Throttle shaft vacuum leak on new Proform carb!

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KnuckleDuster

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Carb is 750 Street Series mechanical secondary, pn 67213.
It's less than two years old, but it was sitting drained for 5 months while I had the car apart. Now it whistles at the throttle shaft, and is affecting idle settings.
I think I just need the Teflon ribbons, but unsure which size or thickness to order.
Same problem on a Holley vacuum secondary carb I also own. I would like to order what I need to fix both carbs.
Can someone tell me for sure exactly what parts I need?
Any good tips on the repair process are appreciated as well.

Thanks!
 
The vacuum side needs to rotate very easy and I have experienced that the nylon inserts have to much drag, if they are tight they open to slow, and to work they have to be loose and leak air. so your best bet is to deal with it if it is new or get a new base plate if it is worn bad.
 
Is it common for them to wear this quickly?
Shouldn't need a baseplate after MAYBE 1000mi !
Had no issues before storing the carb.
Here is my throttle/kickdown setup.

20180805_084407.jpg
 
try soaking the base in gas to see if they swell I little and seal up . I done this on a mono jet carb one time and it worked just a stupid idea and it worked lol .
 
You need to move your return spring it's in a bad place, everything is pulling back on the shaft so the shaft will wear faster than if the spring is hooked on the end of the throttle cable, that way the shaft just floats and only has a rearward force at full throttle.
 
Obviously from the pics, I have a Lokar kd cable. When I put the car back together after head porting, I had switched to a shorter kd lever on the transmission.
Apparently I set it up too tight due to some bad info I read somewhere about having it set where the lever was partially engaged. The more I thought about the factory rod setup, the less sense that info made.
I went back to the longer lever and got the kd setup where there is no tension at idle. The Proform is doing better now. Hopefully I didn't do too much damage in a few drives. Live and learn. I will also look for a better throttle return spring setup.

I would still like to fix my Holley, though...
 
Seems someone used to make a kit that came with a reamer and bushing to use bronze bushings on the throttle shafts.

If you don't want to do it, contact Dom at Thumpr carbs, Mark Whitner or even BLP as they may do it. IDK if BLP will work on Proform stuff.

Also, I agree with moving the return springs and those springs look like they'd shut a barn door. I don't like all that spring. There is return springs on the throttle shafts, plus the return springs.

The secondary return spring should be just enough to shut the throttle should the main spring fail, and the springs on the throttle shafts fail.

Some lawyer had to dream up the idea of double redundancy on return springs.
 
It's not the Lokar springs. They are actually quite soft. As I'm sure you are aware, there are dozens of us on this board, plus thousands of others using the Lokar setup on all sorts of cars. If the springs were the problem my 750 Holley would be worn out by now and so would 100s of other carbs.
 
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