1936 Pontiac Silverstreak Canadian made

[Silverstreak36]

I have recently purchased a beautiful 1936 Canadian made Pontiac Silvestreak 6 cylinder all original. I have two problems,

1) I'm trying to find the motor I'd as I was told it is not the original motor, I have the original sitting in my garage.
Here is what I have found.
On the front corner driver side just below the valve cover is the following numbers 517139

On the valve cover is the numbers what looks like a C 512119

On the lower part of the passenger side below the starter is the markings J 14 2

On the valve covers is written gm4

I was told this was a crate motor bought in the 1970's but I don't know what year is it.

Problem 2 when the car is left idling for a while then turned off, then turned on again, my coolant boils over and spews out of the filler cap. It is green coolant I think. Temp gauge reads 190.

Thank you I am new on these so I'm learning.

 

see Google drive photos that may help 

 

Pontiac 36

 

 

[dictator27]

If you are filling the radiator up right to the bottom of the filler neck, that is your problem.  Cars of this vintage need at least an inch of space in the radiator top tank to allow for coolant expansion.

[Bloo]

These are a weird setup. It is a crossflow radiator, and you cannot see the level when it is filled properly. There is a petcock on the side to check the minimum. It is possible to run it higher for a little more capacity in the summer (not clear full of course) but you would have to check the shop manual. I do not recall how much extra you can put in over the petcock level.

[Guest]

Nice looking car.

[pont35cpe]

1939 was the last year that had the "Pontiac Head" on the side of the block.

[58L-Y8]

Good-looking '36 Pontiac you have there.  This forum is where you should address your flathead-era questions:

Pontiac Flathead Owners - Antique Automobile Club of America - Discussion Forums (aaca.org)

[Silverstreak36]

I will send the question there thanks 

 

[Rusty_OToole]

There was a unique Canada only Pontiac in the thirties that used a 224 cu in version of the Chevrolet overhead valve six. All others used the Pontiac flathead six. You speak of valve cover as if yours is the OHV?

[Guest]

 Quote " my coolant boils over and spews out of the filler cap"

 

 I would drain and flush the coolant system, then put a radiator cleaner/flush in it and drive it for 2 - 3 days.

 Drain and flush again until clear.

 Re fill with Green antifreeze. and enjoy happy motoring  .🙂

 

 Roger

[Bloo]

This one is a Pontiac six, although newer. See the pictures in the OP link.

[Silverstreak36]

Do peek at the link below for the photos of the car

 

https://photos.app.goo.gl/NLT9Fc5tAcea5eFfA