new radiator
Thread Starter
Racer
Joined: Sep 2001
Posts: 374
Likes: 0
From: Rochester NY --- FL (Oct to May FL.)
new radiator
I put in a new Dewitts alum radiator and while the hood is off fecided to relace the engine harness wiring. I'm almost done and now wondering if there is a technique to filling this radiator since you can't just remove the cap & refill while it's running.
Thanks for any help
Thanks for any help
Tech Contributor
Joined: May 2005
Posts: 15,576
Likes: 118
From: Conroe Texas
I filled the engine in my 65 at the overflow tank. Once that tank was about 1/2 full, I started the car and opened the heater valve to let the water flow everywhere it needed to go. Then I topped off the overflow tank to the 1/2 mark and that was it.
Race Director
Joined: Jul 2002
Posts: 11,593
Likes: 173
From: Clayton NC
I put in a new Dewitts alum radiator and while the hood is off fecided to relace the engine harness wiring. I'm almost done and now wondering if there is a technique to filling this radiator since you can't just remove the cap & refill while it's running.
Thanks for any help
Thanks for any help
Instructor
Joined: Jan 2006
Posts: 156
Likes: 0
From: Boerne Texas
just replaced my 63's radiator
I removed the copper/brass unit that was in the car when I bought it and replaced it with a DeWitt unit. Car runs about 10-15 degrees cooler now.
As to filling. I simply filled through the expansion tank. You should see the level in the tank drop as the fluids make their way around the circuit. Once the level in the tank appeared to hold, I figured I was pretty close to full. I fired up my car with the cap off of the expansion tank. I turned on the heater and let the car idle keeping a close eye on the level in the expansion tank. After topping off a few times, the level seemed steady so I put the cap on and took the car for a spin. After a 10 minute drive, I let the car cool and checked the level. All was okie dokie. Not sure if that is the right way to do it, but it worked for me.
As to filling. I simply filled through the expansion tank. You should see the level in the tank drop as the fluids make their way around the circuit. Once the level in the tank appeared to hold, I figured I was pretty close to full. I fired up my car with the cap off of the expansion tank. I turned on the heater and let the car idle keeping a close eye on the level in the expansion tank. After topping off a few times, the level seemed steady so I put the cap on and took the car for a spin. After a 10 minute drive, I let the car cool and checked the level. All was okie dokie. Not sure if that is the right way to do it, but it worked for me.
Team Owner
Joined: Oct 2000
Posts: 38,897
Likes: 1,926
From: Washington Michigan
Just to clarify, there's no "heater valve" on any midyear (unless it has factory A/C); water flows freely through the heater core at all times, regardless of the position of the heater controls. 
Instructor
Joined: Jan 2006
Posts: 156
Likes: 0
From: Boerne Texas
JohnZ is right, as always.
I forgot to mention the heater valve bit. If you are AC free, then you need not worry about running the heater. My car does have a heater valve, so I had to turn the system on to be sure the fluid was making it's way there.
Melting Slicks
Joined: Mar 2004
Posts: 2,397
Likes: 35
1. Fill with thermostat housing off. make sure to use correct thermostat housing gasket from GM. A little gasket sealer also help preventing leaks and won't show if done properly.
2. Fill expansion tank 1/2 way.
3. Run to operating temperature.
4. Check exapnsion tank level when done - goal is 1/3 to 1/2 fill.
2. Fill expansion tank 1/2 way.
3. Run to operating temperature.
4. Check exapnsion tank level when done - goal is 1/3 to 1/2 fill.
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Tech Contributor
Joined: May 2005
Posts: 15,576
Likes: 118
From: Conroe Texas
Team Owner
Joined: Oct 2000
Posts: 38,897
Likes: 1,926
From: Washington Michigan
If you use the newer GM thermo housing gasket (#10105135), you don't need any sealer - that gasket has a silicone seal ring molded on both sides, but looks exactly like the original after it's installed.
Le Mans Master
Joined: Jul 2003
Posts: 6,808
Likes: 24
From: Westport CT
As for filling my cooling system, I confess I simply remove the end of the upper rad hose that attaches to the t-stat housing, bend it up slightly, and jam a 90 deg funnel in that end and fill it into the top of the rad. Little hole in my t-stat burps the air through there.