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Hello,
We took delivery of our 1976 Corvette on Monday and have been looking into various things.
The PCV has a visible break in the seal, however when we try to search for this part, we are only seeing them with one hose coming out of it where the one currently installed has two.
Please see photo.
Any ideas on why this part was used and how we can proceed with a single hose type?
Thank you. We've been searching, noticed it was broken and a friend said it was the PCV, we are too green to know better.
More research ahead.
Thanks again.
If it's the same as a 77 and I think it is that switch is called EGR TVS switch to the EGR valve. There should also be a thermo switch in your thermostat housing. This thermo switch is called EFE TVS switch and also have 2 vacuum lines to it with a exhaust port so it will have 3 ports (lower port open).
76-77 EGR TVS Switch part Number 3031385. Replacement switch Standard Brand part number PVS71
76-77 EFE TVS Switch part Number 355962. Replacement switch Standard Brand part number PVS43
L48 PCV valve Number is CV-774C Any auto parts store can cross these numbers.
L82 PCV valve Number is CV-775C
Diagram for a L48 1977:
Any ideas on why this part was used and how we can proceed with a single hose type?
That would be your EGR TVS switch, or thermo-vacuum switch which routes from the EGR to the TVS and onto the carb. So a leak is probably vacuum-related given what can be seen from the photo. The 76 AIM listed GM #3031385 which will help a parts manager track down a service replacement. I've found replacements through Dr. Rebuild.
I see Joe already listed the parts and their replacements. Gotta love those colored emission hose schematics!
Last edited by hunt4cleanair; Jul 8, 2019 at 12:36 PM.
PCV valve with two hoses?
