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7/9 Updated Heater Control Valve

This morning I got out the digital caliper and measured the OE valve and OE hose I.D. Nipples on OE valve are 16 mm (5/8") and the OE hose is 15.46 mm.
 
This morning I got this valve installed. One problem, the valve leaks at the flapper shaft lever. But only in the closed position. Turn the heat on and it quits leaking. The valve is in new condition, not even dirty yet.

I looked on some Astro Van forums and learned that several Astro Van owners have been having the same problem. Their solution: remove valve, replace with 2 pipes, and plug vacuum hose.

Looks like I need to put the pipes back in in place of the valve. Too warm outside to drive with the ECC temperature control turned to 85.
 
I found another bypass valve that's temperature controlled instead of vacuum. GM part number is 22657309 (15-5675). Fits:
Chevy Cavalier 99-02
Chevy Malibu 99
Olds Alero 99-01
Pontiac Grand Am 99-01
Pontiac Sunfire 00-02

http://www.autoplicity.com/products/1792597-gm_performance_22657309_valve_asm_htr_wat_bypass.aspx

Another bypass valve that I found was GM 15688297 (15-50572) fits 90-95 Chevy Astro Van. It's made just like the vacuum controlled valve with the exception of it being temperature controlled (it contains a metal spring and a plunger and no vacuum servo).

I have a temp controlled Bypass valve from a Pontiac Grand Am installed at this time.
 
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Only thing with that valve Lummert is there's no vacuum control. The 7/9 series don't control the temp thru that valve, but rather via a blend door setup. The normal HVAC controls provide an on/off to allow or stop coolant thru the core, that's it. How are you planning to control the flow thru that valve to shot off the coolant flow? Just curious.
 
Sounds like he's using it for the bypass of your valve while retaining the Volvo valve for the heater control, possibly eliminating the failure prone GM part perhaps?
 
gsellstr said:
Only thing with that valve Lummert is there's no vacuum control. The 7/9 series don't control the temp thru that valve, but rather via a blend door setup. The normal HVAC controls provide an on/off to allow or stop coolant thru the core, that's it. How are you planning to control the flow thru that valve to shot off the coolant flow? Just curious.
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I've considered this. I'm working on a way to pressure test the valves to check for coolant leakage before installing on car. I have 5 or 6 of the vacuum controlled Chevy Astro Van heater bypass valves. One of them is bound to be leak free.
 
mafoose said:
Sounds like he's using it for the bypass of your valve while retaining the Volvo valve for the heater control, possibly eliminating the failure prone GM part perhaps?
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The pressure controlled bypass valve would be a good idea if I can find room to also fit in a manual shut off valve between the bypass valve and the heater core.

I have a cable operated valve from a 1980 VW Dasher in my stash.
 
vxracer said:
This is great! I recently had the plastic nipple break off and spew coolant till near overheat. Lucky I was going downhill on the highway with an exit at the bottom with a gas station there:cool:! So I just cut the motor off.. Then a quick water fill for a 1/4 mile to auto store.

I recommend to everyone to carry a 5/8 x 2" double nipple or even a piece pipe in the trunk for an easy 5 minute hose bypass. Or be stranded. I slapped another unit from a pick n pull back in, but I have the piece I purchased in the trunk with a water and a coolant jug. Till I can sort it put.

This new unit may be the way to go. I'm glad I waited to do this job now!

Nice work! Thanks.
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The plastic 3/4" barbed (1 angled barb at each end) hose connectors I found on a Chevy Astro Van were 4 inches long.
 
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After figuring out how to hook up a vacuum controlled Astro Van heater valve to the water pipe for my shower (minus the shower head) I found that all 4 of the valves in my pile leaked. I then tried the pressure controlled Astro Van heater valve with the VW/Audi cable operated valve installed in place of a heater core. With VW/Audi valve open water flows through the Astro Van valve. VW/Audi valve closed the water by-passes the core.

This arrangement will work fine after getting both valves installed on the car. Just need to install a push/pull control cable for the VW/Audi valve. The same car that donated the valve still has the diesel injection pump advance cable installed. I can try to use that.

VW/Audi heater valve: 171819809E. Available from NAPA for $5.40, used from 1975 to 1993 on VW/Audi cars.
 
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gsellstr said:
Just my .02 but it seems like that's more money and work involved than just grabbing new valve, toss it in, and be done with it.
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At the moment I'm just experimenting on what works. I have more time than money. I can say that the pressure controlled by-pass valve in line with the VW/Audi heater valve does work. A good Volvo vacuum controlled valve would work good with the pressure controlled by-pass valve.

There is room to run the pressure controlled by-pass valve and the VW/Audi valve in-line with the hose from the head to the heater core. Then the return hose returns through the bypass valve.
 
The Astro Van heater control valve can be taken apart for repair. It's just an o-ring that needs replacing to fix a leak.
 
gsellstr said:
Problem with that is it is vacuum modulated, rather than closed with vacuum as the stock one is.
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I'll check this out. I tested a good used valve with water pressure and a hand operated vacuum pump. The vacuum seemed to do it's thing.

Checked out the valve with the vacuum pump. Takes only 5 inches of mercury to start pulling the valve, 8 inches of mercury and the valve is completely pulled. Between 5 and 8 inches of mercury modulates the valve. No vacuum results in coolant passing through the heater core. Vacuum applied and coolant bypasses the heater core.
 
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So, bad news on the heater valve front. Went to replace the radiator after an end tank started leaking, found a small puddle under the firewall. Seems as though the end tank went and the heater valve went as well. Not a critical failure, just some seepage, and oddly enough, not from the shaft, but rather one of the end caps.

Grabbed a new one from oreallynow, time will tell how it does.
 
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