Water in Oil Atomic 4 Catalina 27

[SailorJim123]

Hello,

I just purchased a 1977 Catalina 27 and have been informed by the previous owner that there is water in the oil. From reviewing the message board here I know it is advised to change the oil three times, however he says that he has and there is still water. Other than that he states the engine runs great.

What should be my next course of action? Is there anything else I can do myself to check it out and possibly fix it or do I need to seek a professional? If I do need to find a Mechanic, does anyone know a qualified Atomic 4 mechanic in Florida?

Thank you in advance,

Jim

[tommays]

Could be a LOT of things so rather than guess

I would start with a compression check as most ways the water would get in would have dammaged other parts of the motor

If it comes back good you can look at the exaust manifold or other rusted through part

If comes back bad gotta look at a bigger problem

[JimsCAL]

As Tommays says, there are lots of possibilities including head gasket, seals in water pump, corroded head or exhaust maniford from raw-water cooling, etc. Just have to take thme one by one until you find the cause.

[jaschrumpf]

Originally Posted by SailorJim123

Hello,

I just purchased a 1977 Catalina 27 and have been informed by the previous owner that there is water in the oil. From reviewing the message board here I know it is advised to change the oil three times, however he says that he has and there is still water. Other than that he states the engine runs great.

What should be my next course of action? Is there anything else I can do myself to check it out and possibly fix it or do I need to seek a professional? If I do need to find a Mechanic, does anyone know a qualified Atomic 4 mechanic in Florida?

Thank you in advance,

Jim

Hi, and welcome to the wonderful world of the Atomic 4.

I have an A4 in a 1975 Newport 28 that I bought from a guy who didn't know why he had to flip the switches he did to start the engine (there were two different fuel pumps in the boat!), and I've parlayed my basic learned-to-drive-in-the-'70s engine knowledge into a deep appreciation my the A4 in my boat.

To get to your problem, there are several reasons why water would show up in the oil. First is by cranking the starter for a minute or so without the engine firing. The A4 depends on exhaust pressure to push the raw water cooling flow back out of the engine, so if you crank it for over 30 seconds or so without it firing up you might just flood the cylinders with water.

If that's not the issue, you might have a leak in the head gasket, or even the head itself.

Do you know if the engine has ever been rebuilt? If not, you may well have the old paper head gasket which is very susceptible to burn-throughs during an overheat episode. I had that very thing happen to me during the first season I owned my boat. I fixed my problem by taking off the head and replacing the gasket with the new double-layer metal gasket from the King of A4s, Moyer Marine (www.moyermarine.com).

Lots of stuff to check, but you can begin with this: get a compression tester and get a reading on all four cylinders. If they are all within the 85-105 range you are in good shape. If you have low readings on two adjacent cylinders you most likely have a blown head gasket.

Let me assure you that the above is not a big problem. Unless you have zero accessibility to your engine in your boat, getting the head off and cleaning and prepping it are not a big deal.

Take a bit of time and run the test I recommended, then get back to us.

Good luck!

[sailor50]

It could also be the fuel tank.

[fordo]

In addition to the above mentioned items [head gasket, exhaust manifold, etc]there is another, less likely, possibility. According to Mr. Moyer cracks sometimes develop in the floor of the water jacket around the cylinders on the starboard side allowing water to drip into the oil in the crankcase. This is repairable with fiberglass and west epoxy. Also, in the later A4's there is a steel plug between the water jacket and the valve rods. If this fails, the water floods into the crankcase creating an unholy mess as the oil and water gush out of the engine into the bilge and carburetor. [I know from personal experience]

These are unusual problems. If the head gasket is good it's probably the exhaust manifold. It would be a good idea to get the Moyer manual for the A4. It was a great help.