What does backfire while spinning over mean?

[snake91876]

Im trying to get my 48hp evirude running again and checked everything to the carbs , have fuel in bowls, sprayed fuel in carbs and get a backfire then while spinning , what is causing this . the backfire is out exhaust at foot.

 

[rockyrude]

Re: What does backfire while spinning over mean?

Back firing of any kind means the timing is off, check the sticky for Joe Reeves timing procedure. It's in the top secret file.

 

[JB]

Re: What does backfire while spinning over mean?

The easy to fix backfire cause is plug wires on the wrong plugs of a twin.

A bit harder to fix is a sheared flywheel key.

 

[snake91876]

Re: What does backfire while spinning over mean?

JB how can i tell if the flywheel key is sheared i took the nut off but thats all i did. I know the plug wires are right and i pulled carbs and looked at reeds they are fine.

 

[mikesea]

Re: What does backfire while spinning over mean?

pull the flywheel and visually look at the key in the crank,it will be obvious,your plug wires may be right,but are the smaller wires correct to the coils

 

[petryshyn]

Re: What does backfire while spinning over mean?

http://forums.iboats.com/showthread.php?t=355953

 

[snake91876]

Re: What does backfire while spinning over mean?

Flywheel key is sheared, will install new one and hope for the best , shaft is a little gouded up but the keyway looks good.