coolant color?

I just had the water pump replaced on my 93 SL1 and the coolant
refilled (not flushed) after an overheating incident. But looking at
the new coolant, it appears dirty and gray (not brown). There is a
gray sludge on the surfaces of the tank. It doesn't smell like oil,
but it's hard to be sure. There is no evidence of a head gasket leak,
and so far the car's cooling system appears to run normally during both
interstate and local driving.

What do those coolant pellets look like after they're dissolved? Is it
possible that the shop added these and they just weren't added before,
when the coolant appeared uniformly clear and green for years?

Or can refilling a system that has never been flushed before stir junk
up (especially after overheating)?

Trying to decide whether to get a flush. Thanks.

 

i also have a 93 sl1 w/183k , when i canged the water pump i flushed out
the cooling system,changed all hoses,cts,ects,thermostat,new anti
freeze,and belt,if i was you i'd have it flushed out and see if it changes
color again.
good luck.

 

What coolant type did they use? Did they add the "brown" tablets?

My opinion is that it really should have been chemically flushed and
completely rinsed afterward before refilling with new coolant, especially
after the overheating incident coupled with being a couple years past due in
the first place.

Bob

 

I have no idea if they added tablets. Well, I'll just go have it
flushed tomorrow, it looks really dirty. I don't know how to ensure
that the correct coolant and sealant pellets are added, or if they even
should be added (saw a post on this group saying that Saturn dealers
don't sell the pellets anymore, and that with the new Dexron coolant
doesn't need it, but not sure if this is good info. When I added
coolant previously, just used phosphate-free ethylene glycol as
specified by the manual...)