Weber carb problem

[DiscoTodd]

Well I was adjusting the carb after adjusting my valves and found that when I turned the mixture screw all the way in it would idle high, instead of lower idle. I've been having low idle problems off and on after warm up. all vacuum lines are new. Also right before I adjusted the carb I drove it around and sometimes I would have to pull the choke half way out to keep it from stalling at stops. Does not make any sense to me.
Cheers

1976 Siii 2.25 stock

 

[DiscoJen]

Some folks like Webers but I'll have to state that I just can't see the love for them. I also had a problem with the damn thing running lean all the time. No matter what I did I couldn't get a good mixture. The previous owner also had the same problem.

Another problem with the Weber is that they do not tolerate dirty fuel. The jet gets clogged really easy because of it low location in the bowl. You can try taking it apart and giving it a good cleaning and that may help.

I ended up switching to a Rochester and am happy with that. The old Weber can sit in the basement til hell freezes over for all I care.

 

[singingcamel]

The way I understand is that when you screw in the mixture screw ,your leaning the air fuel mixture , running lean, (causing you to run with the choke out) back it out 1 1/2 -2 turns and adjust the idle screw.
You may have a gasket leak at the base of your carb or a warp or warn phenolic block , the black thing the carb sits on , torque the carb down hope this helps..
I'm a big lover of the weber, rochesters are fine as well as there jetted correctly , if not they can really carbon up the valves. Sorry DiscoJen , I still like you.

 

[DiscoTodd]

I had to pull the choke to get it to not stall out before I started messing with the carb. which does not make sense cause pulling the choke richens the mixture, but then when I was adjusting the carb, it idled better when I had the mixture screw completly turned in which was running lean.

 

[singingcamel]

You may have a carb base leak, tighten or change out the gaskets.

 

[LRNationals]

ditch it for a rochester carb. webbers are way to finiky. you will get more flow from the rochester, and a bit more umph. always hated webbers more for british race cars!

 

[LRNationals]

http://www.expeditionlandrover.info/landRoverFAQ/FAQ_rochester.htm

 

[LRNationals]

an other link http://www.discoweb.org/41704archive/DiscusArchive/messages/3/28509.html

 

[DiscoJen]

Another thing with the Weber, do you have a phenolic block that gets the base of the Weber up off the manifold? You also might even be able to see a leak at the base, check for varnish built up around the lower seam/base of the carb.

I always had to let mine idle with the choke all the way out for 10 minutes, even in warmer weather, just to not sputter to a halt before the end of the block.

Not trying to turn you against the Weber if you are dead set to keep it. But man the Rochester is great if jetted to your altitude. Better at off-camber situations if you offroad, too.

Rochester and electric fuel pump were the 2 best things I've done to truck. Think I paid $35 for my Rochester...and it came with a rebuild kit, and it also had the correct jet for my location.

 

[DiscoTodd]

Jen where did you get your roch?

 

[pdxrovermech]

what no love for zenith carbs?

 

[DiscoJen]

I got mine off a guy in California (Goat Man) through Guns n Rovers. Lots of folks with parts there, it'd be a good place to check.

Note: If you change, you'll have to tinker with your linkage as it works just the opposite of the Weber.

Try cleaning your Weber really good first and snugging it up and see if that helps. It might get you by before making the switch.

I've never tried the Zenith actually. I bought a new aftermarket one from AB but the I went with the Rochester cause it looked so simple and rebuild kits available locally at Napa.

 

[DiscoTodd]

Thanks for the tips , I'm going to be on the search for a Roch B, do you know what number your's is Jen? Mean while I ordered a $29 weber rebuild kit and the black spacer thingy w/ gaskets, and rip this weber apart and do like you said and give it a good cleaning. Galen had this weber put on my series brand new about 3 years ago.

It's so mind boggling how I can turn the mixture screw all the way in and it idles perfect, and before I even touched the carb , i'd have to sometime pull the choke half way to get it to idle......

 

[DiscoTodd]

Well AB sells Zienth copies, I never really thought about them too much, what does everyone else think? BTW I do not have any of the original throttle linkage.

what no love for zenith carbs?

 

[DiscoJen]

With Webers being so sensitive, after 3 years it's high possible that simply a good cleaning and rebuild will do the trick. Use a good cleaner to help dissolve any crud.

Do you have an inline fuel filter before the carb? Webers prefer really, really clean fuel. Make sure you put in a fresh inline filter when you put your newly rebuilt and clean carb back on. Especially if you've got any crap or rust in your fuel tank.

I can't remember which # Rochester I got. It's actually two different ones put together as the original # tag is still on it. It's pouring down rain now or I'd go check.

 

[DiscoTodd]

I do, I have one right before the elec. fuel pump and a filter right before the carb, with a return line on the filter. I did have some crap at the bottom of my bowl when I took the carb apart. The black spacer thingy and the gaskets looked old and had some old rtv on them. I have a gut feeling too that it just needs a cleaning and new gaskets.

 

[singingcamel]

I'll look at the shop today . I think I have a few around .

 

[DiscoTodd]

Great thanks!

 

[DiscoTodd]

Ok well I rebuilt the carb, with gloves and no beer was involved. Turned out great. New spacer thingy and gaskets, even used copper high temp RTV.......went to tune the carb(warm) and it's still weird a little bit, At least this time when I turn the mixture screw in it idled rough but no die. my only concern is the idle screw is not even turned in a 1/8 of the way past touching. I have the mixture screw turned out more rich, due reading webers run lean.

also the old mixture screw was very shapr , needle like on the end, the new one is pretty blunt and thicker.... Better?

cheers I was just happy to drive to work today

 

[J. Toronado]

hows it running now? that weber is almost brand new. a year maybe.