89 2.3 OMC issues

[dawson515]

I have an 89 2.3 OMC. I have been having problems with a small rattle noise coming from the engine. The engine will idle fine but when start giving it gas it starts making a small knocking noise. This only happens while the boat is in the water. When you run it on the muffs you can not hear any rattle or knocking noise at all. Also the boat smokes some while it is out of the water running on muffs. There was a previous overheating issue and I am wondering if this caused any of the damage. Is this a possible blown head gasket??? Thanks for any info.

 

[Bondo]

Re: 89 2.3 OMC issues

Ayuh,... The knockin' noise is probably detonation...
the Smoke,..?? what color,..?? Do a compression,+ leak-down test...

 

[dawson515]

Re: 89 2.3 OMC issues

The smoke is white.

 

[dawson515]

Re: 89 2.3 OMC issues

Would there be a reason why you dont hear the knocking sound while the boat is out of the water running on muffs, but only while the boat is in the water?

 

[ssoder]

Re: 89 2.3 OMC issues

Dawson515, I'm curious if you have figured out your issue? I have an 88 2.3 OMC and I'm experiencing the same issue. I first thought it might have been the U-Joint needing to be replaced but I inspected it and it looks fine. Mine also sounds and runs fine with the muffs but when its in the water the knocking sound is very noticeable. I'm pretty confident my issue is in the outdrive somewhere and not in the engine. I have inspected my gears and they look good, I'm thinking lower unit. If you have fixed yours can you let me know what the issue was?

Thanks!

 

[Bondo]

Re: 89 2.3 OMC issues

I first thought it might have been the U-Joint needing to be replaced but I inspected it and it looks fine.

Ayuh,.... If you didn't take 'em Completely apart, they Haven't been "Inspected"....

 

[dawson515]

Re: 89 2.3 OMC issues

I did find out the problem and I fixed it on Friday evening. The head gasket had blown. I went to O'reilly's and bought a new one for ten bucks tore the engine apart replaced the head gasket and the intake and exhaust mainfold gaskets and the valve cover gasket and it runs great now.

 

[ssoder]

Re: 89 2.3 OMC issues

Thanks for letting me know. I pulled my outdrive and brought it to a local repair shop to inspect the gears in the lower unit (I just don't have time to work on it right now). If they are good then I may take a good look at the engine after hearing the gaskets took care of your issue.

Thanks again!

 

[dawson515]

Re: 89 2.3 OMC issues

Just run a compression check on all four cylinders. That will at least tell you if you have a blown head gasket. Here are a few things that I noticed. White smoke coming from exhaust, more than just steam. Boat would not idle properly, knocking coming from engine. That 2.3 is pretty easy to work on. I am by far no mechanic, but I was able to change the head gasket myself. Hope this info is helpful to you.