Northstar Engines and System Technical Discussion Discussion, 1998 Eldorado - DexCool mix in Cadillac Engine Discussion; Today I plan to change my coolant. I know that you're not supposed to "flush" the system, but one thing ...
Today I plan to change my coolant. I know that you're not supposed to "flush" the system, but one thing that concerns me is the fact that DexCool has been mixed into my system with regular green coolant. I didn't know that you weren't supposed to mix the two until after I had done it. The car had regular green coolant in it when I bought it. What should I do (if anything)?
Automobile(s): White Diamond '03 DHS (with DTS floor shift)
Re: 1998 Eldorado - DexCool mix
I'd just drain it and refill it. What little is left shouldn't hurt anything. I did the same thing many years ago to a '96 Bonneville. Just drained and refilled it and ran it to 185K about a year and a half ago. Never had a problem. No reason to panic.
Drain the coolant and run some fresh water through the system - garden hose and some care not to get much, if any, water on engine or braking components. If you really get dedicated you can use a shop vac to pull/blow most of the residual water from the block and heater circuit. Use a 50/50 mix of whatever type coolant you like - just change it every 3 years or so. A total refill will take a couple of warmup/cooldown cycles to purge the air bubbles from the system - use the FULL COLD arrow on the top and side of the coolant reservoir - about half full, cold.
Cool, thanks. I drained and refilled. I put a tube of powdered Alumaseal in the upper radiator hose since the parts store didn't seems to have Bars Gold.
Why ?? Did you have nuisance leaks before you did the coolant exchange ?? Those sealants run the risk of clogging small head gasket water passage holes as well as the (aluminum) heater core.
The correct sealants originally installed by GM and discontinued in ?? 2002-2003 ?? were Bar's Leaks #DHC tablets or G12BP powder. 3 tablets crushed, or 1/2 tube of powder, in the bottom radiator hose.