VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 Head Gasket? Probably

I've been very busy and haven't been able to post so here we go. After cleaning and detailing engine plus replacing all pan gaskets, motor mounts, radiator plus having near worn through oil pan welded did I find another issue. As time passed I checked the radiator level(as usual) only to discover this fateful day what appeared to be oil in the coolant while the dipstick didn't seem as obvious but probably coolant there too.
-Is there a way to determine if it is just a head gasket and not a cracked block or should I be optimistic and change the head gasket?
-Everything I do on my 38 and the one before is new to me though it may be old hat to others
-Attached are some pics
Thanks,
Mike 38 Master sedan

Looks like crud out of the coolant passages of the engine to me. That looks very similar to my radiator after my engine rebuild. I don't know how the shop doing the rebuild cleaned the block but they probably could have done better. I've run radiator flush through it twice since the rebuild and the coolant is still dirty but better than the images below. The images below were shortly after the engine rebuild.

I bought the exhaust gas test kit from Harbor Freight an used that to test for leaking head gaskets. As Tiny said I would clean the cooling system. I used Evaporust and was please. There are several threads on this site and on the aaca forum on ways to use it.

Water in oil will make it look milky.

I would also do a compression test before going through a head gasket change and would try retorquing the head bolts before removing the head if there looks like a leak.

Dave

i would GUESS the the head is cracked or head gasket is leaking OR the oil line fitting to the rocker arms is leaking coolant behind the side cover.

The radiator, hard to believe is actually NOS, I was wondering if they put some kind of preservative in it for storage and it gunked up when I installed it. Thank you gents for the suggestions, again all is new to me. You can teach a old dog new tricks.

f you remove the spark plugs and one looks as if it was burning different from the others it is probably the head.

When you say NOS do you mean it is a new Chevy/Harrison replacement or the original?

Either way I would definitely have it cleaned and pressure tested under very low pressure. 1938 was not a pressurized cooling system.

I would clean the system first before taking any action. Gene is right and water getting into the cylinder rusts the sparkplug. I would try cleaning with a dishwasher tablet. Modern radiator cleaners are for modern materials not cast iron. See U tube for the dishwasher tablet idea.I have not tried it yet but seems like a good idea.

Thank you all for the advice, I will take the path of least resistance recommended and check plugs and flush system. She sat for almost a year while I was working on her so maybe the gunk from then engine let loose all at once. Keep you posted as usual

If you had to choose one torque wrench for your engine work, which torque range is best? I tried to find the torque values for the head in the 1938 manual but failed.

If you can find one that covers 10 or 20 and up to a max of 150 it will cover your needs.

Remove the side (push rod) cover and if the plugs look OK, check the rocker arm oil line to block fitting next,

There were no torque specs in those days. Go fora final torque of about 65 ft lbs in 3 steps and in the pattern shown in the manual.

Eek, no kidding. I assumed they had them but couldn’t find it so there you go. Thank you for the specs

Not knowing the history of the engine just since you've had it, would it be reasonable to start fresh? As in, since whatever thats in the water system is obviously garbage, maybe just spend an afternoon flushing everything out, You can drain from the radiator but also from the rear engine petcock. I did mine recently and found that if I blew air back through the petcock a little (off and on). Let it drain until it slows then blow back up then let it drain some more. Mine would start to clog then I'd blow some more. I did this until everything drained clean then filled it with 50/50. I was shocked how much more crap was dislodged with just a little air pressure.
Also water in your oil doesn't always show on the dipstick. Only when I drained the oil into a pan could I see the tell tell milky look.

I tend to agree as I will have to drain all fluids, cooling system to clean and oil to check and I suspect their is coolant in the oil as it looks a bit thin in viscosity as well as change my oil pan gasket as it had a small leak after replacing but the last time. I’m trying to figure how to accomplish this and how to store all the fluids to dispose of them properly and not down the drain. I wish I had a shop to work in instead of my track home garage but at least I have a garage. I want aaare of a drain in the block but makes sense. I don’t have an air compressor, haven’t needed it so far but might have to get one
Thanks

As for storing the liquids, any large plastic bottle (like empty engine coolant bottles, or empty one gallon water bottles) that are made from PEHD (polyethylene high density) will hold up to the chemicals.

PEHD bottles have a number 2 on the bottom for recycling purposes. This is the same material they use for plastic gasoline containers.

Cheers, Dean

Hey we all started with either our tiny a55 1 car garage or our back yard in the grass. Some day you'll look back on this and wonder how you got by without your 1500sq ft of heated and cooled. But you WILL get by. Oh, and there will also come a day when you actually have all the tools you need for almost every job. Sounds funny now but you'll get there.