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Water in Engine Oil Any Suggestions

S

Steve McCarty

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"I have a 95 Caravelle with a

"I have a 95 Caravelle with a Ford 302. I just had a new Ford 302 engine installed with a 351 Cam. I put in a new engine because the Ford 302 engine before was getting water in the oil. I took it to a boat shop and they said the block was cracked. So that is why I put in the new engine.

Now the new engine is getting water in the oil too. So obviously the mechanic at the boat store didn't have a clue. I have heard that it could be the flapper in the y pipe, possible the intake manifold, maybe the gaskets on the exhaust manifold. Any help on what I can do to see what is causing the Problem."
 
"All of the above, along with

"All of the above, along with a lack of (or inoperative) exhuast flappers, and possibly poor operation (slowing down too fast). Gotta start looking at one piece at a time. Sorry.

Jeff"
 
I would start with the intake

I would start with the intake and gaskets. There are several types (gotta love fords better idea) and the wrong gaskets will leak. Seen it many times.
 
Maybe the mechanic knows more

Maybe the mechanic knows more than you think he does. Sounds like he may know just how to remove a lot of money from your pocket without doing a thing.
If it were me I'd make him fix it at no futher charge.
After all he was the one that said you needed a new engine and is also the one that did the repairs if I'm reading this correct.
 
I didn't let the mechanic

I didn't let the mechanic that told me I needed a new engine install it. They seemed a little shady so I won't go back there again.

Once I had the new engine installed we just let the boat in the water for maybe 10 minute tops and it mainly just idled we didn't get on it at all to test it. So the water is getting in the oil at just idle. Do you think it is just the flapper or could still be the gaskets or possibly the intake manifold?
 
"Also, leaking exhaust manifol

"Also, leaking exhaust manifold to riser gaskets can let water in. Better check them as well.

Jeff"
 
"Steve, How old are the exhaus

"Steve, How old are the exhaust manifolds? Do you boat in salt water? Water can enter the motor if the manifolds or risers rust through from the water jacket to the exhause passage. The water then runs into the cylinders via the exhaust valves."
 
"The exhaust manifolds leaking

"The exhaust manifolds leaking may let water in but the engine would hydro lock at some point if this was the case plus there would need to be a lot of water for it to get into the oil past the pistons.
There must be a leak between the water jacket and the oil system at some point. A leak down test could be the only way to find such a leak. Any other way is just guessing and can be very expensive and take a lot of time.
Did you replace the heads as well when you changed the engine? If not there could be a crack on the top side of the head. I've never heard of this but I guess it could happen. The flappers are over rated as a cause for water getting into the engine. Frist they do not seal out water. These are more for back wash from slowing down to fast or to keep water from a wake getting into the manifold should the boat be at a dock and be hit by a wake from behind. The flappers will move very easy if the boat is just bobbing in the water and not running.
The water would need to be above the dead rise of the manifold for water to enter from the exhaust port on the back of the boat
In other words the boat would need to be lower in the water than the lowest point of the exhaust riser. In this case the top of the drive would be about 8" under water.
There are not many ways for water to get into the oil system. Cracked block,cracked head, cracked intake above lifters,bad intake or head gasket.
Now I'm not a Ford guy but a chevy will leak if some of the bolts that go into the water jacket for holding the intake on were not installed with sealer on them. This will show up on top if you're lucky but I've heard of them leaking into the lifter gallery with no other sign of leaking.

The thing is you had the problem before you started and the chance of still having the same leak is rare. What parts did you use from the old engine?"
 
"Charli has made several good

"Charli has made several good points. Water in the oil is not the same as water getting into a cylinder from the exhaust. (I missed that. Doh!)

A few years back, when I was building kit cars, I rebuilt a Caddy 4.9 V-8 (to go in my Fiero). This motor is notoriously difficult to rebuild in that it can leak water by the replacable sleaves. To be certain I had the thing sealed up tight, I pressured the completed motor to 15 psi by filling the block with water and sealing off all the openings with pipe caps and etc. I then closed the air valve and let it sit for hours, and the pressure did not drop. You might want to try that.

Jeff

PS: Oh, to make the test more valid, you coud warm the motor up first and use hot water."
 
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