I need spark plug gap for a crafstman mower model # 917387680?

https://www.briggsandstratton.ca/na/en_ca/support/faqs/browse/identifying-the-correct-spark-plug-and-gap.html

Champion rc12yc and the gap is dependant on the motor. The motor number is needed.

Hi
If you enter your model number (and serial number if you have it) at the link below, you'll have access to your owner's manual which will tell you what your spark plug gap should be.
Hope this helps.
-Steve


Operators Manual

You didn't mention what brand or model engine you have, but most engines in that horsepower range use a gap of 0.030 inch. You can find many spark plug gap specs by engine model at http://outdoorpowerinfo.com/engine_specs/ .

Generally the spark plugs for mowers come pre-gapped. I use to measure but they were spot on, so now I just do eyeball comparison from the old to the new one, just to check.

Check your key way. Might be cut or broke in half. Its the timing of the engine.

The two most likely suspects for the symptom you describe are:
a) Ignition coil failure under high heat.
OR
b) Decompression failure due to normal wear.

For a positive diagnosis try the following:

For scenario a)
Run the engine until it shuts itself down. As quickly as possible, check for spark using a spark tester (availabe at local auto parts store). If no spark when hot, allow to cool down and test again. If good spark when cold and no spark when hot, change the ignition coil.
Proper part number (assuming your machine is still all original) Briggs & Stratton part #492341.

For scenario b)
Run the engine until it shuts itself down. Try to restart but pay close attention to the speed of the spinning starter. Next, remove the spark plug and spin the engine over (WITH SPARK PLUG WIRE WELL OUT OF THE WAY!!) If the engine spins super fast and free you can discount the theory of a bad battery and you will need to adjust the valve lash.

Determine which is the case and reply to this post. I will gladly give a detailed explanation of the valve lash adjustment procedure in another post.

Hope this helps!

sounds like your coil is getting hot and shutting down,, cool off and run for a while more,, coil is located next to the fly wheel,, just follow your spark plug wire and you find it,,,good luck

sounds like your coil went bad

The spark plug gap is .030.