Mark Maras

[Mark Maras]

Water in the oil!

I have an engine out of a 74-260 Z that reportedly has a blown head gasket with water in the oil. After pulling the pan and head, the inside looks pristine. The engine has 92,00 original miles on it. The oil doesn't have much water in it. The color is dark grayish brown and very opaque. Evidently the engine was not run very long with the emulsion of oil and water.

My question is if the head gasket is not leaking, where did the water come from? The only place in the head gasket that looked bad was up front where it overlaps the front cover.

This is the original engine out of the 260 & I'd like to use it. I'd appreciate any and all ideas that you may have.

I will be pulling the 75 engine out, that came in the car, and will probably sell it to finance more restoration. I also have a complete 71 Z with a very rusted out body but full of very usable parts if any one is interested. location is Portland, Oregon.

Thanks

Mark

[madkaw]

Look again at the HG very closely - maybe you are missing something. It might have been easier to diagnose as a running engine.

FYI - if the 71 still has a motor ( head more importantly) , I would strongly consider using it on the L26 block. Especially if it is an earlier e-88 head.

[Mark Maras]

Thanks For the info. The 71 Z is complete. What are the advantages in using the head and cam from the 71? The 74 engine does have notched cylinders.

Am I to assume the head gasket is the only place that will leak water into the oil with the possible exception of a cracked block?

Mark

[Oiluj]

You might also want to check condition of the freeze plug under the front cover when you have the head off.

[Mark Maras]

Thanks I'll do that. Any other places to check?

Mark

[madkaw]

Do some research on coolant is the oil and check all possibilities. Don't read about too many cracked blocks, they are pretty tough.

What month is the 71? The combustion chamber is better on the early e-88's then the later year/months. Earler head will have smaller chambers and better quench.

[FastWoman]

It's a long shot, but the front-most bolt of the thermostat housing threads into a through-hole that enters the timing chain area right behind the guide/tensioner. Vacuum in the engine vs. pressure in the coolant system... bad thermo housing gasket, perhaps a crack somewhere... Who knows?

[black gold man]

where did the water come from? Condensation maybe.

If the car was not ran until the motor was up to high temp more then just watching the gauge going to 180 you can get water in motor.

Even just sitting a cold motor can condensate when temp outside gets warm and moist just like your beer.

[Mark Maras]

Thanks Guys

I'll check the thermostat housing. I've considered condensation. I don't know much about the history of the engine, When I pulled the pan the oil was an emulsion with some separate water. The engine appears to only have 92,000 miles on it. Not even a ridge in the top of the cylinders. After checking everything I can, I'm going to pull the 75 engine out and reinstall the original 74 engine.

I'm open to any and all suggestions on this project. Keep em coming.

Thanks

Mark

[sblake01]

I once had an L series 4 cylinder develop a crack in the housing behind the water pump. The spring that keeps the radiator hose from collapsing somehow had got into the water pump impeller and it scraped a hole in the cover.

[Mark Maras]

That sounds like another excellent place to check. As I'm cleaning it, haven't started yet, I'm going to inspect all surfaces of the water jacket in the head and block. If I should find anything suspect, does anyone out there have any ideas or experience with testing methods to confirm damage or is this going to be obvious?