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57L OMC Engine OverHeated Now what

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kunka85

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I have an OMC 5.7L OMC engine

I have an OMC 5.7L OMC engine which overheated while idling. After cooling down the engine failed to crank. I had a mechanic check the engine and he mentioned that water had entered the engine which was preventing it from turning. He opened the spark plugs and reported that water came out. After installing new sparks it failed to start.Does this mean the engine is shot or can you suggest other things to try. Engine has 40 hours on it.
 
That's what I've been

That's what I've been told. Can I replace a head gasket on my own or is it something best left for a professional? If I remove the heads manifold will I be able to see the cylinder head?
 
"If you've never done any

"If you've never done any engine work you might be better off hiring a pro. Head gaskets are not that difficult to change but that may or may not be the only damage you have from the overheating. Also, do you know what caused it to overheat? You need to find and fix that problem so it doesn't happen again.
If you decide to tackle the job yourself don't even start without a manual.
Give us the model number from the engine and drive to confirm the year. They are not always the same as the boat.
Here's a link to a 1989...
http://cgi.ebay.com/ebaymotors/1989-REAL-COBRA-OMC-STERN-DRIVE-SERVICE-MANUAL-NE W_W0QQcmdZViewItemQQ_trkparmsZ65Q3a12Q7c66Q3a2Q7c39Q3a1Q7c72Q3a1205Q7c240Q3a1318 Q7c301Q3a1Q7c293Q3a1Q7c294Q3a50QQ_trksidZp3286Q2ec0Q2em14QQhashZitem2ea5caf80aQQ itemZ200350038026QQptZMotorsQ5fManualsQ5fLiterature"
 
I will look for the model numb

I will look for the model number for the engine. I had both risers and one manifold replaced by my mechanic and it still overheated. Yesterday I tried a few things myself. I changed the spark plugs and the engine started right up. I will have a different mechanic and inspect the engine. The engine temp did start to rise. After idling for about 4 minutes the temp started to rise above 180 at which time I killed the engine. I think that it is the water pump in the stern drive that's not functioning properly. One question I do have is if water was entering the engine would it have started and if so what would happen next? (Smoke/vapor)
 
"Will try to compression test.

"Will try to compression test. Any info on how to compression test. I saw some on internet for 2 cycle engines is this the same procedure? Also, my wife startes the engine yesterday and it started right up. After running for 3 minutes it reached 120 degrees but when she cut it off temp rose to 180 and she heard a thump and after several minutes when she tried to crank it it would not move. What could this mean?"
 
Went to perform compression te

Went to perform compression test but the engine would not turn. As per my previuos message my wife started it turned it off and heard a thump. Remove sparks and water came out of 3 of the 8. Checked the oil and the level was good and oil looked good. what next?
 
"Motor should turn over if you

"Motor should turn over if you have all 8 plugs out?? if not I would say you have some internal damage, bent rod maybe? How long has the motor sat with water in the cylinders? rings may be starting to rust to walls, I would spray some oil in all cyl as well for a start. Fairly new engine....were riser gaskets done?"
 
Engine was install last year b

Engine was install last year by previous owner. It is a remanufacturered motor. I was able to hand crank and when I did water came out of spark plug sockets. Once wate was release motor cranked then stopped. Now motor won't crank either electrically or by hand.
 
"You did not state if you were

"You did not state if you were runnig motor while boat is in water, if so your flappers in your exhaust y pipe have probably melted allowing the water to back into the engine through the exhaust manifolds flooding cylinders.Had the same problem with a different situation. If all 8 cylinders are flooding i doubt that there is a cracked head or blown head gasket. what will happen is the water in the cylinders will cause severe damage to the engine if you continue to try and start the engine. Pull your heat risers and look in the exhaust y-pipe and see if your flappers are still in place.if not thats your problem"
 
"Also the overheating problem

"Also the overheating problem could be a bad impeller or a bad thermostat, or blocked water line to yor themostat housing"
 
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