Overheating in traffic... Should I worry?
There are only two things in life that will make me run for the hills faster than Jesse Jackson chasing a $20 bill and that's snakes and flex fans. Flex fans always scared the crap out of me, spinning razor blades.
I have now been enjoying the vette over the summer, on long drives, stopped in traffic, bumper-to-bumper stop-and-go, and everything is fine.
Then a couple of weeks ago, I discovered a leak from the radiator. Both sides. Just a gentle drip, nothing dramatic, but enough to need a new rad.
Who was it that said that "on a 50 year old car, things break just because?" :-)
I checked all the hoses, and they're fine, so I really need a new one. Which means another big order across the pond. Always nice to have an excuse to order some other stuff...
With the help of my local garage guy, we tried to pour in some "Radiator Fixer" liquid, but that did nothing, and we had some fun with backpressure and lots of coolant spilling everywhere. Good times.
Anyway, car is running nice and cool, I occasionally add a bit of water (the constant leaking adds up), but it's all good.
Diagnosing Corvette Overheating
ALL diagnosis of Corvette overheating MUST begin with pressure testing the cooling system. If it isn't holding pressure, then all the electric fans and Water Wetter and, and, and, and, in the world isn't
going to cure it. Key is don't lie to yourself; if that pressure tester needle moves AT ALL in 30 minutes, you've got a pressure leak. Find it and fix it.
Order a today. Best $80 you'll ever spend.
A single drippy hose clamp is all it takes.
It works like this; if your cooling system is holding pressure, you almost can't do anything wrong. Car just doesn't overheat. Hot days, cold days, uphill, downhill, stuck in traffic, 70mph
If it isn't holding pressure, you can't do anything right. No pusher fans, additives, sealers, shrouds, timing or mixture changes, thermostats, turning the heater on, anything will fix it.
Do NOT remove the thermostat or run a 160F thermostat attempting to cure your overheating. Reportedly, you will lose gas mileage, power, AND probably foul your plugs.
If you don't have all the foam pieces FORCING air through the Corvette radiator, and not over it, around it, under it, order a kit and install it.
A 50/50 mix of distilled and coolant is all you need. PLUS a working radiator pressure cap, and overflow bottle/hose that IS NOT CRACKED OR LEAKING.
Quit staring at your temperature gauge all the time! Quit making excuses for it: "Well it only overheats WHEN...... "
Get your cooling system sealed up and start enjoying your Corvette!
Last edited by wadenelson; Oct 2, 2021 at 04:42 PM.
- Either a flow cooler or Stewart stage 2 waterpump
- 180 degree T-Stat
- Water Wetter
- Flush radiator thoroughly
- Ck timing, try advancing to at least 10
- Make sure all seals around the shroud are in and closing extra air.
Better but not beaten.
In the end I swapped out the copper and brass radiator for an aluminum. Presto problem solved.
You didn't list "hook vacuum advance can to manifold vacuum ONLY. Having ported/timed vacuum on that can...or having NO vacuum advance at idle will make it almost impossible to run cool.
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