Radiator question

[Coach James]

here's my situation. I have a 2002 Grand prix that uses Dexcool. Recently, my temp gauge would occassionally fluctuate up and down from 180 to 200 degrees where it did not do this before. I checked the radiator and I have brown gunk in it which I'm sure is the result of Dexcool possibly running low.

My questions are: Is this fluctuation harmful?

When I flush the radiator this coming weekend do I need to use distilled water to do it? I use distilled when I add water but don't know if I have to use it for a flushing.

And has anyone used the green "add to any color antifreeze" antifreeze yet?
Thanks
Coach

BTW, I hate Dexcool!

 

[Tim240Z]

I did a reverse flush (power flush) to my L31 Vortec to get rid of all traces of DexCool. Then I refilled with distilled water and green coolant.
Here is a good article on power flushing. I used it and it worked great.
http://www.pacificp.com/forum/viewtopic.php?t=1202&highlight=radiator+flush

 

[kartracer55]

Lemme ask ya this... Is it just slightly discolored or is it almost like a mud? Can you see it building up inside the filler neck? When was the last time you changed the coolant? Usually a brown muck indicates the cooling system wasnt maintained.

GM has been using the redstuff for a little while. Apparantly guys have had problems with this but thats what GM calls for so I wouldnt switch to Ethelyne glycol or the propylene? Glycol. Its generally not a good idea to mix the stuff either because of chemical reactions which can cause corrosion and rust. Keep it all the same, if your in a jam, add water... not a different anti-freeze.

Id get it flushed then refill with the specified type.


Just my .02


Jim

 

[OctaneMotorsports]

To flush use a 50/50 mix of distilled water and distilled vinegar.

Drain the old stuff, pour the new stuff in, run it for a few minutes, drain, fill with coolant.

 

[eschoendorff]

I just did a water pump on my wife's 1998 GP. That Dexcool is know for causing brown muck/mud. It was all over in the recovery tank and at the very top of the radiator neck. Oddly enough, the water pump and the water jacket passages in the block were nice and clean. Your fluctuations may be coming from some of that muck that has lodged itself in the water jacket somewhere. A good flush should help this....

My wife's car doesn't fluctuate that much, but with the change in weather, I do notice it a little more. Also remember that GM screen prints those analog gauges onto the dash panel and that they are notorious for not telling the complete truth. They are not well-calibrated. On teh C4 Corvettes, most of us go by what the digital temp gauge says, rather than the analog. BTW... both the digital and analog gauges on the C4s get their data from different sensors. The digital sensor is located right in the water pump and is usually ragarded as the more accurate of the two. I do not know if this applies to the GP, but you may not want to get overly worried about your GP if the gauge is showing between 180-200*. I think that the fans are programed to come on around 230-236* or something anyway. Now, If your car starts to spike or get into the red area, then you can worry.

You can also go here to do a little more research on GPs:

http://www.clubgp.com/newforum/default.asp?cookieCheck=478863808

 

[AndrewM]

My wife's 99 Montana had the brown sludge build up in it due to DexCool. I hate the stuff, I won't run it in any of my vehicles. When I replaced the intake manifold gasket (after the dealer tried twice, and it kept leaking), I flushed completely and went back in with the Prestone metro stuff (it swings both ways, orange or green ).

Apparently air is 'bad' in a dexcool system, and it seems that the V6 engines just don't get along. My wife's is a 3.4L V6, but I've heard the same thing from the GP folks (above) and the S10 folks.

I'll run the green stuff or metro stuff, but never again with Dexcool. NEVER again.

 

[oldskewl61]

yea fluch it out switch to green lable it well though so no one puts in dex-cool they dont get along (something about pics of ones wife or some thing HA HA)