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'86 3/4-ton Burb Smog

longbedder

longbedder

3/4 ton status
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Anyone have an emissions diagram (shop manual or underhood sticker) for the vehicle in the subject line?

Or an underhood picture of one that's smog legal in CA?
 
longbedder said:
Anyone have an emissions diagram (shop manual or underhood sticker) for the vehicle in the subject line?

Or an underhood picture of one that's smog legal in CA?
Click to expand...

Does it have EGR or not, and is it a CCC carb with ESC or is it just the regular HD 3/4 ton setup for 86?
I have the info for the non ESC.
I might have the other in my shop manual but I have to look tonight but my burb is non ESC
 
Thanks, guys. Here is the rundown:
I got it with the understanding that it would not pass smog visual, so it's on me to get it up to spec. There is no underhood sticker. I'm pretty sure it is not supposed to have ESC and the carb is mechanical.

I've got an EGR manifold that I'm going to put on it - my main question is how is the EGR valve vaccum routed (is there a EGR control solenoid, or a temp sensistive vacuum valve on the water neck)?

I also plan to put on a thermostatic air cleaner. It already has PCV, a charcoal can, and AIR pump.

It also has no cats - is that going to fly because it's 3/4-ton?
 
longbedder said:
Thanks, guys. Here is the rundown:
I got it with the understanding that it would not pass smog visual, so it's on me to get it up to spec. There is no underhood sticker. I'm pretty sure it is not supposed to have ESC and the carb is mechanical.

I've got an EGR manifold that I'm going to put on it - my main question is how is the EGR valve vaccum routed (is there a EGR control solenoid, or a temp sensistive vacuum valve on the water neck)?

I also plan to put on a thermostatic air cleaner. It already has PCV, a charcoal can, and AIR pump.

It also has no cats - is that going to fly because it's 3/4-ton?
Click to expand...

AIR with no cat doesn't really work, that is what I was told by my smog guy.
If you can give me your info he can look it up and tell you what parts you will need to have on there, also I can get you the vacuum diagrams and EGR stuff.
On my 3/4 ton HD PU I had no CAT and no AIR.
 
After some Googling, I did find this from a guy who bought the same vehicle I have new. I do have the TH400 tranny, also (this does factor in somehow, I'm sure). Perhaps my AIR pump is an add-on that was not original?

"The 1986 Chevrolet Suburban was the last to have a carburetor rather than fuel injection. The 3/4 in California was the last year not equipped with a catalytic converter. Both of these features (along with good quality workmanship) lead me to buy a 1986 K-20 4x4 Suburban in the first quarter of the 1987 model year. It has held up well. Anyone considering buying something to work on themselves, or to build a monster off-road vehicle should consider a Suburban from 1986. The stock transmission is the famous Turbo 400."
 
I went home and looked over lunch - it's 8600 GVWR. I stopped by one of the local shops, and they said it does need AIR, EGR, thermo air cleaner, charcoal can, but not cats.
 
I *suspect* the cat on a 3/4 ton is probably based on GVW, not necessarily just the 3/4 ton designation.

The emissions sticker will show both AIR if present, and will say "CATALYST" about dead center, top on the sticker.
 
That's my main problem - there is no sticker.
The local guy said based on GVWR of 8600, no cats but it must have EGR and AIR pump.
He didn't know (or look at a specific chart) to see how the EGR should be actuated.
 
Check autozones site, there have been at least two posts in the last months that linked to emissions stickers from there.
 
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