[gregneun]

I'm picking up a POS truck tomorrow, it's a 1977 Chevy C10 with a 350 in it. Got it cheap because it needs at least a head gasket.

Does anyone know the California smog requirements for this year. There's no CAT on this thing. I did not check the fuel filler to see if it had the smaller opening for unleaded gas nozzels. No smog pump or EGR either.

I'll ask the current owner on Monday. He was not there when we looked at it today.

Any info would be appreciated.

Thanks in advance,
Greg

[Ben M.]

Going to need the emissions sticker on the core support. That will tell you specifically what the truck *should* have, and the real check will obviously be what the computer itself that the smog tester uses specifically says it should have. I'd get the service manual for that year range and see what it specifically says too: here. Has the truck passed smog recently?

[gregneun]

I know a smog technician well and will have him look it up. I know they narrowed the emmissions a year or so ago. The law is that the seller is required to have the vehicle pass smog. This one needs some work and I know that.

It may have the emmision sticker on it, I'll look again tomorrow.

Greg

[steve25]

If it needs a head gasket ( the heads back then where very prone to cracking) it will also likly need a head , and if it needs a head due to over heating you might as well plan on changing out both heads with rebuilds as they are dirt cheap.
Wipe your finger in the tail pipe and check for oil coating as if you see a ridge in the cylinder when pull the one head on the blown side ten the thing is a oil burner, and at that point a whole rebuilt motor with a nice warranty would be the way to go.

[Cliff R]

Casting #882's were the staple from that period on the 350 engines, they aren't worth two squirts of duck poop for air flow, even on low rpm truck engines. Some came with #624's in 75-78, which flow slightly better, but I have never obtained a single set to date that wasn't cracked across the center exhaust valve seats.

I'm pretty sure GM was still using .020" steel shim gaskets in that period, so installing a much thicker head gasket will lower the compression about .3-.4, killing off even more power and making the engine even less efficient.

As for smog stuff, in the 48 states in 1977 even the 1/2 ton trucks under 6000 or so GVW did not use a CAT or air pump. Every year from 1978 to 1980 they extended smog to higher GVW's. In other words 1/2 ton trucks were good in 77, light duty may have had them in 1978, and 3/4 tons were good in 79, but got the CAT's in 1980. One ton trucks finally got CAT's in 1981.

I'm pretty sure California was at least one year ahead of the 48 state emission stuff.

Going by memory here, but I'm pretty close on the dates and GVW ratings. 1977 will be close for seeing emissions stuff on 1/2 ton trucks. If it's a light 1/2 ton, it probably had a CAT from the factory, and most likely EGR and Air Pump.

I'm not even sure where one could find the correct information specifically for your truck and GVW rating, but I'd start with a Google search, or talk to a tech where they do emissions testing.........Cliff

[Keith Seymore]

1975 was the first year for cats on a 1/2 ton pickup.

Here's the generic info packet from the GM Heritage Center archive. It will show what option content was available in this model year.

K

http://www.gmheritagecenter.com/docs...olet-Truck.pdf

[gregneun]

My apologies for asking about an off brand vehicle here, Pontiac didn't make a trucks so I hope the disappointed will pardon me on this. There's more info available to me here than I have and I thank those that contribute.

I wish it was smog exempt, it's not and I'll have to deal with it, even if it needs a different engine. Between the junkyard, smog guy and mechanic I hope to make it work.

Thanks again,
Greg

[geeteeohguy]

Got the 2013 Mitchell Emission Control Application Guide right here. (I am a licensed CA smog tech). Your truck needs PCV, ACL (thermostatic air cleaner), EVAP (evaporative fuel system charcoal canister/hoses), OC (Oxidizing Catalytic Converter), FR(Fillpipe restrictor), EGR (Exhaust gas recirculation), AIS (Air injection system), and EFE (early fuel evaporation(heat riser). The cost of getting and installing all of this equipment if it is missing may well outweigh the cost of getting the truck repaired. It is all required to register your vehicle. If you want to get around the Smog Check program, you need a '75 or older truck. Good luck.

[grrrrregg!!!]

Originally Posted by geeteeohguy

Got the 2013 Mitchell Emission Control Application Guide right here. (I am a licensed CA smog tech). Your truck needs PCV, ACL (thermostatic air cleaner), EVAP (evaporative fuel system charcoal canister/hoses), OC (Oxidizing Catalytic Converter), FR(Fillpipe restrictor), EGR (Exhaust gas recirculation), AIS (Air injection system), and EFE (early fuel evaporation(heat riser). The cost of getting and installing all of this equipment if it is missing may well outweigh the cost of getting the truck repaired. It is all required to register your vehicle. If you want to get around the Smog Check program, you need a '75 or older truck. Good luck.

quick ?, all cars from 75 and on are smog exempt.

['ol Pinion head]

In '77 & 78 one could buy a Big 10 or Heavy Half (GMC) pickup that was basically a 5/8 ton. Those two years, on that level of pickup, there was no cat convertor or EGR valve on the intake. My dad special ordered a new '78 shortwide Silverado Big 10 with the LM1 350 & after my brother got it in '81, we upgraded its performance with 186 casting heads, cam, headers, duals w T/A splitters, a built turbo 400, 3.40 gears, & an HO Racing power kit for the Q-jet.

