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#1
10-01-2018, 08:22 AM
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'70 GP Heater Control Valve?
I'm a bit confused on this. Does the heater control valve on a '70 open or close with the vacuum? I show two Four Seasons part numbers # 74604 and a 74603, but which one is correct?
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30+ Years with NAPA. Happy to help with any auto parts questions. |
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#2
10-04-2018, 04:53 PM
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Good question, I'll check in my car tonight. You'd think you'd want the valve open (no vacuum) as a default for safety reasons (windshield defog-deice).
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My Break Away Squad 1969 Fbird (Base, 350 & Sprint Cvt’s - 400HO & TA Hardtops) 1969 LeMans (2dr & 4dr Hardtop and a Cvt) 1969 LeMans Safari 2 seat Wagon 1969 GTO (2 Cvt, 2 Hardtops & Judge Hardtop) 1969 Catalina (3 Cvt’s & a 2dr hardtop) 1969 Ventura 2 Seat Wagon 1969 Executive 4dr Sedan 1969 Bonnie Cvt 1969 Bonnie 3 Seat Wagon (2 of them) 1969 Bonnie Brougham (4dr Hardtop & Cvt) 1969 Grand Prix SJ (2 of them) 1969 2+2 2dr Hardtop (Canadian model) |
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#3
10-12-2018, 05:24 PM
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It is in full open at all settings ( vacuum applied) allowing coolant to pass.).. EXCEPT when at full cold.. then vac. is vented and the valve.is then closed.. according to the service manual...soo ..when vac. applied ( valve open) it will pass coolant...when vac. vented, or full cold..( no vacuum). valve closed.(no coolant passing)
Last edited by Forrest; 10-12-2018 at 05:41 PM. |
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