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Water in engine

koffeejohn

New member
I had water coming out of the

I had water coming out of the starboard sparkplugs of my 350 saltwater cooled mercruiser. I changed the intake and head gaskets.I also replaced the exhaust manifold and riser. The boat ran fine for two days. Now I have water coming out of the starboard side again.I used the old bolts for the head and they were not full length due to rust. I also did not put sealant on them. The intake manifold was tightened to specs but when I looked at it now the bolts were not as tight as when I put the gasket on.Do you think it might be the bolts were loose?
 
"Did you use a torque wrench t

"Did you use a torque wrench to tighten these bolts? The torque specs are only valid for clean, dry bolts without any rust or oil on them. ...Re: "used old bolts and they were not full length due to rust" Not a good idea to reuse rusty bolts. I don't understand "not full length"... Did someone cut them short because the holes were full of crap?

Also.."water coming out of the starboard sparkplugs" With the plugs still installed in the engine?...or was there water coming out of the sparkplug HOLES?"
 
The bolts were not full length

The bolts were not full length some of the thread was disintegrated. I removed the sparkplugs and water came out of the sparkplug holes.Thanks for the reply
 
"Words for wise men.
Look lon


"Words for wise men.
Look long, think much, measure twice cut once.

I'm just going to try to relate this event as fact and leave out the colorful language.

73 COHO, twin 350's aft flywheel.
Water was sometimes appearing in the cylinders both port and starboard. Killed the plugs.

At first I just pulled all the plugs, injected some oil in the cylinders, cycled the engine and replaced the plugs. Didn't take that long to get tired of that, six (6) sets of plugs later...

A few days of running the engines let them cool, check for water... no water.. i. e. not coming from the inside, yes that was 10 - 12 cycles in about 40 hours.

Answer: The deck hatch for each engine has a hinge in the middle. That crossed just above the carb and the flame arrestor. Every time I washed the boat, washed the deck, or it rained from the stern. The problem came back.
Water was finding it's way thru the hinge to the carbs, and the intake manifold.

The fix was two stainless steel stove top burner covers from Walmat with a nice hole drilled just right to take the stud from the top of the flame arrestor.

18 months later, the problem has not been seen.
Annual plug change showed near normal ware twice.

Look long, think much, six (6) sets of plugs later I did.

Take good care
Lee"
 
"It is not possible to get pro

"It is not possible to get proper torque with bolts that are that damaged. When you properly torque a bolt you literally stretch the bolt by a predetermined amount. Pull the heads, buy new gaskets (and bolts) and buy a "blind" tap of the correct size and a "T" handle for it. Use it to clean out the threaded holes in the block.

Also, if you've never used a tap to clear blind threads... recommended procedure:
Install tap in the the "T" handle...
Squirt some WD40 on the tap
Carefully start the tap in the hole.
1)Turn CW using finger tip pressure only until it just starts to bind.
2)Turn CCW 1/4 turn
3)Turn CW 1/2 turn
4)Remove tap and clean crap off of it.
5)respray w/WD40
6) Repeat steps 1 to 5 until tap bottoms.
Clean tap and wick out any WD40 in the hole with a thin twist of a paper towel..repeat until towel comes out dry.

Do not be tempted to buy just ANY bolt that fits.
Get the correct one from the manufacturer.

Also while you are at it...check to see if the head is warped or cracked or damaged. If the engine has a lot of hours on it, consider a valve job while the head is off.

BTW... loose bolts on the intake manifold do not usually result in water in the engine...unless the exterior of th eengine is getting wet while it runs."
 
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