# Need help.. 1985 Mercruiser 140/3.0L



## Crazy Axe (Mar 11, 2007)

I've got water in the oil and I think the head gasket is blown but not 100% positive. The boat was left outside since last spring or the summer before idk and the drain got all clogged and filled the engine compartment with water. My buddy swears that, if part of the motor is submerged, that water can get in and contaminate the oil that way... I don't quite understand that, but that's why I'm asking here. Is it given that if there is water in the oil, that the head gasket is toast or is it really possible that water could have gotten in through "osmosis"? :lol:

Also, I can't get it to turn over but I think it's because the lower end of the motor is so filled with oil/water that it just can't crank it. I'm really hoping its not seized, and that pumping some of that will allow it to turn over. I should be able to spin the motor by hand from the crank pulley, right? (not easily, of course)

ALSO, I am trying to track down a shop manual for the ENGINE. I seem to have found one for the outdrive, but not the actual motor. If I can salvage this thing, and have to change the head gasket, I'm going to need a torque pattern and amount. Also I would like to do some reading on the carb as I think (from when the boat was running) that the accelerator pump might not be working and/or the carb needs adjustment 

Any info is MUCH appreciated :coolgleam


----------



## Crazy Axe (Mar 11, 2007)

I've read a few things about cracked manifolds causing this problem as well. I assume its the intake? How do I know for sure WHAT needs replacing? I know it's going to need SOME taking apart.. Will I be able to see the culprit crack? What if the head or block is cracked? How can I know for sure?


----------



## Quack Addict (Aug 10, 2006)

I have seen water get into the crankcase of an engine that was partially submerged. I think the water gets past the rear main seal or the lip seal in the timing chain cover. The lip seals are meant to keep oil IN... a little water pressure from the wrong side of the seal can push past easily without damaging the seal...

I'd drain the oil pan as much as possible. Change the oil filter. Install fresh oil. Take the spark plugs out and spray a fair amount of penetrating oil or even WD-40 in every hole. Break the crank free with a 5/8" socket on the front of the crank shaft. Once it's broken free and turning over by hand, spin it up with the starter (without spark plugs installed). Once you have it spinning over nice on the starter without spark plugs, reinstall the spark plugs and start it up.

There's also a possibility rain water got in the oil somehow from above. Coud have puddled up somewhere and bypassed the valve cover gasket or something. 

If the head gasket is bad you mght be able to see it with a compression test on the engine but the best way would be a leak-down test.

If the block is cracked internally, you might not be able to tell without disassembling the engine. Same with a cacked head. The only way you'd see a craked block or head on a compression or leak-down test would be if the crack was allowing water into the cylinders.

Most issues are simpler than your OMG first impression / worst case scenario. 

If the block or head is cracked, with fresh oil in it, you will see the oil level going up due to water displacement after some run-time. If you don't see the oil level going up, the water probably came in through a seal as I described earlier.

Good luck.


----------



## Crazy Axe (Mar 11, 2007)

Thanks much! That's pretty much the info I was looking for. I am worried because he's not giving me a straight answer to the question "Did you winterize it last year or did you have someone do it?" he "might have done it" and when I asked him how, he said "poured antifreeze into the coolant line" and didn't know anything about the water drain(s) on the motor.

I saw a cool rig on youtube this guy used a brewing bucket, like a 5 gal, with a tap on the bottom of it. Rigged it to a garden hose and to his earmuffs, filled the bucket and ran the engine. It drew all that antifreeze into the motor nice.
Seems like you'd have to do this with the engine warm, so that it gets past the t-stat too? Idk, I/Os are pretty new to me.


----------



## Quack Addict (Aug 10, 2006)

There are freeze plugs on the side of the engine block but they often rust in place and don't push out when an engine freezes. 

Winterizing an engine by sucking antifreeze up through the drive will leave you with expensive problems at some point. 

The last boat that I bought had a bad engine (= deal for me!). Previous owner didn't winterize it properly and both sides of the engine block blew out with pieces of casting laying in the bilge. There was some antifreeze in the block so I know someone tried to winterize it but obviously didn't do it right. It's important to follow the proper procedure!

I have seen a lot more cracked exhaust manifolds than cracked engines. A cracked exhaust manifold is a good indication of how well an engine was maintained. You often see manifolds that were brazed or JB Welded... sometimes just whitish drip marks from water seeping and running down. If you see any of that there's a fair chance the block may be cracked inside or out. 


Outdoor Hub mobile, the outdoor information engine


----------



## Crazy Axe (Mar 11, 2007)

I got it moved a little bit. Had to take the motor mount off (I used a ratchet strap to hold the motor up from the removal bracket) and there was 3 bolt holes in the balancer. Ran to HoDepot and picked up some bolts that fit it, threaded them, and put a pipe in there. We got it to break loose and moved it about an inch either way. Then I sprayed more WD in it, put the plugs back in, and I'm gonna let it sit. Going to do the same thing tomorrow and Tuesday, then Wednesday I'm going to start turning it about a half a turn for a couple of days, and then next weekend I'm going to try to crank it over.

I read a few other things, about people with similar problems with "seized" motors and the advice was always the same. Be gentle, be patient, use penetrating lube or similar, and you will save what you thought was lost.

Thanks a million Quack!


----------

