1969 Mercury 50 hp

['57Lapline]

I just got a boat with a 50 hp merc on it and the guy said the motor is junk. But I dOnt think that it is because it starts and everything. He said it just wOnt go very fast only a few mph. He also said the water pump doesn't work. So I have no idea how to diagnose what may be wrong. Please help

 

[JB]

Re: 1969 Mercury 50 hp

First: Replace the impeller.

Second: Do a compression check as instructed in the Engine FAQs Forum.

Third: If compression checks out you are probably dropping at least one cylinder. Start her up and at idle pull (with insulated pliers) one spark plug wire at a time. If there is no effect that cylinder is dead. If idle drops or the engine dies, that cylinder is making power.

Let us know what you find and we can take it from there.

 

['57Lapline]

Re: 1969 Mercury 50 hp

Alright I'll do that.