4.3 mercruiser on 1996 glastron

[alldodge]

Reading back thru the thread the motor has water in the cylinders. All water in the block was drained, motor cranked until no water comes out of cylinders. Tried to start and no good and a backfire

Need a compression test to see if something is bent

 

[Rick Stephens]

Could have crossed up spark plug wires while cranking the water out. That’ll cause a backfire too.

 

[cobalt1999]

After letting the boat sit for a week because it was raining, the boat started up first try. Only ran it for about 15 seconds because I did not have it hooked up to water.

I may be wrong but you may need a new water pump now.