coolant flush question

[titanium10k]

Im about to do a drain and refill of my dexcool and I was wondering if anyone removed the engine block drain plugs and if so where are they located???thanks

[TonyMazz]

Consider taking it to a dealer where they can do a real good backflush of the heater core. Simple, clean and correct.....

 

Much easier, effective, and timely to have them do it....

[kdm101]

The plugs are on the rear of the block below the #7 and 8 cylinders. You'll probably have to go underneath to actually see them.

 

As far as going to a dealer, I see no problem with doing this yourself. I am planning on doing it soon myself along with replacing hoses and can't see spending roughly $200 on just the flush on a fairly simple procedure.

 

Now, the official GM coolant flush procedure in the manual doesn't state anything about removing the drain plugs. However, if you do pull them out, the manual does state in another section that when replacing, apply a bead of sealant (GM #12346004 or equivalent - dunno what it really is), and tighten to 44 lb ft.

 

The flush procedure in the manual basically states to fill the system with water, run the engine up to temperature (ensure the thermostat is open), drain, and repeat until it's pretty much clear. My Haynes manual says to pull the thermostat out and run a garden hose through the upper radiator inlet and let the water flow back out the upper hose until it's clear. I think both would work fine. GM says to never use a chemical flush. I plan to go the route of removing the thermostat since I plan to replace it anyway, and it should be faster (no having to waste time with heating the engine up and letting it cool between fill/drain cycles).

 

Oh, and be sure to turn the heater control to HOT in either case.