water in oil

bought a 1988 regal boat with 3.0 merc-cruiser drive unit.had it running a couple of times with water hose but not in water yet.guages all reading good.was going to take it for a ride and notice water in the oil.not just a little water,it was very milky.i've changed and rebuilt a few motors but boat motors is a new adventure for me.notice a couple of things,(1)water was coming out between the motor and belhousing,mainly on the right side,is there any freeze plugs on the back of this motor in that area?(2)water dripping out of an open hole on the intake/exhaust manifold just above the drain valve.can a bad gasket allow water to get into the oil or would this be a head gasket problem?or something worse.jeep john

Re: water in oil

Sounds like a headgasket or cracked head

Re: water in oil

jeep john said:

bought a 1988 regal boat with 3.0 merc-cruiser drive unit.had it running a couple of times with water hose but not in water yet.guages all reading good.was going to take it for a ride and notice water in the oil.not just a little water,it was very milky.i've changed and rebuilt a few motors but boat motors is a new adventure for me.notice a couple of things,(1)water was coming out between the motor and belhousing,mainly on the right side,is there any freeze plugs on the back of this motor in that area?(2)water dripping out of an open hole on the intake/exhaust manifold just above the drain valve.can a bad gasket allow water to get into the oil or would this be a head gasket problem?or something worse.jeep john

Click to expand...

Ayuh,.... Welcome Aboard,...

Unfortunately, you bought a boat with a frozen, cracked block...

Sounds like all the coreplugs are blown out too....

It's much, Much worse...

Re: water in oil

Bond-o said:

Ayuh,.... Welcome Aboard,...

Unfortunately, you bought a boat with a frozen, cracked block...

Sounds like all the coreplugs are blown out too....

It's much, Much worse...

Click to expand...

i ran motor a couple of times with no issues.motor starts up fine and guages all read fine.hoping this is a head gasket problem or freeze plug issues.i'm still not sure if manifold gaket could cause this or not.

Re: water in oil

a head gasket or manifold gasket would just dump water into the cylinders and cause the motor to hydrolock

having water in the oil means a cracked block - especially considering you have one or more core plugs pushed out, someone didn't winterize the engine properly and you now need a new one

if you simply run the motor and don't let it get to temp, the crack(s) will not allow much water into the block, they need to expand with heat to get a lot of water in the oil - not to mention with the core plug(s) out, there is little to no water pressure in the cooling jackets to force water through the crack(s)

Re: water in oil

dubs283 said:

a head gasket or manifold gasket would just dump water into the cylinders and cause the motor to hydrolock

having water in the oil means a cracked block - especially considering you have one or more core plugs pushed out, someone didn't winterize the engine properly and you now need a new one

if you simply run the motor and don't let it get to temp, the crack(s) will not allow much water into the block, they need to expand with heat to get a lot of water in the oil - not to mention with the core plug(s) out, there is little to no water pressure in the cooling jackets to force water through the crack(s)

Click to expand...

any tests i can do before i pull the motor out?

Re: water in oil

jeep john said:

any tests i can do before i pull the motor out?

Click to expand...

sounds like you already have, but...

you can change the oil and filter until the oil is fairly clean

get a good mark on the dipstick and let the engine run till it pukes out oil or gets milky to the point its obvious the block is cracked

Re: water in oil

i found a 2.4[i think]out of a runabout.runs great.will that bolt up in place of the 3.0 motor?would rather put another 3.0 in but i was told i would loose only about 10 hp. jeep john

Re: water in oil

jeep john said:

i found a 2.4[i think]out of a runabout.runs great.will that bolt up in place of the 3.0 motor?would rather put another 3.0 in but i was told i would loose only about 10 hp. jeep john

Click to expand...

Ayuh,... A 2.5l will swap, never heard of a 2.4...

Re: water in oil

same here.i've heard of the 2.5 but he said 2.4.the guy that told me was not owner of motor,just a friend of his.may get it to run in for the summer. thanks. jeep john

Re: water in oil

Could run a compression check to eliminate the head/head gasket....