I just removed my asian carb and installed a brand new Weber 32/36. Truck lopes real bad at idle and as you accelerate. I cant seem to get it to smooth out. 1981 , timing at 5 btdc, new distributor, fuel pump, plugs and wires. Any suggestions? Vacuum leak maybe?

 

Check for vacuum leaks. I use a propane torch...unlit with the gas on.....prod around the carb with it and if it idles up...you have found the leak.

Have you read up on initial settings on the weber?


Are you running an adjustable fuel pressure regulator? Webers like about 3.5 psi.

 

im running stock mechanical fuel pump without a regulator. I turned the adjustment screw that is on the rear passenger side corner of the carb in all the way and then backed it out 1 complete turn. Also, what do you guys do with the real big hose that connects to bottom of the stock breather? Lots of vacuum there so I plugged it. Is that correct to do?

 

You need a regulator. Stock pump is too much for a weber.

It puts out 7 psi or so.

Did you read the manual that came with it? Read any install threads here?

Reg is mandatory....I know this for a fact. I just did a weber and it ran like crap without one.

 

You need a regulator, my desmog thread tells you exactly what you should buy and even has a niffy way of mounting it to the intake manifold

That would be your mixture screw which typically has a baseline adjustment around 2 full turns from bottoming out. Since you don't have a FPR, then you're essentially force feeding the Weber and dialing the mixture screw in further to compensate for the additional pressure. Get a FPR

If you are talking about the bung on the valve cover closest to the oil cap, then you DO NOT want to cap it! You can do one of two things 1)route the hose to the fitting on the filter housing of the Weber or 2) put a breather filter on it. I used a breather filter because if my engine decides to spew oil out the breather for some ungodly reason then at least I'll just get a mess in my engine compartment and it won't get sucked down my carb.

Scope out my desmog thread, it should help you with the hose routing:
https://www.yotatech.com/forums/f114...torial-264405/

 

I looked at your desmog thread and the big hose I'm talking about is the one coming off of the reed valve. What do I do with it, if I'm not removing the reed valve at this moment?

 

For now would this regulator do the trick?
http://www.autozone.com/autozone/acc...er=266096_0_0_

 

yup sure will

 

You remove the reed valve... why would you keep it if you don't have it hooked up?


Yes, but I wouldn't trust anything that doesn't have a gauge attached to it. How would you know that 3.5 on the dial is REALLY putting out 3.5 PSI?? I will tell you from years of experience of working on cars, trucks and motorcycles that cutting corner and trying to save money and time will not save you time and money in the long run. Damn near every single quick fix and "until I get the money" temporary solution has cost me more money than if I just did it right to begin with. You don't need to buy expensive parts, you just need the right parts for the job.

 

FPR $29: (WAAAAY better than that Spectre FPR and only a few bucks more)
http://www.summitracing.com/parts/hly-12-804/overview/

Gauge $30:
http://www.summitracing.com/parts/mrg-1563/overview/

 

I used the cheap gauge...hooked my own test gauge to it...was spot on. Took the test gauge off, set it to 3.5 psi...business.

I got the holley one...the don't just willy nilly put out a product that is that out of spec. Hell maybe it is Mr Gasket. I dunno. Mighty mouse gave it to me.

Gauge is a nice addon. But not needed in my case.

Make sure do do a nice fuel filter inline while you are at it or at least change your old one. No use gunking up out new webers.

 

I used the Weber regulator. Expensive...and no gauge, but if it's from Weber I know it works with my Weber carb.

Of course I have an electric fuel pump so I probably didn't need it anyways...

 

okay guys i'm really getting frustrated!! I installed fuel pressure regulator.
turned this screw out 2 full turns



backed this one out till it wasn't touching. (this is idle adjustment screw??)



started the truck and turned the first one in slowly and the best it runs is all the way in. and it still lopes and stutters as I slowly give it gas. it just wont smooth out anywhere. I used carb cleaner and checked everywhere for vac leaks. found none.
Is this the correct way to tune it or am I an idiot??


what is this long skinny screw for in the back center of the carb?

 

Why dont you have the choke hooked up yet?

 

didn't figure I needed to. truck starts fine. Do you think that's my problem? I have ran several Hollys and Edelbrocks without choke hooked up. Are these carbs that different?

 

If you hook it up to switched 12v, it will be one less thing we can blame it on.

I would do it for sure.

 

Ok I will, now am I doing the tuning procedure correctly?

 

Did you read the weber tuning deal? I dont remember the screw turns exactley...but there is a post somewhere about tuning a weber. Maybe even 4crawler did it. Let me poke around.

 

here you go....

http://www.carburetion.com/Weber/adjust.htm

 

Yes I did, but it's not real clear on what screws are what. Just gives their names, so I'm not sure I'm doing the right thing with the right screws at the right time bla bla bla