Coolant recommendation?

[Paul Higg]

Can anyone recommend a good anti-freeze? I have to replace the coolant sensor and it will require draining the coolant. Any particular brand?

Thanks.

Paul

94 LT1

 

[Toms007]

Paul, I used the premixed Prestone stuff last winter when I replaced the water pump, optispark, and seals on the front cover of the engine. Says it will mix with any and all "flavors" of antifreeze. Have you purchased a set of Helms (factory service manuals)manuals? Not inexpensive up front, but priceless when you go to these maintenance items. I bought mine off Ebay used.

Oh and I suppose you do know not to get the Opti wet? They don't like being wet and will have a tendency to puke on you if it does.

 

[Paul Higg]

Thanks Tom, I have the entire FSM and it is a LOT to read and digest. Presently I am tying to learn how to troubleshoot an intermittent chime problem and a SYS light. I have the SYS light narrowed down to whenever I cover the ambient light sensor with my finger it comes on every time. Easy to duplicate but when I look in the FSM, to get access to the CCM or the chime unit, well, it is NOT for the faint of heart. You have to tear the whole car apart!

By the way, what on earth is the optispark?

Only had it a month, first Vette. 94 coupe LT1.

 

[Toms007]

Thanks Tom, I have the entire FSM and it is a LOT to read and digest. Presently I am tying to learn how to troubleshoot an intermittent chime problem and a SYS light. I have the SYS light narrowed down to whenever I cover the ambient light sensor with my finger it comes on every time. Easy to duplicate but when I look in the FSM, to get access to the CCM or the chime unit, well, it is NOT for the faint of heart. You have to tear the whole car apart!

By the way, what on earth is the optispark?

Only had it a month, first Vette. 94 coupe LT1.

The optispark is the "distributor" on the LTx series engines. It is mounted directly to the camshaft on the front of the engine.....right underneath the water pump. Not the best location for something that doesn't like water/antifreeze. To replace it the WP has to come off. If you have a WP go out (starts leaking antifreeze) while you are in there you may as well replace it because it's on borrowed time anyway. Oh and change the wires then as well, they are a real pain (not impossible, just a pain) to get at with the WP in place.

 

[Paul Higg]

Thanks Tom but good grief, could GM have made it any more difficult for a mechanic to work on this car? Were they a bunch of sadists or did they try to discourage ordinary folk to spend money at the dealer?

 

[Toms007]

I don't think they could have made it much worse. I actually had all that apart last winter, once I got started it wasn't that bad, just pretty intimidating at first. With your back ground this should be a piece of cake.

 

[Paul Higg]

I'm sure I could do it, just a lot of cross referencing in the FSM on what to remove in what order. The only problem is this is our only car and it would put us out of commission. We are planning on buying my wife a car hopefully soon.

 

[Toms007]

I'm sure I could do it, just a lot of cross referencing in the FSM on what to remove in what order. The only problem is this is our only car and it would put us out of commission. We are planning on buying my wife a car hopefully soon.

Yea that would put a damper on things. I'm lucky in that the wife has her car and I have a pickup.

 

[Red Vette]

I put the Prestone antifreeze in my 94 instead of the red or green. If you go that route as Tom says, may sure you get the one that says "will mix with any antifreeze", otherwise the old antifreeze reminants in the system after flushing will not be soluble in the new antifreeze and could cause problems. The Prestone should be good for 100K miles, but keep an eye on it as you do all of your fluids.
I noticed that Tom has an new Avatar - it looks great Tom.
Barrett

 

[Paul Higg]

Thanks for the tip Barrett. I never knew there were so many anti-freeze options. Especially the "will mix with any other kind."

 

[Red Rocket]

I'm thinking of changing the coolant as well once the weather warms up. I've picked up a few good tips from this thread but am wondering what the best method is for draining and refilling the system. I was simply going to pull the rad hoses from the rad, let it drain, flush with water then refill.

 

[Paul Higg]

I just read the FSM yesterday and it is like any other car. Open the pet cock at the bottom of the radiator with the radiator cap off, let it drain, have someone hold a garden hose in the radiator fill hole till the radiator is full, start engine and let it run till the water flows clear out of the pet cock.

There is a warning though, monitor coolant temperature. If it gets too hot, I forget right now what the temp was shut off the engine and let it cool completely and repeat with the garden hose till it runs clear.

Then close the pet cock and refill with a mixture of anti-freeze and water. NOT pure anti-freeze, the freeze zone on pure is -8º F, with water I think it is -34º F.

Make SURE the pet cock at the bottom of the radiator is closed, how many other guys have wasted a gallon of anti-freeze by forgetting to close it? I'll admit I did it ONCE, that's all it takes.

Paul

 

[air1jpg]

I'm thinking of changing the coolant as well once the weather warms up. I've picked up a few good tips from this thread but am wondering what the best method is for draining and refilling the system. I was simply going to pull the rad hoses from the rad, let it drain, flush with water then refill.

Red,

Since you have a 1996 model, your car has the newer orange anti-freeze in it. The anti-freeze in your car shouldn't have to be changed until you reach 100k on the clock. '96 was the first year GM put the new anti-freeze in the Corvette.

 

[Red Rocket]

Thats true about the 100,000, I've only got 57,000 on the clock. But the anti-corrosive properties in the stuff are supposed to break down after 5 years. With all the aluminum in there I'd like to keep the corrosion to a minimum. The guy I bought the car from last fall owned it for 5 years. He never replaced the coolant, so its been in there at least 5 years. I was going to use the Prestone product.

 

[JAKE]

This anti-freeze question has come up often on other forums too. From all I've read, many guys are emphatic NOT TO MIX ORANGE AND GREEN anti-freeze, saying the mixture of the two won't, AH, mix.

As to which one to use, virtually all those who responded to this issue recommend the GREEN anti-freeze, BUT IN ORDER TO USE IT THE ENTIRE COOLING SYSTEM MUST BE THOROUGHLY FLUSHED, INCLUDING THE HEATER CORE.

When I built my new engine last year I opted to stay with the ORANGE, not wanting to introduce yet another variable into the mix. Even though the engine was new, the hoses and heater core still had residual ORANGE in them.

Jake

 

[jsinga]

I'm with jake.
If the car came with green use green or one of the universals. If it came with orange put orange in it or completely flush it and put something else it. I have read hours about coolant and am still not clear. All I will say without reservations is don't put Dexcool (orange) in anything it didn't come in. No other OEM will touch Dexcool with a 10ft pole but GM won't let go of it, they are a bulldog about it.
Coolant doesn't wear out. The anti corrosion package is used up. Most of the chain shops just recycle the stuff. They have a filter system and dump more additives in the tank every once in a while.
If I had a LT car with opti spark I'd spend time a little money to do all I could to make sure crud didn't eat the water pump seal and trash the opti

JS