Weber 32/36 DGAV Throttle Linkage. Stumped!

[kiloscott]

Way ahead of you.

 

This truly has me stumped. I'm leaning towards increasing the tension of the throttle return spring. But, given that it's an early 70s CA 2002, I'm pretty sure my thinking is correct. Does your 74 have a stop on the underside of the gas pedal? What would be the point of this other than to prevent operation at full throttle?

 

As everybody knows, CA's smog problems in the 60s were caused by 4 cyl 2L German motors, not by the gas guzzling porkers being cranked out by the automotive geniuses in Detroit.

Edited April 29, 2021 by kiloscott
Clarity

['76mintgrün'02]

I am sure the carburetor was meant to operate at full throttle.  It's not an emissions setting.

 

If they put a stop on the pedal, it's because they had all the travel they  needed to achieve full throttle.

 

Have you unscrewed the rod that you extended the threads on?  It needs to be close to the factory setting (length).

 

There is an idle-up cam associated with the choke mechanism.  Are you certain that it is in the "off" position and the little screw is not hitting one of the steps?  That little screw might need to be loosened, if it is resting on that instead of the idle speed screw at the linkage end.

 

Sharing photos makes it easier to help you.

Tom

 

Speaking of photos, here's a thread that shows some pedals.  Hopefully there is helpful information for you in there somewhere.

 

 

Edited April 29, 2021 by '76mintgrün'02

[2002iii]

My 1974 2002 doesn't have a stop under the gas pedal, they were for automatics and tii's. My car also had a weber 32/36 for a couple decades and it definitely went to full throttle.

 

I'm guessing that your car was probably originally an automatic that has been converted to manual. Like a lot of 02's yours was probably not well taken care of and not adjusted properly. Most people don't know how to work on older cars and/or carburetors anymore. Also if the motor mounts are shot and/or your engine is running rough it will effect the throttle linkage.

[Lorin]

10 hours ago, kiloscott said:

Thank you to everybody for their considered replies.

 

Got under there and looked at the bottom end of the rod connecting the gas pedal to the linkage that operates the carb. The function of this rod is strictly linear. What I did by cutting more threads at the top end of the rod was compromise whatever adjusting capacity there might be at the bottom of the rod. I eventually arrived at full throttle, but in doing so I can no longer adjust the idle speed to 1000 RPM or lower.

 

If anybody is in the sort of adventurous mood I was in when this whole thing started, they might like to do the following:

 

1 Take off the air cleaner and expose the throttle linkage and the throat of the carburetor

2 Press the gas pedal full to the floor and keep it there with a brick or piece of wood or something. You don't even have to start the motor.

3 See if you can't further open the throttle at either the carb itself or by pressing down on the pedal rod. I was able to do this by quite a lot and was quite surprised.

 

This led me to cut more threads, I then road tested things and Hey! What's this?

 

Factor in the stop on the underside of the gas pedal and it makes me wonder how a 32/36 is actually meant to operate. It seems designed to not let you run at full throttle, which would have been foremost in the minds of 1970s CA smog regulators.

 

I can see how installing a throttle return spring with much greater tension might solve this problem, as I can get the car to stall by twisting the linkage strenuously in the opposite direction and fully closing the butterflies. But the necessary tension seems like it might make the gas pedal rather difficult to operate.

 

Will get this sorted and report back.

 

Just one more effing thing...

 

Thanks!

 

Scott

 

You really need to do exactly what I suggested. 
 

 Your pedal can’t open the carb all the way because The Pedal is not retracting far enough. This has nothing to do with return springs and linear linkage. 
 

I’m a little surprised you would ask for help and not try the solution provided and decide it doesn’t work !  
 

Your pedal needs to retract further so it can move further during its stroke before it stops on whatever it’s hitting such as carpet. Changing the angle of the lever off the pedal box is the ONLY thing that affects this.  When you reposition the lever you are changing the position of the arm that glides on the pedal which changes the amount of pedal travel inside the car. You can adjust this lever so you have TOO MUCH travel and risk damaging the the linkage and or carb. 
 

My method lands you very, very close to achieving full throttle with the gas pedal matted. 

 

 It is also possible to have too much crap under the pedal but I would address possibility that after not being able to achieve WOT with the current situation and lever adjustment. 

 

 

 

 

 

 

 

..

Edited April 29, 2021 by Lorin

[kiloscott]

Took me a few minutes staring at the accelerator pedal shaft and lower throttle arm before the lightbulb went off. This is nothing remotely like my old VW bus. There was indeed slippage in that connection and the jaws of the lower throttle arm did need tweaking with my Dremel. It's all back together and I now have both full throttle and proper RPM at idle. Will take it for a spin this evening.

 

I didn't install this 32/36 and didn't set it up, but I can easily imagine somebody hacking things at some point to pass CA smog back when this had to do so. Or it may have just been age and wear. Will never know.

 

Many thanks for all your help!