46 pickup overheating problems

[Deleted User]

I recently replaced the radiator on my 46 p/u and am still experiencing high engine temps and overheating. I pulled the water jacket manifold off and found a ton of rust/crud build up. I cleaned everything that I could get to (including the holes coming down from the head, three were completely plugged) and back flushed everything as well as I could. Does anyone know of a flush additive that is more aggressive than the stuff that you can get at the autoparts store?

[Deleted User]

I forgot to mention that it has the stock 212 cid 6 cylinder engine

hudsontech

When you pulled the water jacket what condition was the baffel plate in?? I recently had a 34 Terraplane owner pulled the water jacket off and found all sorts of goodies and the baffel plate was pretty well gone.



I have a tech bulletin that tells how to make one of these baffles, including a diagram with dimensions that I can email to anyone who needs one.



Ask for TS 84-2, Rebuilding the water distribution baffle, 3 x 5 six cylinder engine.



Hudsonly,

Alex Burr

hester_nec@yahoo.com

[Deleted User]

Alex,

sent you an email

the baffle has some extra holes that weren't intended by the factory

[Deleted User]

Well, I made a new baffle, welded it into the manifold, scraped and cleaned as much crap out of the water jacket as I could get to and it still runs way hot, its not boiling over but its hot. I figure the next move will be to remove the water pump and make sure its up to snuff. If that checks out I may remove the head and clean the water passages on top of the engine....any other thoughts?



Also, my hood is missing the cowl piece/shroud that used to be between the radiator and leading edge of the hood. Is this piece vital? Should I fab up a new one?

Unknown

Yes, you should make sure that the shroud is there. Another item that is missed all too often is the fan blade itself. Make sure that it hasn't been bent and that all the blades have the same pitch. If it has been 'stepped on' and flattened somewhat it will not pull sufficient air through at low speeds. Hope this helps.

Jon B

Just curious...you said, 'replaced the radiator'. With a new or re-cored one, or with another used one that looks to be in good condition?

davegnh

R u sure the motor is really running hot? These temp gaugues are sometimes way off. Do you have a thermometer that you can stick in the radiator? What about an aftermarket gauge so you know what is happening? Is it boiling? My 46 gauge shows it is running hot but the thermometer in the rad shows 165, or somethig like that--

rambos_ride

I agree with davengnh1 - check the temp manually with another gauge or thermometer.



Another thing is - what is hot? How hot is it getting? Is the thermostat opening up when it supposed to?

[Deleted User]

I was thinking I might try an aftermarket temp gauge.

It has been blowing steam and coolant out of the overflow hose on occasion

There is no thermostat at the present time.

Jon B

I have been told by some, that in the absence of a thermostat the water runs through the system (and radiator) so fast that it never has time to cool down in the radiator. Thus, it runs hot. The thermostat slows everything down, and the water has time to be cooled, during its trip through the radiator. However, if you had this trouble before you removed the thermostat, that would shoot holes in the theory! Let me just conclude by saying that I too have a 212 engine (a 1937 version) and have never experienced overheating (well, once -- when the thermostat jammed shut!) in 30 years of operation. So there's hope!

[Deleted User]

I was talking to a guy here who suggested that it could be the problem, It did over heat before I removed the t'stat but It was because the radiator was leaking/gummed up. I'll try a new thermostat and see what happens.



Anyone know the P/N or where I can get get one?

Unknown

Check the Thread I posted on 37 water jacket a couple of months ago. The forum had some really good advice.

[Deleted User]

I have access to some t-stats that are known to fit 48-54 308's and 262's are they the same as my 46 212?

Jon B

I believe there were only one or two sizes of thermostats for most American cars during the 40's (I bought my last one at a regular auto parts store). If you have the regular style of water neck and water pump you can simply use this (should be same as Step-Down), so long as it fits snugly.



However, if you have the BYPASS type of setup (neck on top of head has large and small outlet, water pump has two outlets as well), I believe you need a special, taller thermostat with a little 0-ring at the top.



Hey -- have you checked your water pump innards yet?

Uncle Josh

Auto Zone, and others I'm sure, have a mechanical (copper tube) stat that you can hang under the dash and watch for a while.