Last Saturday was super hot, hit 33°C. I drove the car on the highway, then stop & go traffic. When I got home the radiator was overflowing and temperature indicating 250°F which I never before saw such temperature.
Last year I changed the thermostat on my 67 2+2 since I had a similar issue but now I noticed that the radiator was really hot by the top and cooler or more normal towards the bottom. Wonder if it's clogged.
What should I do? Flush it or simply replace it (visually it looks original)
If I replace it, anyone can tell me what type I should replace with to get the best results. Should I get a 5-core or a 4-core?
I also had some over heating issues on the hottest of summer days with my 67. I had the original 2 core rebuilt/upgraded to 3 core. This was to retain the original tanks and mounting as I found there is difference between the Chev and Canadian Pontiac rad mounting. The Canadian Pontiac uses a spacer where the Chev used the spacer as a shroud; changed the mount positions to where a replacement rad for a chev wont fit without modifying the mount points. My Parisienne is a 327 4bbl.
I haven't had any heat related issues since. I am only using the stock fan, no electrics.
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1967 Parisienne 327/glide 2 door sport coupe. In high school saved this from being crushed, restoration in 2010.
There are many things to consider when it comes to keeping the engine within operating temperature. The temp differential on your rad seems extreme. If its working that efficiently you wouldnt be overheating. I solved the high temp problem in my Beaumont by installing a shroud. The ZZ4 350 ran pretty warm before adding it.
I just got my 72 Nova on the road with a fresh 454 added. After consultation with one of the more knowledgeable members of Steves Nova Site I installed a 3 row, copper and brass big block rad. His calculations take into account the flow capabilities of 3, 4 and 5 row cores as it relates to their air flow and cooling efficiency. In his opinion, more rows is not always the answer. Also, a shroud and associated fan are key. Stay away from flex fans!
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72 Nova SS, 66 Beaumont Sport Deluxe, 09 Pontiac Solstice GXP Coupe
UPDATE: I flushed the radiator, run water through it until crystal clear. Must say that as I drained it the fluid didn't have any crap in it, it seemed pretty clean.
Drove the car today to work back in forth, combination of highway and city traffic, better than last time but not good enough. A friend of a friend offered me a shroud and found a place nearby that can convert my rad to a 3-core so I will consider both to solve the issue.
There is a really good radiator shop on the 520 highway near the 13, dorval radiator I believe. Its a one man shop run by a guy from France. He has done several rads for me, very happy with his work.
Before you start upgradingto bigger rads or fans or adding shrouds get what you have working right. Look at the rad inside or out for signs of rot or calcification (blockage), check the thermostat function and make sure your water pump isnt defective (impeller can rot reducing flow). The stock set up on your car was engineered to keep your engine at the right temp all the time.
520 is quite far for me but found a really good place on Industriel in Montreal-North. Got my 2-core rebuilt and problem solved. Temp doesn't get past 160° any more.
