Weber Help

[82Laredo]

I installed a new 32/36 DGEV with a holley regulator a couple months ago on a 82 CJ7 258 I had just purchased. It ran like poo with the stock carter which led me to the weber conversion. After installing it was running and idling great without any adjustment but it seemed down on power, would only go 65 mph down hill. First things to check are timing (already installed new plugs/wires/cap/rotor) and making sure its going WOT. The timing is spot on now but discovered I wasn't getting wide open throttle. I adjusted the linkage to compensate and that's where the trouble began.

Symptom: When I get into the last 20% of the pedal it starts bogging/hesitating and occasionally pops back through the carb. It does this whether under load regardless of gear or RPM, or free revving.

I reduced the fuel pressure from 4.5 to 3.5 and this made no difference.

Decided to check the float level even though its brand new and my measurements don't really make sense compared to what I've found on the web. It has the plastic floats and the measurement I've seen on the internet shows 35mm with the top held vertically and 51mm with the float hanging (top perpendicular).

With a digital caliper I measured 37mm and 44mm. The plastic float itself measures 26.5mm. How do I adjust to get those settings, seems like no matter what I'm always going to have a 7mm swing in between. Maybe I'm looking at it wrong.

Any thoughts on this or my carb problem???

Thanks for the help guys, I have already been through so much getting this rust free CJ road worthy I'm about burnt out, and I bought it for my wife

 

[82Laredo]

This is what I'm basing the float adjustment off of:

Redirect Notice

And the jets are 160/160 btw

 

[numbersix]

Sounds like your float level is correct. You mentioned the jeep "idled great without any adjustment", have you since made any changes to the idle / mixture screws? The popping carb may be trying to tell you your mixture isn't correct.

 

[82Laredo]

I have not made any adjustments to it, tonight I'll go by the idle mixture adjustment procedure and idle speed setting per the redline website. I guess this is the place to start before buying a jet kit.

I'm assuming the critical float measurement is the 35mm, this is the one that shuts off the fuel so I should be good to go.

thanks for the reply!

 

[numbersix]

I've never encountered any carbs that are "plug and play", most ship from the factory close enough to get the engine started, but always require some adjustment. You'll want to keep using your FPR and keep it at 3.5 psi. Let us know how it goes.

 

[jdcaples]

My Jeep's PO installed a Weber.

It ran fine until I developed a vacuum leak, which resulted in pops so violent, the throttle valves would lock closed, starve the engine of air and require some impact encouragement to free up.

Bottom line: verify you don't have any vacuum leaks.

-Jon

 

[jdulmer]

If it bogs down when opened up, you're running rich.



"Libertatem Aut Mortem"

 

[Fastatv]

I have not made any adjustments to it, tonight I'll go by the idle mixture adjustment procedure and idle speed setting per the redline website. I guess this is the place to start before buying a jet kit.

I'm assuming the critical float measurement is the 35mm, this is the one that shuts off the fuel so I should be good to go.

thanks for the reply!

The other adjustment is the drop, which may not be as critical, however, it is important that it should be as close to the factory recommended setting as possible. From what your describing, sounds like your running out of fuel...popping is an indication of "lean". Also, the bogging ( as I describe bogging ) is again...too much air, not enough fuel......lean. Question for you: is the carb a vacuum operated secondary or is it mechanically operated. Two barrel...right?

 

[jdulmer]

Follow the instructions, set base line, and tune. As long as you have the right jets, you should be fine. It is usually that simple. I just rebuilt mine last month.



"Libertatem Aut Mortem"

 

[jdulmer]

Is it popping as the throttle is closing (coast down), or while it's in the 80-100% open range? Maybe I am misunderstanding...



"Libertatem Aut Mortem"

 

[82Laredo]

Is it popping as the throttle is closing (coast down), or while it's in the 80-100% open range? Maybe I am misunderstanding...



"Libertatem Aut Mortem"

It stars bogging at about the 80% range and will pop if I continue to hold it open. No popping on decel and returns to and idle fine. I didn't get a chance to work on it last night but will report back.

 

[82Laredo]

It's a mechanical secondary and the linkage/accel pump appears to be operating properly.

 

[Neuner]

What is your timing set at?

 

[82Laredo]

What is your timing set at?

5 degrees at idle with the vacuum advance hose unhooked and plugged as per the sticker in front if the radiator.

Thanks again for the replies guys

 

[jdulmer]

Hmm... Mine's never done that. If rich, mine pops on deceleration. A good indicator is the color of the end of your tailpipe :
White = lean
Black = rich

Just trying to help.




"Libertatem Aut Mortem"

 

[82Laredo]

Made a little progress. Turned fuel pressure down to 3psi per redlines recommendation and set the idle mixture at 1 1/2 turn out indicating the idle jet is a tad rich, plus it idles at 650 with the idle speed screw only 1/8 turn in.

This helped slightly reduce the bogging and if I roll into it slowly at higher rpm it will take the fuel without popping back, but still has some hesitation.

I'm going to try 2 1/2 psi FP before I start throwing jets at it haha

Thanks again for all the help. A little progress goes a long way. I'll keep updating this thread with whatever changes I make to help anyone that runs into the same issues after a weber swap.

 

[numbersix]

5 deg of advance seems a tad low, you aren't running factory carb / emissions equipment anymore. My sweet spot was 8 deg BTDC and ran best using ported vacuum. Mine was stock minus all the computer junk, pulse air, etc..also an HEI distributor with the 32/36. Are you using manifold or ported?

 

[Dan77CJ7]

Is the fuel return working?

 

[82Laredo]

5 deg of advance seems a tad low, you aren't running factory carb / emissions equipment anymore. My sweet spot was 8 deg BTDC and ran best using ported vacuum. Mine was stock minus all the computer junk, pulse air, etc..also an HEI distributor with the 32/36. Are you using manifold or ported?

I'm running the vacuum advance off the small port facing the valve cover, which has vacuum at idle. I'll try bumping the timing to see if that helps. Where is the port on this thing that doesn't have vacuum at idle?

 

[mtnwhlr]

5 deg of advance seems a tad low, you aren't running factory carb / emissions equipment anymore. My sweet spot was 8 deg BTDC and ran best using ported vacuum. Mine was stock minus all the computer junk, pulse air, etc..also an HEI distributor with the 32/36. Are you using manifold or ported?

I would agree that your timing seems low I have found you what to run as much as the engine can take. If it doesn't ping your good.