Vacuum system issue

[jbstephens]

1976 Chevy c10, carb has been rebuilt by Uremco, 350 v8, 2 barrel Rochester carb, I broke the three port valve on the thermostat housing. Where do I find a new one, also need a diagram to hook up vacuum lines, owned by the same family since new, thanks

 

[Terlingueno]

What color is the plastic part of the switch?

 

[DoubleDingo]

Check the reference library here, there's a lot of vacuum sticker diagrams posted up, there might be one that matches yours or closely matches it. The links may be broken, so you'll have to navigate to the post by going to whatever page and post# it says. Years ago the links worked, not sure if staff has gone in and fixed them.

 

[jbstephens]

it is all metal , no plastic, appears to have been red or orange at one time, has the number "676" stamped on it

 

[75gmck25]

Rockauto usually has the most complete listing for this type of part. You can also just search there for the number 676, but you might get too many hits because it’s such a common number.

 

[jbstephens]

thanks for the tip

 

[75gmck25]

It may be a PVS76 ( note the “S”not a 5). However, I only saw them listed on eBay, so maybe they are discontinued. You might be able to cross-reference it to a newer/replacement part.

https://www.ebay.com/itm/146383565236

 

[awar]

The three line vacuum switches usually were manifold vacuum to distributor when cold and changed to ported vacuum when warm. Are you just trying to keep it original or are they still smog checking a 50 year old truck? My 72 Camaro was a California 350 2v and had that switch. The only time that it was connected was for the yearly smog checks. I ran the distributor on ported vacuum the rest of the time. It also had an electrical vacuum switch to block vacuum advance except in high gear. That also was “bypassed” 364 days a year.

 

[DoubleDingo]

The three line vacuum switches usually were manifold vacuum to distributor when cold and changed to ported vacuum when warm. Are you just trying to keep it original or are they still smog checking a 50 year old truck? My 72 Camaro was a California 350 2v and had that switch. The only time that it was connected was for the yearly smog checks. I ran the distributor on ported vacuum the rest of the time. It also had an electrical vacuum switch to block vacuum advance except in high gear. That also was “bypassed” 364 days a year.

Dang, they really dislike(d) you, making you test annually, usually it's biannually

 

[awar]

California in the 70s. We left in 1980.

You must be registered for see images attach

 

[jbstephens]

not trying to keep orginal, no emmissions testing for the old of a vehicle. I put a plug in the top of the thermostat housing instead of the ported valve, choke and heat don't work correctly

 

[Ricko1966]

1976 Chevy c10, carb has been rebuilt by Uremco, 350 v8, 2 barrel Rochester carb, I broke the three port valve on the thermostat housing. Where do I find a new one, also need a diagram to hook up vacuum lines, owned by the same family since new, thanks

Some underhood pics would be a good idea. I'm thinking you broke the egr efe thermo vacuum switch. And pics would also help us identify what else may be wrong and causing your problems.