1977 Blazer

[noco-k5]

I am thinking about buying a 1977 Blazer. It's a California truck and I'm located in Colorado. Does anyone know what emissions equipment it would have had originally. I've done a search on this forum and others and there are a lot of different opinions. It only has to pass a two speed idle test here, but I'm more concerned about the visual inspection. Some things I've read said 77's had minimal emissions while others indicate they have smog pumps, cats, etc. Any clarification would be appreciated.

[ray_mcavoy]

Originally Posted by noco-k5

Some things I've read said 77's had minimal emissions while others indicate they have smog pumps, cats, etc. Any clarification would be appreciated.

When it comes to required emissions equipment in these years it all depends on the vehicle's GVW. I believe it was 6000 lbs for 1977. Anything 6000 lbs and under was considered "light duty" and basically had all of the same emissions equipment as a 1977 passenger car. Anything 6001 lbs and above was considered "heavy duty" and only had minimal emissions equipment.

The info kits available from the GM Heritage Center at http://www.gmheritagecenter.com/gm-h...tion-kits.html have tables in them that list all of the emissions equipment that would have originally been on a particular engine.

UPDATE ... I just took a look at the 1977 Blazer info kit and that one doesn't appear to have the emissions equipment table ... but it is in the 1977 pickup truck info kit.

And according to the Blazer info kit, the 2wd's were rated at 6050 lbs GVW and the 4wd's were 6200 lbs GVW so that puts them in the "heavy duty" emissions bracket. It also shows that the only two engines available in the 77 Blazer in California were the 350 and 400 V8's.

Looking at the emissions tables in the 77 pickup info kit under the "heavy duty" column shows both the 350 and 400 were equipped with:

Federal = PCV (positive crankcase ventilation), CCS (controlled combustion system), and CHA (carburetor heated air).

California = PCV, ECS (evaporative control system), TRC (throttle return control), CHA, and AIR (air injection reactor).

[jlmerie]

I also live in Colorado. I have a 1978 GMC short bed truck. It is a 2 wheel drive and rated at 6050 GVW. Last time I was at the emission testing station for my Jeep, I talked to the station manager about what emission equipment I needed for the 78 GMC. We concluded almost nothing was needed. NO catalytic converter was needed. The truck also did not have any designation for unleaded gas. That is the fuel gauge in the dash did not say "Unleaded Gas" and the gas filler tubes did not have the unleaded restrictors. I agree with Ray that the cutoff for heavy duty was 6000. The fellow I talked to got out his reference books and confirmed this information for me. I have to believe the emisions would be about the same as 1977. Certainly 1977 would not be more restrictive.

[noco-k5]

Thanks for the feedback. I think I'm going to pass on the Blazer. It's really nice, but I don't want to pay to ship it out here and then get stuck with a bunch of emissions repairs. Think I'll try and find something closer to home.