fjc-man
SILVER Star
Jim, and everyone else out there. This thing helps alot. Made by Hitchmate, 50 bucks.
Failed Emissions high CO with ABV vented (02 into exhaust stream), passed 5K miles ago
- Thread starter Infinity00
- Start date
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I’ve always known you were a smart man Bill. You know I’m not tall and something like this sure would beat the 5 gallon bucket I normally use. Worse than that is the bruise I get on my chest from leaning over the top of the fender. I suppose a 5” lift doesn’t help my cause…
To save my back, I've got to get one of these engine bay creepers:
fjc-man
SILVER Star
Wow, the Cadillac! Mine is not this cool, but it folds up and you can bring it with you.
Really ? I'd never seen one like that. Much prefer being able to fold and store. What brand?
fjc-man
SILVER Star
Hitchmate, it’s ajustable for tire size and platform can be adjusted up and down.
Ah, ok - the one for the tire. Cheers.
- Thread starter
- #28
It's failing almost identically to before!
Digging through old JimC threads all day looking for anything related to idle mixture starting points at altitude and rejetting and lo and behold, I found my old failed smog writeup and fix.
Thread TL
R
I changed out carb with another diy rebuilt one I had, but I also added cruiser outfitters thick gaskets around the carb base and around the middle insulator. I added the bushing to the dizzy, where the original had disinegrated, to take care of the issue with too much advance, I left the HAC hooked up creating around 13 deg of advance before retarding the dizzy a little (didn't say how much), Lean drop performed but then enrichened to 13.5, replaced plugs that were fouled (again!), new air filter. Later, in the carb I was struggling to get working right, I found a small bit of debris in one of the jets that wouldn't come out until I used a #12 guitar string to push thru it.
Lastly, and maybe importantly, after I passed I added a lighter spring to the secondary to get it to open (it wasn't opening before that). I might just put the original spring back on - ensuring the secondary doesn't open! And I've been contemplating putting my spare carb on it since the current one sat for the better part of the last 1.5 years while I sorted the smog out (putting all the smog components back on after being desmogged for 5 years) and prepped it for sound deadening
Digging through old JimC threads all day looking for anything related to idle mixture starting points at altitude and rejetting and lo and behold, I found my old failed smog writeup and fix.
Thread TL
RI changed out carb with another diy rebuilt one I had, but I also added cruiser outfitters thick gaskets around the carb base and around the middle insulator. I added the bushing to the dizzy, where the original had disinegrated, to take care of the issue with too much advance, I left the HAC hooked up creating around 13 deg of advance before retarding the dizzy a little (didn't say how much), Lean drop performed but then enrichened to 13.5, replaced plugs that were fouled (again!), new air filter. Later, in the carb I was struggling to get working right, I found a small bit of debris in one of the jets that wouldn't come out until I used a #12 guitar string to push thru it.
Lastly, and maybe importantly, after I passed I added a lighter spring to the secondary to get it to open (it wasn't opening before that). I might just put the original spring back on - ensuring the secondary doesn't open! And I've been contemplating putting my spare carb on it since the current one sat for the better part of the last 1.5 years while I sorted the smog out (putting all the smog components back on after being desmogged for 5 years) and prepped it for sound deadening
Last edited:
- Thread starter
- #29
Passed. Thanks for the support!
New plugs
New air cleaner
New oil
CO down to 29 limit is 45
New plugs
New air cleaner
New oil
CO down to 29 limit is 45
- Thread starter
- #30
For those of us at altitude I forgot I had this little tool from Mikuni. I’m not sure I’m using it exactly right, but it looks to me like I should put a 140 into the carb at my altitude andwork up from there to see if it helps keep the plugs from fouling.
That’s very interesting. I see the point of going up or down in size, although many vehicles have systems built in to compensate for elevation. So if you installed the jet appropriate to your elevation (according to this sheet), then the HAC would make you far too lean. It’s a dance.
- Thread starter
- #32
Good point! I’ll plug the carb inlets when I put the smaller main jet on
Or let the stock system work. Just sayin'...
Worst case, leave it stock, see what the AF does, and go from there. I think I mentioned above I have a 25cc VTV (smallest size) on the main air feed hose running from the HAC to to the carb. There are three lines from HAC to carb that all feed air, but one in particular seems to be doing most of the work, especially over a certain rpm. The VTV cut my highway cruise A:F from about 17.5 down to 15-16. I would suspect that at altitude you would have a lower AF reading in the same condition because there's less oxygen in the air.
If it ain't broke don't fix it.
- Thread starter
- #34
It is broken. My plugs are fouling!
Then fix the stock system!
How much oil is the truck consuming?
- Thread starter
- #37
It’s not stock. Rebuilt engine with oversized Chevy valves and shaved head, one size up on pistons. No oil consumption that I’m aware of.