Besides looking for the original GVWR decal, one can look at the rearend. The '77 & 78 Big10's originally will have the 12 bolt truck rear. The lower GVWR standard half tons those two years had the 8.5 corporate 10 bolt. In '79, the Big 10 & Heavy Half were still avail, but there was a restrictor in the gas tank filler neck & a cat convertor under the truck.

[Ben M.]

Originally Posted by grrrrregg!!!

quick ?, all cars from 75 and on are smog exempt.

1975 and earlier are all smog exempt. 1976 and newer have to pass. Naturally you can't modify the emissions equipment of anything that is smog exempt, wink wink.

[zeebo]

Originally Posted by Cliff R

Casting #882's were the staple from that period on the 350 engines, they aren't worth two squirts of duck poop for air flow, even on low rpm truck engines. Some came with #624's in 75-78, which flow slightly better, but I have never obtained a single set to date that wasn't cracked across the center exhaust valve seats.

I'm pretty sure GM was still using .020" steel shim gaskets in that period, so installing a much thicker head gasket will lower the compression about .3-.4, killing off even more power and making the engine even less efficient.

As for smog stuff, in the 48 states in 1977 even the 1/2 ton trucks under 6000 or so GVW did not use a CAT or air pump. Every year from 1978 to 1980 they extended smog to higher GVW's. In other words 1/2 ton trucks were good in 77, light duty may have had them in 1978, and 3/4 tons were good in 79, but got the CAT's in 1980. One ton trucks finally got CAT's in 1981.

I'm pretty sure California was at least one year ahead of the 48 state emission stuff.

Going by memory here, but I'm pretty close on the dates and GVW ratings. 1977 will be close for seeing emissions stuff on 1/2 ton trucks. If it's a light 1/2 ton, it probably had a CAT from the factory, and most likely EGR and Air Pump.

I'm not even sure where one could find the correct information specifically for your truck and GVW rating, but I'd start with a Google search, or talk to a tech where they do emissions testing.........Cliff

yup..882's..ugh..just wanted to let you know that of the two trucks i have--a 1976 chevy 1/2 ton 2wd with a 350, it had a converter, and my 1979 3/4 ton 2wd suburban did too--i cant remember the criteria for what trucks did/didnt come with egr or converters, but i do remember my buddies dads old 1975 gmc heavy half with a 350 4bbl had no egr and no converter--i know cuz i removed the double hump trans crossmember for my 79 suburban..

[zeebo]

Originally Posted by 'ol Pinion head

In '77 & 78 one could buy a Big 10 or Heavy Half (GMC) pickup that was basically a 5/8 ton. Those two years, on that level of pickup, there was no cat convertor or EGR valve on the intake. My dad special ordered a new '78 shortwide Silverado Big 10 with the LM1 350 & after my brother got it in '81, we upgraded its performance with 186 casting heads, cam, headers, duals w T/A splitters, a built turbo 400, 3.40 gears, & an HO Racing power kit for the Q-jet.

Besides looking for the original GVWR decal, one can look at the rearend. The '77 & 78 Big10's originally will have the 12 bolt truck rear. The lower GVWR standard half tons those two years had the 8.5 corporate 10 bolt. In '79, the Big 10 & Heavy Half were still avail, but there was a restrictor in the gas tank filler neck & a cat convertor under the truck.

thanks for the info--my 76 half ton 2wd pickup has the 3.40 12 bolt axle, and my 79 suburban 2wd 3/4 ton has the 14 bolt 3.73 rear.

[gregneun]

Thread got moved here and I still want to thank all for their input. Cliff is right on with the 882 heads and exactly where the crack is. The GM historical link is terrific and I would not have found that myself. OPH, damn, where do you pull the info from? Great sources all.

Now that the A-kissing is done, it's actually a relief to find the cracked head. Figured it was the gasket and that looked fine. In the dark we could not see the crack. For now I'll need a head, or set, get it running and go from there.

Turns out it was grampa's truck, the fenders are dented, but for now it'll be fine. Body and box are in good shape, as is the wood bed floor. The oak needs some linseed oil.

I don't feel bad that I originally posted this in the street section. What's a guy supposed to do for an old truck? Maybe PY should have a POS truck section.

Thanks again,
Greg

[gregneun]

It's alive!!!!

Found a set of rebuilt heads on CL for $100, painted the the heads and intake, Pontiac metallic blue, installed everything and away it goes. Drained the oil/water mixture from the crankcase. Runs nice and shifts fine.

It's a long bed, step side, wood bed unit and I got it for $1000, both rear fenders need work, rust free SoCal truck. They sell repop fenders, but I'll scour the junkyards until I find both.

The smog guy looked it up and said the emmissions were lax and it should pass smog, original equipment is there. While title transferring at AAA they gave me the last 4 smog check history and it passed, dating to 2006. The tags are due in June, so if I delay the smog check, maybe i won't have to retest in a couple of months.

Again, thanks for the info. When I bought it, I needed info and knew PY would be a good source. Apologies offered to the moderators and any that were offended that I posted in the "Street" section. There's no traffic here, so I did what I felt was best. Sometimes I think there is a little too much brand loyalty. I mean circumstances do arise and there is no truck section.

Take care,
Greg