Sudden loss of RPMs, need help quick

[GraAlaMat77]

I have a 92 Ranger 391 with a 92 Yamaha Pro V 200 on the back. I was out on Murray today and the motor all of a sudden dropped from 5300 rpms to 3800. I cut it off and cranked it back up and it wouldnt plane out or go about 2600. It finally got up to 3800 after sitting on 2600 for a while. i got it up to 4200 in a turn but then it settled back to 38. What went wrong, and how can i fix it, im supposed to fish a tournament saturday.

 

[rodbolt]

Re: Sudden loss of RPMs, need help quick

test compression, test spark. if they pass find your fuel issue.

 

[GraAlaMat77]

Re: Sudden loss of RPMs, need help quick

it was a blown head gasket. shes all fixed and ready to go.

 

[rodbolt]

Re: Sudden loss of RPMs, need help quick

now check for why it blew. ususally it ran on the hot side.

 

[GraAlaMat77]

Re: Sudden loss of RPMs, need help quick

it blew because of a dimple on the head. the head was resurfaced before the new gasket was put on. Fished today, gained 3000 rpm to 5600 and 4 mph. to 61.5. Can't wait to get rid of my old clunker prop and let the lead sled fly.