98 Chevy Suburban K2500 Cooling system questions

I have a 1998 Chevy Suburban K2500 4x4 (7.4L gas) with 117k miles. The radiator developed a crack in the oil cooler tank right beside the upper oil cooler fitting. So, it was time to replace the radiator -- and while I was at it the water pump, thermostat and upper/lower radiator hoses.

Before starting the work, I check the coolant level and it was at the top of the radiator neck. The coolant resevoir was empty (some coolant lost due to the leak). When I drained the radiator, I checked the amount of coolant collected and it was approx 2 gallons. After removing the radiator and the radiator hoses, I removed the water pump. I then removed the coolant drain plug on the passenger side of the engine and about 2.5 gallons of coolant came out.

I then removed the drain plug on the driver side of the engine --- maybe 2 drops of coolant came out. So at this point, I only have 4.5 gallons of coolant. The capacity of the cooling system is 27.5 qts -- so now I am wondering where the rest of the coolant is and why didn't any coolant drain from the driver side of the engine. Some coolant did of course spill on the ground in the process -- but not that much. Even if 1/2 gallon made it to the ground, there is still quite a bit of coolant hiding somewhere.

I noticed that the coolant was still pooled at the driver side water pump port. The passenger side water pump port is empty. I have a picture at :

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-- just select the "Radiator work" pdf file. Note: the coolant appears green because I had previously added some dye which changed the Dexcool color from red to green.

Questions

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- Should there have been coolant draining from BOTH drain plugs ? The GM service manual just says remove the drain plug -- doesn't even mention (in the text or diagrams) that there are two.

- Since there is obviously still coolant sitting on one side, does this basically mean I have a blocked coolant passage ?

I would prefer to remove all the old coolant -- I could put everything back together and flush with water. But I'm concerned about the coolant not draining from the one side.

Any ideas or suggestions are greatly appreciated.

Thanks

Reply to
cr
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Take that driver's side plug out again, get a screwdriver and stick up there and knock the rust loose, and prepare for a green shower. :-)

-- Old Crow "Yol Bolson!" '82 FLTC-P "Miss Pearl" '95 YJ Rio Grande BS#133, SENS, TOMKAT, MAMBM

Reply to
Old Crow

I tried that (gently) initially with no success. I spent about an hour today trying different wires, screwdrivers, ice pick, etc with no luck. I could get some really small pieces out but nothing major. It feels very solid - so apparently it has not been flushed properly in the past. I purchased the car used with about 98k miles on it.

Not sure how else to get it cleared out without using a drill, etc. Unfortunately, being on the driver side right above the oil filter, there is not much room there. I may not have a choice but to put everything back together and just flush out the old coolant that is left.

Thanks for the help.

Reply to
cr

Pressure washer might work if you have one, or one of those dryer lint brushes or even a soft brass brush from a gun cleaning kit.

Reply to
azwiley1

The heater and hoses hold about three quarts:

With both plugs out, and a pan underneath. Lift the rear in the center, and some should come out.

Make sure the thermostat housing is off, and the thermostat out.

You'll never get the whole 27.5 quarts out anyway. That is the capacity as estimated by the engineers, fully assembled and bone dry.

I hope this helps.

Reply to
Refinish King

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