble starts.

Another probably obvious to you, check is to try and start it when it's hot, have the issue, then pull the plug and see what it looks like. It might direct you to a fuel condition as well.

I have one that acts similar. If I screw up and try and start it when hot, but forget I have the plug still shorted with the "on/off" lever, it wont start for a very long time. Too much fuel. Never did chase it down, but I suspect a plug. (and it's a new one that's in it)
 
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