1989 OMC help please

[tpsball]

ok, heres what i did so far, new starter ,new belts, just replaced both head gaskets,manifold gaskets,and intake gasket. marina says after all work done might have possible crack in head, motor runs great with muffs,but when in water still would overheat and lose power in gear. Does this sound like a cracked head or something else? thanks

 

[SS MAYFLOAT]

Re: 1989 OMC help please

Have you checked your water pump impeller? Being on muffs, the well/city water pressure can push water on through your engine as if your pump is okay when it is possible that it is bad.

 

[jriegle04]

Re: 1989 OMC help please

when was the last time it got a new impeller?

 

[tpsball]

Re: 1989 OMC help please

never gave that a thought!!! thanks, will try that

 

[tpsball]

Re: 1989 OMC help please

I can get a hold of a 3.8L v6 200HP, more than my 4.3, must have a 4 bbl carb. my question is, is that the same set up as the 4.3l? it should be the same size externially right? compatable? anybody know? thanks

 

[jriegle04]

Re: 1989 OMC help please

not to sure on that but either way if you are using the same lower end you will have to change the impeller. it is in the lower end...

 

[danond]

Re: 1989 OMC help please

Have you CHECKED THE IMPELLER? Not sure if you saw the previous posts directing you there....

 

[Rat Capri]

Re: 1989 OMC help please

I can get a hold of a 3.8L v6 200HP, more than my 4.3, must have a 4 bbl carb. my question is, is that the same set up as the 4.3l? it should be the same size externially right? compatable? anybody know? thanks

3.8 is not configured the same as a 4.3, would have to redo motor mounts (in the boat) would be easier to drop in a SBC V8, same mounts as a 4.3 just longer (up front)

 

[tpsball]

Re: 1989 OMC help please

thanks guys, gunna change the impeller right now! thanks

 

[tpsball]

Re: 1989 OMC help please

While waiting to get my impeller changed out I've been doing a lot of reading here and there is a lot of overheating issues that exhaust manifolds are to blame on older engines. I think i will change my exhaust manifolds as well as the impeller, both make sense with the water pressure from the muffs and the back pressure on the outdrive with the exhaust, but none with the muffs! what do you guys think?

 

[danond]

Re: 1989 OMC help please

Manifolds are a grand at their cheapest. Two grand plus for factory replacements. Make sure they're bad before you replace them.

 

[Gary H NC]

Re: 1989 OMC help please

Complete 4.3 Cobra manifold kit at ebasicpower for 699....
Includes all new bolts,gaskets,risers and exhaust boots.
Get the impeller changed first.....30 minute job...

 

[tpsball]

Re: 1989 OMC help please

The impeller is being changed as we write..... I have an extra set of manifolds, one being welded now and i know they are clean inside, i will swap them out as well.

 

[tpsball]

Re: 1989 OMC help please

still waiting on the outdrive, i left the boat outside while i ran to do an errand and we got a bad thunder storm and rained down the carb, how much i don't know. So, I pulled the plugs and bumped the motor to blow any water out. A considerable ammount came out the port side and none from the stbd side. I squirted some oil in each cylinder for safety. Now, this port side is the side one mechanic(the same one who put new head gaskets on) said the head was cracked, so, i did a compression check, every cylinder was reading 120 except the middle one port side and it was 90. water in cylinder, low compression, could it be a cracked head?? thanks, and sorry so long!