Author Topic: Vacuum Diagram 1977 GMC K10  (Read 21840 times)

Offline Lt.Del

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> Re: > Vacuum Diagram 1977 GMC K10
« Reply #15 on: February 14, 2006, 11:36:00 PM »
If your area requires emissions testing, you gotta ensure the vehicle you purchase is up to the test or you'll be spending $$$$.

I don't know what the year range for when gm had egr valves.  I just know my 79 had 'em.  

To have an EGR, your intake must be an EGR-type intake, or you can't even put an egr on it.  There should be hole under your carb on the intake on right side w/ two bolt holes.  Some modified engines may have this blocked off.  However, some previous owner may have swapped intakes and an EGR will never go on it.  When you order an intake, one must specify EGR or not. When i ordered my new 383, I specified that I am keeping all the smog stuff on it and wanted an intake w/ EGR.  I could be wrong but I think it is the edelbrock performer intake 2901, for some reason that number sticks in my head.  I bought a new EGR when I put the motor in my truck.

If someone stripped your engine in the past, they could have taken all that smog crap off of it, therefore, you wont have the TVS, EGR etc....



Edited by: SgtDel at: 2/14/06 11:40 pm

Offline 83silverado

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Re: > Re: > Vacuum Diagram 1977 GMC K10
« Reply #16 on: February 14, 2006, 11:31:00 PM »
Looks like that's what happened here.  My manifold does have a place in the top of the thermostat housing for a TVS, but no hole in the front of the manifold for the other one in your pictures.  I also do not see a place for an EGR valve, not even anything blocked off.

Maybe a lesson learned, since I did not even think about emissions when I bought the truck.

Offline cooltoolguy

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Re: > Re: > Vacuum Diagram 1977 GMC K10
« Reply #17 on: February 15, 2006, 07:01:00 AM »
no cats, thats not good,   here in Jersey you show up with out those, and they check, instant impound and a hefty fine I believe last i check was a few grand max.  gotta watch the road side checks too by the troopers.

Offline adamrx7

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Re: > Re: > Vacuum Diagram 1977 GMC K10
« Reply #18 on: April 03, 2006, 09:43:00 AM »
UPDATE, My truck runs great now!!! Thanks for the help guys. Truck starts on first crank!!!

Offline 77Bonanza

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Smog check?
« Reply #19 on: April 04, 2006, 12:04:00 AM »
No emissions checks here in Arkansas for now.  We haven't even had annual inspections since 1997.  

I was glad too see them go at the time.  I didn't think they accomplished much.  Now I see lots of vehicles without brake lights, busted windshields etc...