Mac .21

[rchydro]

I have been having a little trouble with the mac .21 in my sg

It runs for a few laps then stops

I popped it out of the boat and found that the fly wheel is hittttings the nose of the case and the small cone behind the fly wheel has a grove in it

Question

What is going on here, Is the nose bearing at fault

How much space is there behind the fly wheel and nose of the case

Thanks

 

[Preston_Hall]

Do you have the brass compression cone installed? If so the brass cone is what contacts the bearing and it should extend beyond the back of the flywheel.

 

[rchydro]

The cone is black ,it didnt look like brass

This is the cone this has the grove in it on the bearing side

 

[Preston_Hall]

Sounds like the cone/flywheel spun and wore a groove. But the purpose of the cone is still the same 1) to link the flywheel to the crank 2) keep the flywheel off the bearing. Either the flywheel is worn and the cone goes to far in or the groove on the cone is allowing the flywheel to contact the case and/or bearing.