replacement type of anti freeze?

[Duke W.]

Re: replacement type of anti freeze?

Duke------


For Corvettes, knock sensors began with the 1982 model year.

Thanks, I had no idea knock sensors showed up that early on any car. My 1988 MBZ and '91 MR2 don't have them.

Duke

[Joe L.]

Re: replacement type of anti freeze?

Thanks, I had no idea knock sensors showed up that early on any car. My 1988 MBZ and '91 MR2 don't have them.

Duke

Duke------


The 1982 knock sensor, GM #1997463 aka Delco 21-388, was, as far as Corvettes go, unique to 1982. Other knock sensors were used in following years. The 1997463 is long-since GM discontinued and you don't want to need one.

[James W.]

[Joe L.]

Re: replacement type of anti freeze?

Just finished changing the coolant on my ‘64 and ‘65. I had neglected doing this for over 8 years which could be the reason I had to replace my original radiator in my ‘64 with a new one from Dewitts. I Could not get the block drain plugs out on either car. I repeatedly flushed the system with distilled water, went through probably 12 plus gallons of distilled water at $0.74 per gallon. I would drain & refill the cooling system and then take the car on a 10 mile drive on the interstate and run the engine at 3,000 rpm or more to get the water to thoroughly circulate through the block, then come back and drain it. Repeat until it ran relatively clear. I then filled with Zerex G05. Final freeze point protection is - 30 to 35 degrees F.

James------


I think you went way "overboard" on this unless your tap water has really high total dissolved solids (TDS). If you can't get the block drains out, then what I recommend is to install a Prestone "flush-and-fill" kit. Using it, you can easily flush your cooling system. After the flush, you drain at the radiator and, based on your cooling system capacity, add enough concentrated coolant to get your system to the desired percentage (50% for most, 60% for me), and top off with tap water (or, distilled water if you choose). With the flush-and-fill kit you will need to install the flushing "T" in one of the heater hoses. If you wish, you can just replace that hose after the flushing or, if you don't mind the appearance, just leave it. And, yes, this can be done even in a Corvette with external supply tank; I've done it myself.

You should be able to obtain an annual water analysis report from your water supply agency. I believe it's an EPA requirement that they provide you with one. Let us know what TDS the report shows and I'll be able to tell you if it's too high to do this.

[James W.]

[Joe L.]

Re: replacement type of anti freeze?

Joe,

I don’t mind spending the small amount of money on the distilled water. If always used it and always will. Omaha’s water is very hard. Just replaced some shower heads and sink faucets do to deposits.

Thanks,

James

James------


It's not the cost of the distilled water that's the problem. It's all the effort involved in the flushing that you described mostly due to not being able to remove the block drains. The "flush-and-fill" kit I described will give you a better flush with a lot less effort. However, if you have very hard water, that's a problem. Something you could do is to obtain a mixed bed DI cartridge and use it to flush with the "flush-and-fill" kit. This will likely cost more than the distilled water but the flushing will go much easier and, likely, better. The mixed bed DI cartridge will produce water equivalent to the distilled water.

[James W.]