Scott's build of a 1981 CJ8 Scrambler
- Thread starter GraniteCrystal
- Start date
GraniteCrystal
New member
Maybe. See next post.
GraniteCrystal
New member
So did emissions test today. FAILED. Here is a pic of the screen. Anyone want to translate?
Guy said the carburetor is "running really rich" and taking care of that would help a lot. Also wondering if adjusting that will help it run smoother, particularly on the hills. Any how-tos on doing that?
Also said I need an air injection system and catalytic converter.
Sent from my Pixel using WAYALIFE mobile app
Guy said the carburetor is "running really rich" and taking care of that would help a lot. Also wondering if adjusting that will help it run smoother, particularly on the hills. Any how-tos on doing that?
Also said I need an air injection system and catalytic converter.
Sent from my Pixel using WAYALIFE mobile app
fiend
Caught the Bug
Carb running rich means the gas/air ratio is too high. Consider changing your jets to smaller jets (less fuel). Especially if you are at altitude, where the air is thinner. Also make sure you're getting good air flow (check air filter, etc.). Also pull and check your spark plugs. A rich condition will present as black sooty plugs or wet plugs If the plugs are fouled or partially fouled from running rich for a while, it just exacerbates your condition because you get insufficient ignition and more unburned gases coming out the tail pipe.
Brute
Hooked
Fuel injection?...
Your CJ is looking good...perhaps a carb rebuild & new jets...
Sent from my iPhone using WAYALIFE mobile app
WJCO
Meme King
Your hydrocarbons and carbon monoxide are your high readings. Hydrocarbon reading is basically unburned fuel coming out the tailpipe. A cat converter may be all you really need. An EGR valve may help as well. However first, I would ensure if the vehicle NEEDS to pass emissions for the year it was built. Most vehicles built after 1975 required a cat converter, do you know if this had one originally? There can be exceptions to basic emissions depending on how it was built. Also, any heavy black smoke coming out of the tailpipe when you rev it up?
Andy5160
Hooked
GraniteCrystal
New member
Cool. I'll check the end of the plugs tomorrow along with the rest of the air components.
I was quoted about 4k to convert it to fuel injection and I'm not sure if that make life easier or harder since that's now how it came from factory. Sounds like new jets are in order though.
Either way the cat converter has to go on. Emissions man said it doesn't matter if it came with one or not; every vehicle must now have one. Usually burns pretty clean but there are times when I think it's getting too much gas and the exhaust is more visible.
Thanks! I'm enjoying learning about it. Also looking forward to it running a bit smoother and being legal on the road.
WJCO
Meme King
Scott, a couple things to consider. I don't disagree with purchasing smaller jets to lean out the mixture, however, if it has the OEM jets in the carb now, it shouldn't be running abnormally rich, something else may be the issue. It could be as simple as an air delivery problem as well. If you get the engine too lean, you could do internal damage. So really make sure you do a lot of research with what you already have or what you decide to buy. Also, if I were you, I would buy a timing light and see where the timing is at just to make sure that is in check as well. It's cheap and easy.
Ddays
Hooked
$4k?!? No way I'd spend that kind of money on fuel injection. Holy hell you can buy a rebuild crate motor for less than that! Is the the guy maybe referring to an air injection pump that they used to run to help with the emissions? It'd be running off of the accessory belt if it's there. It's on the lower LH corner in this diagram.
Looked back in your thread and doesn't look like you have the air pump installed in this pic. It was pretty common for these to find their way to he dumpster bin back in the day.
Last edited:
GraniteCrystal
New member
Thanks Doug. Good point. I'll start with air. Maybe an easy fix there.
Yeah, I think it goes on the other side on this engine, but the air pump is missing. The bummer is that I can seem to find a new one online.
View attachment 272050
Looked back in your thread and doesn't look like you have the air pump installed in this pic. It was pretty common for these to find their way to he dumpster bin back in the day.
View attachment 272051
Based on what I know thus far, I think it goes on this bracket and there's an empty spot on the pulley system for the belt below.
Ddays
Hooked
Yup, looks like where it should go. Did you try Ebay? It looked like there were some there when I googled for images of the air pump. I didn't dig down into fitment but looked like there were plenty of options.
GraniteCrystal
New member
No, but good idea.
bigcale
Caught the Bug
Who told you it would be 4k for fuel injection? The Howell kit is only $1400 and the mopar kit is $2700(if you can find one for a manual trans, it looks like it was discontinued), there are other kits (I would not recommend them) on ebay for $1000. Unless you are paying someone to do the install that is way to high.
https://www.quadratec.com/products/17002_10D.htm
https://www.morris4x4center.com/mopar-multi-port-injection-conversion-kit-p5249686.html
If you want to be resourceful you could do what I did to my CJ7 and pull a complete head and injection system of a 4.0. Since the 4.0 is based on the 4.2 it bolts right on, that was the basis for the mopar system.
Last edited:
Gotta love states or counties that require emission testing. It's the only reason why I ended up selling my 81 CJ7 back when I was still in SoCal.
If Colorado only does a sniff test and does not have a visual inspection, you can do what's called a nutter bypass. Essentially, you can separate your Carter BBD from the computer (assuming you still have one) and dial it in yourself. Better still, if you're allowed to run an aftermarket carbs, I would recommend an MC2100. Great carb that will get the job done BETTER than the old Carter.
Agreed. Here's a write-up I did back in the day for the Howell TBI.
http://4x4xplor.com/TBI.html
GraniteCrystal
New member
Yeah, that was including installation.
I know the fuel injection is nicer and more practical but part of me just wants to keep it closer to stock. Am I crazy?
Again, if you don't have a visual inspection you have to pass, you should be able to lean out your Carter.
Also, just to make sure, you are running a cat, right?
GraniteCrystal
New member
There is a visual inspection as well. So I also failed on account of not having an air pump or catalytic converter. I was 90% sure I'd need those but wasn't sure and wanted to see what he'd fail me for. He didn't mention the EGR (or lack thereof) at all so not planning on adding that.
Just ordered an air pump from Pep Boys. Doesn't come with pulley though so I may have to source that from a junk yard. Or maybe there's a generic pulley I could buy? Pep Boys didn't show any options