742B dies after 20 minutes

[Bobcat742]

742B gas. Starts runs great for 20 minutes and dies. After it cools down I can startit and it runs great until it heats up then it spuyters and dies. It has an electric fuel pump which I can hear humming when I turn on the ignition but until it cools down it won't start.
Any suggestions would be greatly appreciated.

 

[Scott Cee]

I'd try mounting the pump elsewhere. They have no fuel return line so they're at higher risk of vapour lock. You could get a return regulator and add one in, but that seems excessive.

 

[bbauman]

Mine had a fuel shutoff solenoid inline about an arm's length deep that caused the exact same problem. Try bypassing the solenoid temporarily to see if that is your issue. Replacement solenoids are inexpensive on eBay/amazon.

 

[flat sk]

Check your ignition coil. Coils often fail like that, work well when cold and no spark after warming up.
I had the same symptoms with mine. Was thinking vapour lock/carb issues, nope.
I had a Petronix coil and ignition on the shelf that I was procrastinating putting in. Installed and ran as good as it ever has.
TB

 

[mrbb]

old thread, but you can also check your fuel cap and make sure its venting , as it could be getting vapor lock