another water in oil problem

[james67]

1985 4.3 mercruiser, i got boat used been working on it and found my oil level was high drianed some out and found the water , presure tested exhaust manifolds, and replaced the rizors. prior to this i took head off and someone has tooken it apart before. anyway i replaced all gaskets put it back together, run on hose for 20 min. full of water ! took it back apart valley has alot of water in it and dis. shaft is soaked. i looked for cracks can not see any. whats my next move ?

 

[HT32BSX115]

Re: another water in oil problem

Howdy,


You should pressure check the block/heads/intake-manifold before taking anything apart.

Using air pressure will allow you to identify where the leak(s) is/are

It should easily hold 15 psi or so. remove the valve covers and spark plugs. You can use a piece of vinyl tubing as a sort of "stethoscope" to listen.

It sounds like you have either a cracked block or leaking intake manifold.

The GMC small block engines like to crack the water jacket right next to the pushrods when the water in them freezes.

Regards,


Rick

 

[Gary H NC]

Re: another water in oil problem

Agree with Rick,
Sounds like a new block may be in your future....bummer...

 

[james67]

Re: another water in oil problem

i did a presure test on block , i how ever did not take plugs or covers off, held 20 psi all day. i looked at valley again do not see anything. i striped head down taking it to shop if its good , will start looking for short block. it would make me feel better to know for sure,would suck to go through all that and have same problem.

 

[Bondo]

Re: another water in oil problem

anyway i replaced all gaskets put it back together, run on hose for 20 min. full of water ! took it back apart valley has alot of water in it and dis. shaft is soaked. i looked for cracks can not see any.

i did a presure test on block , i how ever did not take plugs or covers off, held 20 psi all day.

Ayuh,... Tell Us, Exactly, how ya pressure tested it....

If it filled the motor with water from 20 minutes on the hose,...
Holdin' air shouldn't happen....

 

[james67]

Re: another water in oil problem

i pluged all the water hoses and i took one off out drive down by coupler , made a fitting with gauge and tire stem put air to it. someone told me that it might not leak until hot . also guy i bought boat from confessed that water pump went and he nursed it back to dock, so it probly got really hot. taking head in monday let you all know.

 

[james67]

Re: another water in oil problem

hey i almost forgot the exhast manifold test i done was by making a plate for top where rizer is and hooked garden hose to it , is that good or should i put air to it .

 

[james67]

Re: another water in oil problem

just got back from shop the head was badly warped, he is going to mill it down.

 

[Bluestream]

Re: another water in oil problem

Would a badly warped head cause low compression readings?

 

[Bluestream]

Re: another water in oil problem

ttt