weber carb issues

[jeep90]

1068771

just put my weber on yesterday. it actually idles now. the only problem i am having is when i floor the throttle to fast it starts to sputter and backfire in the carb pretty bad. any one know where i can get a picture of a weber installed so that i can look at it and see if i have anything hooked up wrong. i got frustrated with the vacuum hoses and just started hooking stuff up until it ran. one more thing is the egr necessary? i think i just need a picture. thanks in advance. :-? [addsig]

 

[chinard]

1068774

Check your ignition timing.
I was having these issues like crazy, even after i installed my juicebox.
Once i got a timing gun and set the ignition timing, it was smooth as silk.

Also, another pointer is to make sure you don't hit the gas too much when you are starting the engine. If you have any flooding, that will also cause sagging and backfiring.[addsig]

 

[jeep90]

1068776

other than emissions is the egr really necessary? the haynes manual says that if the egr isnt hooked up it will cause severe engine damage.[addsig]

 

[chinard]

1068778

Are you talking about the hoses for PCV intake and return?
Yeah, they have to be hooked up because they regulate pressure in the valve cover.
Without them hooked up the engine performs really badly.

Quadratec has a couple of good installation guides, have you checked them yet?
here's the links:
http://a1197.g.akamai.net/f/1197/5580/6h/www.quadratec.com/pdf/weber/551.pdf
http://a1234.g.akamai.net/f/1234/5580/6h/www.quadratec.com/pdf/weber/trouble.pdf

I'll see if maybe this weekend i can snap off some pix for you to show you how my weber's hooked up. Its not that complicated compared to the stock carb.

edited by: chinard, May 23, 2003 - 12:31 PM[addsig]

 

[MudDawg]

1068785

Combustion byproducts, unburned fuel, water, and various acids are removed from the crankcase by the PCV system...If you don't have one on a street engine, after several thousand miles the sludge created will cause major problems...and the acids and water will attack and damage the internals. Frequent oils changes can slow the process...and if you drive the vehicle daily for extended periods of time say at least an hour without turning the engine off it will take longer yet to sludge up.

The longest living gas engines i have seen were in taxis, insurance salesman's cars and in postal jeeps..they were clean as a whistle inside..the worst belong to those who only crank up to go to the store down the block a few times a week, or are used for short commutes. And this is regardless of the brand of oil used as long as the oil change interval was at 3,000 to 4,000 miles and a working PCV system.

Dawg[addsig]

 

[far_right]

1068811

insurance salesman's cars
Dawg

well... exept for my dads impala...haha.... it is a company car and he changes the oil... bout every 15-17k miles.....hahah.... been through 2 transmissions in 55k miles :-O :-O [addsig]

 

[jay89]

1068888

I was having the same problem with my Weber. When I would floor it or get on a highway it would die down them kick in. I called weber you should have a 800 # for help if you need it . They told me to back out the idle speed screw, and adjust the idle mixture screw with a tachometer. Basically you have to find the sweet spot with the idle mixture screw then you can adjust you idle speed. I take a lot of patience but it will be worth it.
Here is a link to help.

Page title:Weber instal'[addsig]

 

[chinard]

1068927

Man, thats a kickass install document

I just used it as an excuse to put in all these funky red silicone vacuum hoses i've been hording, and man does the engine run nice and smooth after setting up my hoses like that.
Damn good thing too because i found that most of my original hoses had rotted through in parts. :-O

As it turns out, several of the hoses were just lying disconnected (such as the EGR) and i didnt even realize it.

There are a couple of things that i don't understand about the vacuum routing that i hoped someone could explain...

First, can someone shed some light on the CTO?!? I mean i've always seen it there, but i'm unclear as to what its function is and how its supposed to work... I mean there are 5 ports on it, do they each have a different funciton, or are they all the same?

Second, the weber install documentation had a connection from the pcv return to the manifold port of the carb adaptor. This routing has it going to a T-connector that also connects it to a port on the canister down below. What does that port do?

Anyways, I HAVE taken pictures of my freshly re-routed vacuum hoses with my digital camera... and I'd post them, but i can't seem to find my little memory card reader for my 'pooter

[addsig]

 

[chinard]

1068945

Okay, i got my memory adaptor working.
Here's a fresh picture of my hose routing. I still have some more stuff to clean up, but i need some more of those silicone hoses and another tee connector to finish the job.

