mercruiser 170 3.7 ??

first post but you guys have already helped me a ton thx to all... i was having water in my oil i checked the cam seal both were blowen and the weep hold was jb welded closed thx to the last owners i fixed all that havent gotton to the water yet but the question is the head gasket i have 170 #1 165#2 170#3 and 168#4 i belive these are good numbers should i change it or put it in the water ? and hope for the best can a bad head gasket give those good of numbers? i guess im looking for opinions i checked the heat excanger heard water can get in this way anyone with ideas?? thx again

Re: mercruiser 170 3.7 ??

pressure is good. but it can leak oil to water with no efect to the pressure.same with a crack if u dont want a big rebuild or a motor change dont run with water in ther. wont last long

Re: mercruiser 170 3.7 ??

I figured as much...i drained all the old out put fresh in if i run it say 30 min and dont get water it would be safe to say the cam sealswhere the problem right??? The motor ran great and lots of power just the water in the oil ...i figured i better find the problem ill just cross my fingers. Lol

Re: mercruiser 170 3.7 ??

cswitch said:

first post but you guys have already helped me a ton thx to all... i was having water in my oil i checked the cam seal both were blowen and the weep hold was jb welded closed thx to the last owners

i fixed all that havent gotton to the water

yet but the question is the head gasket i have 170 #1 165#2 170#3 and 168#4 i belive these are good numbers should i change it or put it in the water ? and hope for the best can a bad head gasket give those good of numbers? i guess im looking for opinions i checked the heat excanger heard water can get in this way anyone with ideas?? thx again

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Some people's ignorance is astounding!

That is not just water it is antifreeze, as I understand it antifreeze in oil will very quickly ruin bearings. Do not run the engine until it is out of there. I would drain as best I could, put in some cheap oil and a new filter, run for a short time just to circulate the oil and change again with premium (25w 40 Quicksilver) oil and a new filter.

Those numbers look fine to me, no indication of a blown head gasket there.

Water can not get into the engine through the heat exchanger. The reason you got coolant in your oil is because the weep hole was plugged. It is designed so if the first seal fails the coolant under pressure leaks into the space between the seals and then leaks out of the weep hole. The coolant comes into contact with the second seal, but is not pressurized, so it is very unlikely to leak past that seal. With the weep hole plugged the coolant that comes up against the second seal is pressurized and and will leak past it into the crankcase. The weep hole MUST be kept clear.