88 GM 305 Carbed: Mechanic said I need a new motor?

[jigeye]

OK. Here goes. 88 Four Winns Candia 200
GM 305 Carb motor.
504APRGD model

It started to not hold rpms under a high load (8 kids/2 tubers). Ran fine when not under load. Put another fuel pump on it but did not fix. Points checked good. Mechanic now says it needs a new motor as the #3 cylinder shows 40psi.
Question: Does this make sense? Last time I took it out I noticed the boat wouldn't hold steady rpms (100-150rpm decrease/fluctuation) even without a load. Would a bad cylinder make this act this way?
It has a brand new OMC remanufactured outdrive. Works good.

 

[Bondo]

Re: 88 GM 305 Carbed: Mechanic said I need a new motor?

OK. Here goes. 88 Four Winns Candia 200
GM 305 Carb motor.
504APRGD model

It started to not hold rpms under a high load (8 kids/2 tubers). Ran fine when not under load. Put another fuel pump on it but did not fix. Points checked good. Mechanic now says it needs a new motor as the #3 cylinder shows 40psi.
Question: Does this make sense? Last time I took it out I noticed the boat wouldn't hold steady rpms (100-150rpm decrease/fluctuation) even without a load. Would a bad cylinder make this act this way?
It has a brand new OMC remanufactured outdrive. Works good.

Ayuh,.... My guess is, the root issue is Bad fuel delivery, or Bad fuel....

Ya kept runnin' it, 'n detonation set in,...
That Smoked the #3 hole, 'n/ or the piston...

At 40 psi, the head has to come off, to see how bad it is,...
After that, it can be determined if yer buyin' heads, or a new motor,...

'n Before ya drop in a new motor,....

Fix the fuel delivery issue....