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Oil in coolant

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norton

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"86 merc 190 - Replaced the he

"86 merc 190 - Replaced the head with a rebuilt one this year, took it out for a run and when I came back there was oil in the coolant tank. Is this a cracked intake or did I screw up one of the gaskets?"
 
"Sorry - 1986 Mercruiser In-li

"Sorry - 1986 Mercruiser In-line 4 cylinder -190 HP. Last year was running low compression (105 lbs) in # 3 cylinder due to a cracked valve. I had an extra head when I bought the boat and had it reconditioned. I installed it at the end of last season, took the boat out for one run and seem to run fine but had to put the boat away for the season before I could do a complete shakedown. Compression is now 150-150-145-135. Number 4 is low to some scoring I noticed on the piston wall. I've had the boat out twice now and the second time is when I noticed about a half of cup of oil accumulated in the coolant tank reservoir. Today I retorqued the headbolts because I hadn't before and the book recommends doing 3 times (overkill?) I ran the boat today but didn't check the tank to see if any more oil is there because it was still hot. I'll find out tomorrow. I'm starting to think I didn't use the correct torque because the bolts went a lot more turns to seat to 130 Ft- lbs. (I might of done only 90 lbs spec that's for an in line GM)."
 
"Good news - No oil but I'

"Good news - No oil but I'll keep an eye on it, time will tell. Whether it might of been wrong torque or not re-torquing the 3 times cause it is a guess but a lesson learned on following the book to the letter. It's such a pain in the butt because you have to remove the rockers each time you do it, I wonder if everyone does the 3 times? As for the oil cooler on the bottom of the intake manifold, has anyone seen those fail or crack before? Just wondering."
 
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