Crack in engine?

[bondomerchant]

Re: Crack in engine?

that sux well looks like ya get ta fix it proper after all

 

[RandyJ]

Re: Crack in engine?

hmmm.... water could be coming in if the crack extends across the top of the block or it could be coming through a cracked head. One other source is the exhaust manifold could be leaking and running back in on top of the pistons (I've had that happen on three mercruiser engines).

 

[vampirefish]

Re: Crack in engine?

Do you think I should change the oil and run it again... or would that be a waste of time...?

 

[bondomerchant]

Re: Crack in engine?

why waste fresh oilwhere ya at over here fish

 

[vampirefish]

Re: Crack in engine?

why waste fresh oilwhere ya at over here fish

Oh, I've been reading on this forum that if you have fixed the intrusion area (like I think I did), you can try to get the water out of the oil with an oil change (or 2) to see for sure...

 

[bondomerchant]

Re: Crack in engine?

Oh, I've been reading on this forum that if you have fixed the intrusion area (like I think I did), you can try to get the water out of the oil with an oil change (or 2) to see for sure...

ya but ya thought ya had it only on the outside of the block she will just milk up again

 

[vampirefish]

Re: Crack in engine?

hmmm.... water could be coming in if the crack extends across the top of the block or it could be coming through a cracked head. One other source is the exhaust manifold could be leaking and running back in on top of the pistons (I've had that happen on three mercruiser engines).

I just went out and started it again with the oil cap off... could see the milky oil there and while it was running I saw water pour into the area... Per this bulletin:
http://www.boatfix.com/merc/Bullet/01/01_13.pdf

Am I troubleshooting that the water is at the pistons now?

 

[vampirefish]

Re: Crack in engine?

Ok... should I at a minimum drain the oil to try to prevent anymore damage? I realize this thing needs to be fixed/replaced... but if I can save any parts to it...

Anything more I can do after draining the oil? Seems there would still be water in areas that shouldn't be...

 

[RandyJ]

Re: Crack in engine?

Someone else may have more to advise than I do but at a minimum I'd definitely drain the oil and maybe even refill it and turn it over several times to put dry oil in the engine if you plan to wait a while before working on the engine.
As for the tech info I can only relate my own experience. Two boats I have with Chevy 350 engines had the same problem as also did a 140 Mercruiser. The exhaust manifolds were cracked. When first cranked they ran fine and did great. I parked the boat then went out to start and the motor was very hard to turn but I may have been able to get it to turn over not know any better. The water would be forced by the piston and rings and go to the oil pan... until I got educated enough to realize what was happening I was pulling out spark plugs to unload the water then the motor would crank and run good until shut off and parked again. In the end I had to do a complete rebuild on the 140, new cam, new crankshaft, new head and manifold..... wholesale on parts alone was over $400 for that one engine... that was about 5 years ago.

 

[Icefire55]

Re: Crack in engine?

the problem is water enter your block when you run it. puting fresh oil after 3-4 oil change (believe me, you'll need maybe more to remove the milk).

You need to find exactly where water enter and stop the leak, than oil the inside real good (fresh oil).

But as you got a cracked block already, I would just remove the motor from the boat and rebuild it. if the crack is not only exterior but also interior, you'll will waste you time trying to chase you tail and probably seize the motor.

 

[180shabah]

Re: Crack in engine?

CRAP, CRAP, CRAP! No more water running out of the cracks, but after it ran to temp... I checked the oil and it's milky as can be. Does this mean I should not drive it again? May seem like a dumb question... but I thought I'd throw it out there.

That engine is history - run it all you want, it will still be trash. Just don't expect it to run more than a few minutes before it siezes.

One other source is the exhaust manifold could be leaking and running back in on top of the pistons (I've had that happen on three mercruiser engines).

This causes hydrolock after shutdown. He stated that he could see water "pouring in" while the engine was running - it is NOT from a manifold. Although his manifolds are probably history also.

But as you got a cracked block already, I would just remove the motor from the boat and rebuild it...

This block is trash - nothing to rebuild. Only option at this point is REPLACEMENT.

 

[ENSIGN]

Re: Crack in engine?

You're just beating a dead horse! Stop wasting your money on JB weld,bite the bullet and get a reman long block.

 

[Mariah218]

Re: Crack in engine?

Sorry to hear about your freeze damage, this winter got me too, and I like you always winterise.

Since my freeze damage blew out an 8 inch square lump out of the side, there was no option other to replace the block. I purchased a block in the UK via a company called Repower Marine as it was the only company who get hold of marine blocks from the US. At least you have a good selection in the US, and I have heard good things about Michigan Motorz (others may also recommend other suppliers).

Mine was a 305 and I went with the 350 replacement option. So far, its taken me only about 5 hours to put all my ancillaries onto a 'partial engine' and its a good chance to get your ancillaries off, give them a good clean, paint and replace as necessary. Although its the biggest thing you will have bought since the boat, once its done you will be glad you went with the replacement, particularly with the extra torque of the 5.7L.

Good luck and I think you know what you have to do next!

 

[vampirefish]

Re: Crack in engine?

Thanks everyone... yeah, I'm looking into a new engine now. Looks like my summer's shot cuz I don't have that kind of cash right now. oh well

 

[vampirefish]

Re: Crack in engine?

new thread -- wanna swap out with 305 chevy: http://forums.iboats.com/showthread.php?t=424498

 

[RogersJetboat454]

Re: Crack in engine?

See new thread..