Hi Guys,
Finally got the 500 finished, details to follow at a later date. I need a plug for the freeze plug hole which used to contain the block heater, OR, I need to find another block heater.

Any suggestions??

It is a very strange size which I could not find a freeze plug to fit.

By the way, this motor pulls like a Gorilla. You would not believe the grunt it generates. It is in my 66 Ford Pickup, and my combined Gross Vehicle Weight is right at 13,000 lbs. I just pulled a serious grade in drive @ 2200 rpm..... no sweat. Killer Motor........

Thanks, more info to follow in future, we learned some things building this motor that I had not seen posted in here before.

Regards,

UBA40

Block heater? I don't think 500's had those? Or do you mean the outlet that goes to the heater core?

Caddydaddy,

My '75 500 has a block heater but I live in upstate Minnesota (car was bought in North Dakota new) so he cant have it! Sucker still works after 32 years, too.

UBA40

Shoot, I wish I could get part number for ya without taking it off. It doesn't leak and I don't want it to start now! One question for you though, how did you run it with a hole in the block, or did you just plug it up with the junk heater? I would check a local caddy dealer's parts counter and see if they can order one for you.

Cheers,
Tyler
:cheers:

Any awful parts house with a Dorman catalog can supply you with the original core (freeze out) plug. You can even get them in brass. Avoid the ones with the screw in the middle. The punch in types work fine if installed properly. Change all of them if the engine is out.

As it turns out, the block was bored through to an unusual size. The freeze plug is not in anybodys book, that I could find. I have a rubber expandable freeze plug in that opening now, but am not comfortable with its projected longevity!!!

Since completion of this engine, I have put around 1,000 miles on it. I have had to tighten it about twice during that period. (makes me nervous)

When I posted the question, had presumed the block heater was common in the North East, and that someone might have known an immediate solution.

Thanks Group. I do appreciate the input. If I had the size of that opening as I write this, I would have posted it, but was a wierd size like (1" 27/32)....

Boy oh Boy, does this pull a Load!!!!....... 13,000 lbs GVW..... 8.9 MPG @ 60 MPH WOW!!!

http://www.partzfinder.com/Cadillac_V8_Brass_Freeze_Expansion_Plug_Kit_p/pio-pe-120-b.htm