Cooling system leak on TBI

So I get to come home from vacation to a car down with a coolant leak. On the Auto climate control TBI cars there is a heater control valve under the hood that attaches to metal pipe fittings and molded metal to rubber connectors. Guess where it's leaking....

MY quick fix (when the motor cools down) is to is to bypass with a tube to hose from the rad and the one to the block, but in about 3 months when it gets cooler out and we don't need max AC at all times (like we do now). I wanna fix it.

Curious if I'm going to have to bite the bullet on what looks like a dealer part, or are there other options around....

I have a used one available. The junk yard has them occaisonally if you are patient. They are usually broken, but if you get there before the gremlins, you can find a good one.

If you carefully cut the metal clamps with a dremel, and a cutoff wheel, you can use hose clamps.

thanks Fred. I know I have a set of 9C1 hoses from a TBI but I don't think it has the vacuum valve that the Auto climate control has....Have to dig them out this weekend. I cut the hose coming from the rad to the tee, pulled the piece of hose from the block off the top of the valve (recently replaced it when I broke the stupid vacuum valve last year) and took a 6 inch piece of copper water pipe and four hose clamps for now. About to go pic the boy up from school so we'll see if the four hose clamps can hold it together with out a barb on the ends....


this morning I filled it and lost over a gallon on a 25 minute drive to go get my work truck.....

If you need another valve, I do not have current plans for the spare I have.

it's not the valve but the metal plumbing below the valve.....temp solution is holding so I'm good until November when it's gets cooler out. WHen I get some time I'll pull it off and see where it's leaking from....

Sprocket;
I know this is an old thread, but I had the same problem on my L05 Caprice earlier this year. First time it blew, I just replaced the plastic vacuum valve.

But the second time, I decided not to mess with all the cobbled up connections and looked for an OEM replacement, including the tubing.

That part was available in the aftermarket from AC-Delco. I had no problem finding one. It's pricey, but it worked perfectly. It came with the fittings to attach to the heater core tubes; no leaks, no problems.

It's still available on RockAuto for $67 plus shipping.

ACDELCO Part # 155404 {#10100979}
VALVE,HTR WAT FLOW CONT w/o SE0 SILICONE RUBBER HOSE(1T1)



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