Chevy & GMC Vans

HI, I'M A NEWBY TO THE FORUM AND WANTED SOME HELP ON FLUSHING MY COOLANT ON 2002 ASTRO, I CAN'T FIGURE OUT WHAT HEATER HOSE IS THE INLET OR OUTLET, PLEASE HELP.

PETER

Hi Peter........Welcome to the site. It doesn't really matter which one you use. Either one will flush the engine. Remove the lower radiator hose and let the water run until it comes out clear.

THANKS FOR THE FAST RESPONSE, I WANTED TO USE A PRESTONE FLUSH KIT AND IT SPECIFIES WHAT HEATER HOSE TO TAP, ALSO WHILE I'M ON IT WHAT COOLANT CAN YOU RECOMMEND. 2002 ASTRO

PETE

Welcome Peter!

Please lose the caps lock.

IIRC, the inlet hose is the one that hooks to the intake manifold, and the return hooks to the pump on the suction side. I hope I have that right.

If you run the heater on a cold engine, you can feel the hotter hose as the engine warms, that is the inlet.

This is how I did mine, it is the only really good way if your van had Dexcool in it, IMHO. viewtopic.php?f=6&t=5199&start=0

PLEASE don't use a Prestone Flush Kit. Cutting a line gives you one more place for a leak and the cold water from the household water supply will cause the t-stat to stay shut.

Hey, welcome to the forum! Great people here with lot's of help. I agree, scrap the flush kit.
Just unhook each hose and jam a garden hose in and blast away, works great. If you really want to flush the whole system, unhook any and every hose and flush both forward and back. I think you'll find this cheap, easy and effective. Doing it even just once should last a long time before any need of it again.

Thanks a lot, I will let you know how I make out.

Pete, 02 Astro

CaptSquid wrote:the cold water from the household water supply will cause the t-stat to stay shut.

stupid question perhaps.... can you pull the stat and then flush it with cold water? .. or when run, if the cold water warms up anyway .. wouldn't the stat open?

curious

The Capt. is correct. Cold water will keep the t-stat closed. However, if you flush through one of the heater hoses the t-stat will not affect the flush provided the heater hoses are connected to the manifold and water pump. In order to flush the radiator you will have to remove the radiator hoses.

If you're doing the flush, this would be a good time to spend $5 and replace the stat anyway, good insurance.

LaGrasta wrote:If you're doing the flush, this would be a good time to spend $5 and replace the stat anyway, good insurance.

+1

crash wrote:

CaptSquid wrote:the cold water from the household water supply will cause the t-stat to stay shut.

stupid question perhaps.... can you pull the stat and then flush it with cold water? .. or when run, if the cold water warms up anyway .. wouldn't the stat open?

curious

Sorry, crash, but the water flowing through the engine isn't in there long enough to get warm. I did that on a 77 DJ5 and only managed to flush part of the system. It NEVER got warm.

I went to the hardware store and got the metal hose ends and a few worm clamps. I kept them in my tools until I got rid of the old girl (the N. Charleston PD took her away because they CLAIMED I was parked illegally. They hated sailors.)

FYI-be careful about putting 40 degree water into a 150 degree engine. Sometimes physics wins.

That sounds SCARY . Care to share the details?