Weber carburetor and high altitude

[manitou]

The '83 CJ5 I just acquired has a Weber 32/36 DGEV (electric choke). I was wondering if anyone out there has had problems when it comes to high altitude on a temporary basis. I guess what I'm asking is...can I drive my cj from 1,000 feet elevation to 6,000 feet on one day; then to 14,000 the next day; then back down to 6,000; then 1,000...all without making a lot of adjustments to the carb? In other words, is it feasible to take my cj on a vacation to Colorado if it's tuned to Missouri? Thanks for any help/advice!!

 

[Neuner]

Sorry I'm not going to be of much help but you're bringing back a lot of memories from when I moved from Missouri to Colorado quite some time ago.

I had an early FI system then and it seemed like it took it a little bit to figure out where it was and what it needed to do to perform at the higher elevations. There are quite a few who are better at answering this but after recently reading up on calculating carb CFM req'ts, I'm assuming you will be running fairly rich at those altitudes. I have that carb and I think the only way to change this is by changing the primary jets.

 

[manitou]

Thanks Neuner! We'll be moving out to Colorado in seven years (God willing), and I plan to keep my cj...so I'm sure I'll have to convert to FI at that time, if I haven't already. When I was a kid, we used to go to Colorado a lot. As soon as we'd pull into the Springs, my dad would stop at a gas station and have them make a temporary adjustment to the carb. I was hoping it would be that easy with the weber, but I don't think so.

 

[Fastatv]

Thanks Neuner! We'll be moving out to Colorado in seven years (God willing), and I plan to keep my cj...so I'm sure I'll have to convert to FI at that time, if I haven't already. When I was a kid, we used to go to Colorado a lot. As soon as we'd pull into the Springs, my dad would stop at a gas station and have them make a temporary adjustment to the carb. I was hoping it would be that easy with the weber, but I don't think so.

About the only temporary adjustments would be the air/fuel mixture screws. Like Neuner has said, at 14000 feet, you would more than likely require a jet change, reduction in size. If you don't, it will run rich, however, it still may run well enough for you. If you dont change anything, let us know how it runs.

 

[manitou]

Thanks Fastatv. It would only be at 14,000 feet for a short stay on top of Pikes Peak. I guess 'carbureted' cars made it to the top for several years prior to fuel injection. Maybe I'm worrying about this too much.

 

[CJim7]

I had to re-jet mine right out of the box

 

[Neuner]

I had to re-jet mine right out of the box

maybe you can convince him to go propane. Too bad filling up along the way would be a pain?

 

[CJim7]

maybe you can convince him to go propane. Too bad filling up along the way would be a pain?

Lol. I recommend propane to anyone who uses their rig primarily offroad. Mainly because the tanks render the rear passenger compartment useless for passengers
The biggest issue with filling up is obviously there are fewer places to do it!

I just got my hands on 2 larger tanks (I think they are 12 gallon).....Now I can extend my range when I'm not trailering

 

[mtnwhlr]

Maybe I'm worrying about this too much.

A little more timing will help.

 

[jdcaples]

A little more timing will help.

How many degrees positive timing will help?

-Jon

 

[mtnwhlr]

I would start at 5* more.