One of the things about the hose routing that is TRULY annoying has to be the positioning of the hose at the bottom of the filter that connects to the back of the valve cover. :-x I've gotta figure out something better to do with that, cause as it stands, it just kinda flops all over the place.[addsig]

 

[jay89]

1069010

Hey chinard, just buy a seperate breather at Autozone or an autoparts store. It is a little filter that pops right into the rear grommet on the valve cover It will eliminate that hose. Were did you get the red vacuum hoses?

edited by: jay89, May 27, 2003 - 04:54 AM[addsig]

 

[chinard]

1069031

Hey chinard, just buy a seperate breather at Autozone or an autoparts store. It is a little filter that pops right into the rear grommet on the valve cover It will eliminate that hose. Were did you get the red vacuum hoses?edited by: jay89, May 27, 2003 - 04:54 AM

I suppose i could do that, but then i'd have to find something to plug the bottom of the air filter with. Not a big problem, I'll check my spare parts boxes and see if i can find a rubber stopper of some sort.

The vacuum hoses are actually from Vibrant and are available in pretty much any colour. They're silicone hoses, so they don't rot as badly as the rest of the rubber ones.
I picked mine up at "canadian tire" here, but to tell you the truth, most import shops carry them for all the little rice-boys.
They also have sets of "braided" metal sleeving for your hoses that looks impressive as hell, but considering how much oil and grease gets built up under the hood, it would be a really BAD idea. The silicone is really friggin easy to clean.
[addsig]

 

[jay89]

1069219

Hey Chinard, How do you have your vac advance on the distributor running. It looks like you have it to manifold vacuum? And I noticed you have a juicbox. Doen't the juice box call for it to be hooked up to ported vacuum on the carb?[addsig]

 

[Jay82]

1069341

I have an 82 CJ7 that is currently stock except for the Weber 38/38. I am having a problem with it after hard acceleration. After I get on it, it will either bog down or stall when I let off the gas. I have my vacuum system hooked up just like the drawing jay89 provided except I have a Y in the manifold to the distributor that feed the air injection valve. Any ideas what would caus it to stall after hard acceleration? It is fine through the acceleration it just dies if I let off fast.

Thanks![addsig]

 

[Jay82]

1069506

Got it fixed. Called Weber and talked to a gentleman named Jose. Basically what we did was to run the the distributor straight of the vacuum port on the carb, plug the vacuum source coming off the manifold below the carb (not the PCV to cannister lead), and ensure the bowl vent and PCV were connected. I also installed an adjustable fuel pressure regulator. Now it runs really well. Now to plug the air injection ports on the manifold.

Jay
82 CJ7[addsig]

 

[richsia]

1069758

Installing a Weber Carb on my 90 YJ 4.2.
NEED SOME SERIOUS HELP!!!
Noticed that the EGR was never hooked up to Vacuum, so don't know if I should hook it up. However my big question is about the Vacuum Line that goes to the Brake Booster. Currently the Vacuum line is Teed off one to the Vacuum switches on the fire wall close to the Valve Cover.
Which Vacuum line should I attach the Brake Booster to?
Also if my YJ isn't hooked up to the EGR now, should I hook it up?
Thanks!!!
Richsia@yahoo.com[addsig]

 

[Jay82]

1069773

Not much help as my 82 does not have power brakes, but here is the number for Weber tech support "800 871 3405". Ask to speak to Jose or Crowley. They squared me away real quick.[addsig]

 

[jay89]

1069813

My brake booster goes to the manifold vacuum port just below the carb and above the egr![addsig]

 

[chinard]

1069823

Hey Chinard, How do you have your vac advance on the distributor running. It looks like you have it to manifold vacuum? And I noticed you have a juicbox. Doen't the juice box call for it to be hooked up to ported vacuum on the carb?

I just left it hooked up to the manifold vacuum. I don't remember seeing anything in the juicebox instuctions that asked for it to be hooked to ported vacuum :-? When i re-did my hoses with the red silicone stuff i pretty much followed This Diagram
Never really noticed any problems with it, What's the diff?
[addsig]

 

[jay89]

1069829

Manifold vacuum is constant where ported vacuum varies with speed. [addsig]

 

[chinard]

1069910

Okay, coming back to This Diagram which shows the distributor hooked to the manifold vacuum and the CTO hooked to the ported vacuum, should i just switch the two vacuum ports, or will i need to do more splicing with T-connectors?

Oh, BTW... Slightly off topic, but I notice by your .sig that you have a weber with the nutter bypass. I thought the nutter bypass was specific to bypassing the stepper motors on the old carter BBD carbs. Any effect with the weber setup?[addsig]