How many Gallons of coolant do I buy??

[bigtim44]

I'm going to change out the coolant in my 102A3 when I put in the block heater,How many Gallons of antifreeze do I need to buy to refill.Going to use the Rotella ELC.

Tim

[gumpy]

Well, I just did mine (6v92). Before opening the engine preheat loop, I put in 10 gallons of coolant and 6 gallons of distilled. water.  When I opened up the preheat loop, I added another 2 gallons of antifreeze and another gallon of water for a total of 19 gallons. That was a little light on the antifreeze. Only good down to -25, and the next morning when I found that a new hose had leaked 3 gallons out over night    I added 2 more gallons of antifreeze and another gallon of water. 

Oh yeah, there was 2 qts of DD Powercool in there, too. 19 1/2 gallons total with the preheat loop. 16 1/2 without it.

So, on a 6v92 with cold weather protection (50/50), I'd recommend buying 12 gallons of antifreeze, and 6 gallons of distilled water.

Oh, one other thing, this formula is good when you've flushed the entire system and rinsed it all out so there's only water in the heater cores. If you're not flushing the system, then I'd buy 9 gallons of antifreeze and 9 gallons of water and mix 50/50.

craig

[DavidInWilmNC]

Without sounding too ignorant, how does one tell if the correct antifreeze is in the cooling system?  I have a hose I need to replace which will require draining both radiators and the expansion tank.  If it's the incorrect type, I'll flush it and change it all out, including the heaters and associated plumbing.  If it's correct, I'll just save what comes out and reuse it.

David

[Eagle]

You can purchase test strips from your local Detroit Dealer.

[Ncbob]

David, you can buy an anti-freeze hydrometer at most auto parts stores.  Beware of the cheap ones. Or if you know a diesel mechanic who owns  a refractometer that's the best way to test anti-freeze or battery solution for charge.

My advice: If you're going to own an expensive engine in weather which might freeze the system...invest in a refractometer.  It's the best investment you'll ever make.

NCbob

[Dallas]

David,

Whenever you get down here again, I'll let you use my refractometer.

As Bob says, a refractometer is (about) the only accurate way to test antifreeze or battery acid.

Dallas