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120 hp mcm mercruiser

Z

zootschief

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This forum is awesome.I have a

This forum is awesome.I have an issue maybe someone can help.I just replaced the head gasket on my mcm 120.Had trouble starting so took compression test and with all plugs removed I am getting about 130 psi.While turning the engine over I noticed water coming from #1 plug hole.Can this only be the gasket.The head looked good(no cracks visible) and was never overheated.
 
"cracked manifold, cracked blo

"cracked manifold, cracked block, leaky gasket
You did do it in 4 steps and in the proper order?"
 
"I had a crack (hair line&

"I had a crack (hair line) on my inline 6 #1 plug hole, right at the base of the plug, had a guy PIN it.. can't even see it and doesn't leak.

rare though I guess."
 
Does anyone have the 4 step pr

Does anyone have the 4 step procedure in text.I used torquing sequence from manual.But not sure of the 4 steps.
Thank You JOhn
 
The most commen thing would be

The most commen thing would be a corroded out exhaust manifold. They tend to start at the back of the engine since that's where the water sits. Check that first. The 120 is pretty bullit proof since it's all cast iron block and head. If you tightened down in sequence you are probably OK especially since your compression test shows good comp.
 
"well the serial number (l

"well the serial number (last 3) are 74G however the previous owner reg'd as a 75, it does say 21' on the side, so when I look it up I see 22' on iboats and the boat pricing guide. there are no 75s listed, the engine when I got it 8 yrs ago was and is from a 74 Nova (traced the serial on the block)

I have pics of a couple and I just searched and looked at pics of a 76 and it looks Identical from the screen door, dash & steering wheel & inside boards, minus the OMC equip.

more of mine here.. http://gallery.kainonmedia.com

76 Islander

http://ottawa.kijiji.ca/c-ViewAdLargeImage?AdId=134557169&img=http%3A%2F%2Fimg1. classistatic.com%2Fcps%2Fl%2Fkj%2F09%2F6%2F10%2F516%2Fr1%2F0539j2h_18.jpeg"
 
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