Split window heating problem
Thread Starter
Racer
Joined: Jan 2004
Posts: 277
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From: Bellevue WA
Split window heating problem
My split window is running normally as long as the temperature is below 70. Once it gets above that, it starts a run toward the peg. It goes up slower on the highway but still creeps up. In traffic it's dead meat. I've had the radiator flushed, cut antifreeze to about a fourth, added a couple of packages of water wetter and put on a seven blade fan. The fan clutch seems to be all right in that it only turns three or four blades when the car is freshly shut off and the thermostat holds the car at 180 during cooler weather. It does have a 15 PSI radiator cap rather than the prescribed 13 PSI so I will change that but what am I missing? The car is virtually original ('64 master cylinder) so I don't particularly want to put an electric fan on if I don't have to.
Appreciate the help.
Stick.
Appreciate the help.
Stick.
Le Mans Master
Joined: Jan 2002
Posts: 8,913
Likes: 283
Re: Split window heating problem (Stick)
What is your timing set at, and what type of dist/ignition are you running?
Have you checked the gauges to be sure it is accurate? Compare it’s reading with that of a Infrared Temperature gun.
How old is the radiator?
Mark
Have you checked the gauges to be sure it is accurate? Compare it’s reading with that of a Infrared Temperature gun.
How old is the radiator?
Mark
Thread Starter
Racer
Joined: Jan 2004
Posts: 277
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From: Bellevue WA
Re: Split window heating problem (ghostrider20)
I'm not sure of the timing but it's the original distributor with electronic ingnition. It was also doing this before changing to electronic ignition. I assumed the gauge is all right because it consistently measures in line with outside temp. Wrong assumption? The radiator is brass and about ten years old and 3-4000 miles total. I just read that with the original aluminum radiator, the radiator cap is 15 PSI rather than what the shop manual calls for (13 PSI). I would wonder which one is correct with a brass radiator and the aluminum overflow tank...
Le Mans Master
Joined: Jan 2002
Posts: 8,913
Likes: 283
Re: Split window heating problem (Stick)
Quote
“The radiator is brass”
I don’t think that any SWC’s were equipped with a brass radiator. I think they made their first appearance in the BB cars. The Brass radiators are inferior to the Aluminum 316 model. The heat transfer/rejection rate is considerably less so the margin of efficiency regarding deterioration is slim. In a nutshell your radiator was marginal at best when new.
The timing issue should be addressed and verified with the shop manual for your engine.
I would put money on the brass radiator capitulating to age and normal blockage.
If this problem came on with the change to the electronic ignition, make sure your timing is set and the recommended base setting and the vacuum advance module is operating to specs.
I recall Duke mentioning that with the SHP 63-64 motors the vacuum module should be switched to the 8” unit that arrived on 65 SHP motors.
Mark
“The radiator is brass”
I don’t think that any SWC’s were equipped with a brass radiator. I think they made their first appearance in the BB cars. The Brass radiators are inferior to the Aluminum 316 model. The heat transfer/rejection rate is considerably less so the margin of efficiency regarding deterioration is slim. In a nutshell your radiator was marginal at best when new.
The timing issue should be addressed and verified with the shop manual for your engine.
I would put money on the brass radiator capitulating to age and normal blockage.
If this problem came on with the change to the electronic ignition, make sure your timing is set and the recommended base setting and the vacuum advance module is operating to specs.
I recall Duke mentioning that with the SHP 63-64 motors the vacuum module should be switched to the 8” unit that arrived on 65 SHP motors.
Mark
Thread Starter
Racer
Joined: Jan 2004
Posts: 277
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From: Bellevue WA
Re: Split window heating problem (ghostrider20)
Thanks for the quick reply. I should have said that it currently has a brass replacement radiator for the original aluminum. It had been done when I got it. The change happened before the electronic ignition but I'll check it out to be safe. Thanks for the tips on the IR temp gun (didn't know there was such a thing) and the vacuum module switch. You helped a lot and I appreciate it.
Le Mans Master
Joined: Jan 2002
Posts: 8,913
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Re: Split window heating problem (Stick)
For your case, stop by a shop or find a friend with an IR gun as they are around $100.00. I am obsessed with tools, much like the sickness women have with shoes so I had to have one.
Tom Dewitt is a regular around here and builds a correct replacement for your application. I am not sure the price. For a few extra frog skins I think he offers a correct stamp and dated model if that concerns you. In regard to radiators they are expensive, but what on a corvette is cheap.
There are few things I like to be a slave to and an unstable car is not one of them. If found to be the problem, bite the bullet and install a 316. If maintained, it will last for as long as you own the car.
By the way, what motor option is in you SWC?
Mark
[Modified by ghostrider20, 12:17 AM 4/12/2004]
Tom Dewitt is a regular around here and builds a correct replacement for your application. I am not sure the price. For a few extra frog skins I think he offers a correct stamp and dated model if that concerns you. In regard to radiators they are expensive, but what on a corvette is cheap.
There are few things I like to be a slave to and an unstable car is not one of them. If found to be the problem, bite the bullet and install a 316. If maintained, it will last for as long as you own the car.
By the way, what motor option is in you SWC?
Mark
[Modified by ghostrider20, 12:17 AM 4/12/2004]
Thread Starter
Racer
Joined: Jan 2004
Posts: 277
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From: Bellevue WA
Re: Split window heating problem (ghostrider20)
Good idea. I have some sources for the IR gun. I looked them up on the internet and they range from $25-$150. The $25 one looked pretty cheesy and was recommended for taking the temp of reptiles. Guess it will only work on a Viper... my motor is the 340 horse L76. The car is riverside red with black interior four speed.
Thanks again.
Thanks again.
Race Director
Joined: May 2000
Posts: 12,712
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Re: Split window heating problem (Stick)
How often was the antifreeze changed? A ten year old radiator could be clogged up with deposits if the antifreeze wasn't changed every couple of years even with low mileage accumulation.
All '63s had a 13 psi cap as OE, but later models with the same cooling setup have 15 psi caps. Retrofitting a 15 psi cap to a '63 is SOP.
What are the numbers on the vacuum advance? Does it work? If it's the original can it should be replaced with a NAPA/Echlin VC1810.
Duke
All '63s had a 13 psi cap as OE, but later models with the same cooling setup have 15 psi caps. Retrofitting a 15 psi cap to a '63 is SOP.
What are the numbers on the vacuum advance? Does it work? If it's the original can it should be replaced with a NAPA/Echlin VC1810.
Duke
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Team Owner
Joined: Oct 2000
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From: Washington Michigan
Re: Split window heating problem (SWCDuke)
The RayTek Minitemp MT-4 is available from many on-line sources for about $75.00 - here's one of them:
http://www.toolsource.com/ost1/raytek/
:cheers:
http://www.toolsource.com/ost1/raytek/
:cheers:
Thread Starter
Racer
Joined: Jan 2004
Posts: 277
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From: Bellevue WA
Re: Split window heating problem (SWCDuke)
I flushed the radiator last summer but that was the first time in a while so I think you and ghostrider20 have centered on the cause with the brass radiator. My bad. I'll leave the 15 PSI cap in place and I'm on my way to pick up a VC 1810. I really appreciate your help.