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Hi All,
We had great weather here over the weekend, so I started work again on the 300.

As you recall from "The Big Coolant Disaster" I had an exhaust manifold stud that popped out and coolant spilled out.

Well I just put the manifolds back on and decided to drop the oil pan to clean things out. I removed the oil drain plug and coolant poured out, followed by the oil that was sitting on top.

I am at a loss. I've never had coolant in the oil before.
How did it get there from it leaking out the exhaust manifold stud hole? The engine hasn't turned over since this ordeal began. Coolant in the oil was not something I was expecting.

Cracked block?

Wonder why the stud pulled out and what was done beforehand. There was an incident where a mechanic drilled out a broken stud in a 53 and proceeded to drill too deep and thru something into the water jacket. Stud was replaced and thinking that and sealant would fill the hole, no one thought any more about it. All appeared well until the radiator was filled and water came pouring out of the carb. Not sure exactly where the path was but water could get into the manifold. The hole had to be thru one of the valve areas as well and stud wasn't long enough to fill it. Perhaps if something similar happened, that same route is open to the crankcase and opened when the stud was replaced.

Howard, good question. To quote the owner:

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A crack, the head gasket, however, you have to dig deeper.

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Dave, when's the last time a compression test was made?






[picture source:thejunction.de/zwiegespraech/2008/07/15/liquid-interaction-00579]

My theory is that when you had the coolant gushing out the stud hole, that it went into the intake or exhaust port and then down the cyl into the sump. I could see a cup of water doing this, but not a whole lot...Or perhaps the coolant gushing out the stud hole just flowed into the valve cover and then directly into the oil sump? -Also the fuel pump is there, could have been the coolant go in through there somehow. Was oil leaking on that side of the car when it was running?
This would be the most optimistic scenario with no cracked blocks and assorted doom and gloom. If you have the stud back in place, you could re-fill the coolant system and pressure test that. Easier than a compression test, or head removal.

Tobs, that's my theory as well.
There was some oil spatter from a leaky valve cover.
That would be ideal if it all went that route, but I suspect a good deal of water went down the exhaust/intake ports.
I'm thinking I should probably remove the manifolds again and shoot some PB blaster down into the block through the ports.

I'm still going to run the compression test (good idea no matter what). I don't have a 10mm adapter for my gauge, am going to try a small engine place here in town and possibly the farm stores to source one. Although, if I shoot the pen n oil, there goes the dry test....

We'll start small and go from there....

If you can't find a 10mm adapter for your compression gauge, it's only about 5 minutes to make one from an old 10mm spark plug. Just break the porcelain, remove the guts, and optionally chamfer the opening a bit to better fit the rubber tip of the compression gauge, if needed and if that's the style gauge you have.

As far as coolant in the crankcase via the valve ports, I've seen it on the later old detachable-block eights (320 and 385 engines), though the entry route was a bit different. On those engines the exhaust manifold flanges just slight overlap a core plug and if the plug leaks, the coolant floods the exhaust manifold and from there apparently made it's way to the crankcase via the guide clearance and/or the rings. This surprised me as I'd have thought it would run out the exhaust manifold to the header before it could reach that height.

Uh, I'm wondering why you have 10mm plugs? That means that someone has put an old bathtub head on your car and dropped the compression a point. Whilst you are playing......

Yup, the head is a '48.
Ain't it swell.

The first time you remove the manifolds can be a daunting task. Once you have them off, it wouldnt hurt to go ahead and adjust the valves. As to the chips getting in the water jacket, hold a shop vac as close to the tap as possible.