Engine oil disappearing.

[Don1500]

I have a major problem. My engine oil is disappearing and it is not going into my bilge. I have a Westerbeke W27, raw water cooled. I spoke to a mechanic in Fernandina and he said that I need to change the oil cooler. I went through all the manuals and couldn't find where it is. It has to be either the exhaust manifold or the heat exchanger but I can't find any oil input or return lines to either. Both are over $1000 so I want to know which one I should change, or is it something else. Yes, the zinc is shot.

[DeepFrz]

If it is a raw water cooled engine you wont have a heat exchanger so if you see a heat exchanger it might be an oil cooler. If you have an engine with coolant being cooled by a heat exchanger then there are aftermarket heat exchangers for less, but should not affect the oil.

How much and how fast are you consuming oil? How is the engine running? Smoke out the exhaust? What color? Running rougher than usual?

[irwin37]

Just a thought but not all engines have an oil cooler, My 4-108 Perkins certainly does not and I believe they are similar.

[Randyonr3]

You are probably burning it... Especially if you are running it at high RPMs or if the rings are going bad..
Its common to suck the oil up past the rings in a diesel, and the motor will burn it just like fuel.......

[zboss]

Originally Posted by Randyonr3

You are probably burning it... Especially if you are running it at high RPMs or if the rings are going bad..
Its common to suck the oil up past the rings in a diesel, and the motor will burn it just like fuel.......

Are you producing blue smoke?

[Mycroft]

Are you sure it's raw water cooled? If you have a radiator cap, then it's most likely that your engine is cooled by raw water going through the heat exchanger to cool the anti-freeze.

If no radiator cap, then any heat exchanger would be an lube oil or transmission oil cooler.

[Don1500]

Originally Posted by zboss

Are you producing blue smoke?

I "burned" about 3 quarts in 7 hours. There is some blue smoke in the exhaust but it looks more like steam mixed with the raw water in the exhaust. There is antifreeze that is cooled by the heat exchanger (big round tube at the back of the engine) and the antifreeze goes through the rectangular exhaust manifold (with the radiator cap) on top of the engine. Engine temp runs about 170-180°F all the time (after warm-up).

[sailorchic34]

If the engine starts easy, HOT OR COLD I would suspect a blown head gasket.

If the engine is hard starting HOT OR COLD, it could still be head gasket or more likely rings.

I should note that when my engine broke all the rings in one cylinder I was burning a quart every 7-8 hours and it was a bear to start, hot or cold.

Any water in the oil, it would be grey gunk??

[Yeti]

Originally Posted by Don1500

I "burned" about 3 quarts in 7 hours. There is some blue smoke in the exhaust but it looks more like steam mixed with the raw water in the exhaust. There is antifreeze that is cooled by the heat exchanger (big round tube at the back of the engine) and the antifreeze goes through the rectangular exhaust manifold (with the radiator cap) on top of the engine. Engine temp runs about 170-180°F all the time (after warm-up).

That kinda sounds like a fresh water cooled engine to me. My old engine was a raw water cooled engine that was converted to freshwater cooling. No radiator cap on the engine at all. just one on the heat exchanger that was added to make it fresh water cooled.

I believe its also fairly common for fresh water cooled engines to run at the temps you quoted and for raw water cooled engine to run at lower temps around 150-160F.

A quick Google search shows that the W27 should be freshwater cooled.

While I'm no expert and haven't looked at it with mine own eyes. It sounds like you have a freshwater cooled engine in need of a rebuild.

[Charlie]

I would think that you would want to perform a few tests before replacing expensive items. I would start with a compression test. If that is bad most likely cause is rings. pour a tablespoon of oil in the cylinder and then if the pressure goes up your rings or cylinder is leaking. If pressure is good I would try a leak down test. This will pinpoint where the fault with the engine lies. It could be valve seals as well. On a friends car we replaced the PCV valve (never seen one on a boat though) and he went from consuming a quart every 80 miles to not noticeable oil consumption. You can buy the tools from harbor freight cheaper then you can get a mechanic for a couple of hours. Eric the Car Guy is good at teaching how to do the tests. YOutube is your friend.

[Don1500]

Originally Posted by sailorchic34

Any water in the oil, it would be grey gunk??

No water in the oil.

[a64pilot]

This was a sudden change right, went from using little oil, to suddenly using a lot?
If so that sort of eliminates being worn out, engines don't usually wear out quickly, but could be broken rings or head gasket.
I'd start with a compression test, that should tell something, if compression's are fine, it could still be a head gasket though, it's not common for oil to leak to the water through a head gasket, but it does happen occasionally.

We've eliminated the oil cooler? If it has an oil cooler and compression's are good, then that would be where I would look, easy to pressure test an oil cooler if it's the kind with hoses

[a64pilot]

Originally Posted by Don1500

I "burned" about 3 quarts in 7 hours. There is some blue smoke in the exhaust but it looks more like steam mixed with the raw water in the exhaust. There is antifreeze that is cooled by the heat exchanger (big round tube at the back of the engine) and the antifreeze goes through the rectangular exhaust manifold (with the radiator cap) on top of the engine. Engine temp runs about 170-180°F all the time (after warm-up).

I don't know anything about a W27, but you sure what your calling the heat exchanger, isn't the oil cooler? (Big round tube at the back of the engine?)

I think maybe the the square tube with the radiator cap may be the heat exchanger

[sailorchic34]

If it has a oil cooler, bypass the raw water around it with a long hose and run the engine. If you see oil dripping out the open water ports, its a bad oil cooler. Running the engine for 15-30 minutes without the cooler water lines hooked up, will not hurt anything.

If the engine has a oil cooler and starts easy, odds are its a leaking oil cooler. Round thing on the back with raw water and small oil lines going to it.

It could also be a blown head gasket, but that's a lot of oil loss for a head gasket, or broken rings. But broken rings would make the engine very hard to start. Been there done that.

Just checked and the W27 DOES have the oil cooler.

[MarkSF]

Originally Posted by Don1500

I "burned" about 3 quarts in 7 hours. There is some blue smoke in the exhaust but it looks more like steam mixed with the raw water in the exhaust. There is antifreeze that is cooled by the heat exchanger (big round tube at the back of the engine) and the antifreeze goes through the rectangular exhaust manifold (with the radiator cap) on top of the engine. Engine temp runs about 170-180°F all the time (after warm-up).

One minute you say its raw water cooled, the next you describe a fresh water cooled arrangement.

How hard can it be to LOOK and see if there is oil cooler?