merc 140 3.0, water and oil.

[DennisM]

Ok heres the story, got the boat, a 1986 four winns horizon 190, with the merc 140 in it.

Boat sat for two years, after the PO noticed it running hot and leaking water.

Once I got it, noticed it had a lot of water at one point in it, up to the flywheel cover. Noticed a crack in the block which I previously had a pic of up. |Repaired the crack, and now boat is running, not overheating, and not showing any water leaking out anywhere. Thats good I guess.

I also changed the oil as it was a very creamy coffee color. Once I drained the old out, I put a couple quarts in and just cranked it a couple times, not starting, just turning over, to move the new oil through the passages and filter.

Drained that out, refilled with new oil. Ran it today for about 10 mins total, and after trying to figure out a sputter in the carb, decided to check on the oil. Its back to being a nice creamy coffee color.

Now my questions are, did I just not get enough out of the old before and it has recontaminated the new? or could there be a crack that is only leaking into the block and not showing signs outside the block?

I am planning on draining it all again tonight, filling it, starting it and letting it idle for a few mins, then draining again, refilling and then the same and checking after that..

 

[HT32BSX115]

Re: merc 140 3.0, water and oil.

Now my questions are, did I just not get enough out of the old before and it has recontaminated the new? or could there be a crack that is only leaking into the block and not showing signs outside the block?

It's possible that you didn't get all the water out of the pan.

It's also possible that you have a cracked block. pull the lifter cover off (starboard side). You'll see the pushrods there. you may also see a rusty crack. If you don't have a leak in there it could be internal.

The best way to check will be to isolate the manifold, plug off the water openings etc, and pressurize the block with compressed air. The block should easily hold 15psi.


Regards,


Rick

 

[Bt Doctur]

Re: merc 140 3.0, water and oil.

Let it drain overnight,remove thermostat, remove hose from therm housing to manifold for now and cap/kink/close it . hook up a hose to the water inlet and turn it on.
cracked block will have water come out the drain hole

 

[Bondo]

Re: merc 140 3.0, water and oil.

or could there be a crack that is only leaking into the block and not showing signs outside the block?

Yes,.....

 

[DennisM]

Re: merc 140 3.0, water and oil.

Thanks guys, I will try BT docs method first.

Couple questions, where is the therm housing on this one and where is the water inlet hose to feed the water into?

Dennis

 

[DennisM]

Re: merc 140 3.0, water and oil.

Yes,.....

not what I wanted to hear! But when is the truth anyway right?

Arrg, already got close to 600 into it just to get this far, might as well keep going...

 

[Bt Doctur]

Re: merc 140 3.0, water and oil.

http://www.boatfix.com/merc/Servmanl/13/13covr2.pdf
6A-2

 

[DennisM]

Re: merc 140 3.0, water and oil.

Thanks, finally got that link to work right, had to use IE and not firefox...

Anyway, quick question, if I have a external or internal water leak, that is not showing on the outside of the block, and only getting into the oil, wouldn't my oil level increase each time the boat is run?

Just wondering, cause I took it for a 10 min run to warm up the oil and the level didnt change on the dipstick, right at full still..