Mercruiser outdrive question

[jakeb]

I have a 79' 470 with a mercruiser outdrive that now makes a terrible noise.
I was on the lake at about 3/4 throttle when the engine slowed suddenly and died. Tried to start it but it just cranked very slowly and never started back up. I got the boat back home and was able to fire it up but it still cranked slower than normal and feels like the engine has a load on it all the time.
There is a clunking noise coming from the outdrive (or what seems to be from the outdrive) anytime the engine is running. The boat will still go into gear but that noise is obviously a problem.

I have done a compression check and I am pretty confident that the engine is still mechanically sound. It seems like there is a croaked bearing or something causing the resistance. Before I rip into the outdrive I was hoping that there is a chance that this might be a common thing and get some direction.

Thanks guys
jake

 

[EddiePetty]

Re: Mercruiser outdrive question

....first isolate the noise by removing the out drive and briefly running the engine.

FWIW....Ed in 'ol Virginny

 

[Bt Doctur]

Re: Mercruiser outdrive question

check engine oil level
Check the oil level and condition in the drive
remove drive to isolate the noise

 

[jtybt]

Re: Mercruiser outdrive question

If you broke anything in the drive, drain a little drive oil and you'll see the results.

If that's clean, the gimbal bearing and U-joints are next.

 

[cr2k]

Re: Mercruiser outdrive question

Most likely a bearing going bad. Try greasing the gimbal thru the fitting and see if that helps. If so that is your culprit.

 

[Bondo]

Re: Mercruiser outdrive question

Ayuh,... Pull the drive,+ Fire it up,...

Is it better, or the same,..??

Atleast then you'll know whether it's the motor, or the drive...