Sotck 71 240z carb problem

[Casey_z]

All you need to to do is develope the fine motor control skills in your right foot;)

Casey

[woytovich]

All you need to to do is develope the fine motor control skills in your right foot;)

Casey

Funny... (not)

The fact of the matter is there is really no way to make this work short of wedging my foot against the tranny tunnel and levering it to push the gas pedal in an uber-controlled way... not practical and not entirely effective in any case..

Thinking of Webers at this point... (and i don't really want to go that route...)

[Gary in NJ]

I don't think Casey is trying to be funny. The 240Z requires a deft touch on the throttle. It is unique and has been a source of complaints from many an owner.

Back to the problem...These are 40 year old cars and it is entirely possible that a prior owner screwed something up. Give something a try...

Disconnect the return spring on the the throttle lever and see if that has a significant effect on the break-out force. It's possible that you have an incorrect return spring.

If that doesn't help, it would be worth the effort to disassemble the ENTIRE throttle linkage & interlock link on the carbs to determine if something is corroded or otherwise binding.

Check the spring first 'cause its easy.

Edited November 29, 2010 by Gary in NJ

[woytovich]

I don't think Casey is trying to be funny. The 240Z requires a deft touch on the throttle. It is unique and has been a source of complaints from many an owner.

Back to the problem...These are 40 year old cars and it is entirely possible that a prior owner screwed something up. Give something a try...

Disconnect the return spring on the the throttle lever and see if that has a significant effect on the break-out force. It's possible that you have an incorrect return spring.

If that doesn't help, it would be worth the effort to disassemble the ENTIRE throttle linkage & interlock link on the carbs to determine if something is corroded or otherwise binding.

Check the spring first 'cause its easy.

I know he wasn't trying to be funny, I appreciate all input on this topic...

I did disconnect the springs and clean/lube them... I thought MAYBE they were all gummed up and sticking to themselves. That did not help. They LOOK correct. They do not seem to require a great deal of force to start to expand... and they do not seem to have any sort of "curve" to their spring rate that would make them tougher at the start... BUT I am willing to revisit the spring thing... and I'll post pics of them too...

Mark

[woytovich]

Where would one get a correct return spring?

[Bruce Palmer]

We have the carb return springs made.

[woytovich]

We have the carb return springs made.

Cool... I'll buy two...

BUT: do you have any additional input on all of this? What do YOU think is wrong, if anything?

Mark

[Bruce Palmer]

ZTherapy disclaimer -- You need carbs!!

Now that that is out of the way, there's not much I can add to what you already have in hand. I've stumbled across this herky jerky gas pedal thing off and on over the years and if memory serves, changing the pedal height helped more than anything plus just getting used to what was going on.

How heavy is the spring that goes to the bellcrank on the firewall?

Maybe shoot us a picture showing the piece the spring and the dogbone hooks too. If the orientation of that's not up and down, but over center that can cause what you're describing.

Call me with a credit card and we'll get the springs heading your way...

[woytovich]

Pictures... Good? Bad?

[bartsscooterservice]

I'm experiencing exact the same problem right now, so I'm bouncing this topic up, did you find any solution ?

[woytovich]

I'm experiencing exact the same problem right now, so I'm bouncing this topic up, did you find any solution ?

I got it 90% better by adjusting the linkages. I had to turn one in and the other out. It was that the way it was set up caused a "bump" in the movement. That bump manifested itself as increased pedal pressure going into the "bump" and then less after... this made the "after" movement too fast. After adjustment the bump i mostly gone.. I plan to adjust more to get it even better.

[bartsscooterservice]

can you tell me what you adjusted ? I did the bellcrank mod, but maybe I shouldn't have done that.