There is a new post today that I believe is a 1953 Canadian 235 that got me thinking. Do all Canadian 235/261 engines have this extra pipe plug on the side of the block? I don’t believe any US engines have this plug. See picture below.
Can confirm The default 53 Canadian 235 engines block: 5843350 head: 3701887 All have that big plug you show I have never removed one but I’m 99% sure it’s the water jacket because I had one with a hairline crack below that plug and coolant was seeping out the block in that location. -s
The Canadian engine blocks were all cast at a foundry in St Catherine's Ontario, (not very far from Buffalo). GM had purchased this foundry years earlier from MacKinnon Industries. Why they were different, who knows.
All 4 of my 235’s have the block heater mounted more towards the front of the engine, one of my engines is a 52 splash oiler and it also has that big pipe plug. Engine number is 3835814
This pipe thread hole is a bit smaller I think than the normal smooth hole block heater which all my engines have You pop out a frost plug and that’s where the block heater goes This threaded hole is always a pipe plug like the photos. Maybe it’s for an older style block heater standard used in Canada? Anyone have old Canadian parts books? Look up block heater options Hole looks to be about 1inch pipe thread? -s
There are still block heaters that use pipe threads, but most I've seen would go quite far into the block and may not have room at that location. The ones that go in a freeze plug hole are usually a bent pattern and wouldn't work on a threaded hole. Here's one that might work there. Link
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
