Edelbrock throttle shaft's

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pjc360

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I have a 600cfm manual choke edelbrock performer carburetor that is not even a year old yet and doesnt even have over 5000 miles on it and i just noticed something that really pisses me off.
The throttle shaft on the drivers side is leaking fuel, i sprayed carb cleaner there while it was idling and the idle smoothed out considerably... So also a VACCUM LEAK. I'm sure many of you know that i hyave had a hell of a time tuning my engine and i think it's pretty safe to say that this is why.
I have changed intake manifold gaskets looking for the vaccum leak, wich i did have a vaccum leak at the intake, so it wasnt a total waist of time.
But man i have been pulling my hair out trying to figure out what in the hell is wrong with my engine and i am pretty darn sure this vaccum leak at the throttle shaft is the culprit, because its a fairly good sized vaccum leak, the idle drops quite a bit when i hit the shaft with carb cleaner.
So today i purchased a brand new 1806 edelbrock 650cfm vaccum secondary electric choke thunder series carburetor. I figured i would stick with an edelbrock since i have 3 or 4 different strip kits with jets, rods, springs, different accelerator pump squiters and accelerator pumps and i also have multiple books on the edelbrock carbs and i am most familiar with them.
I just wanted to ask if there is anything i can do besides running a softer throttle return spring to keep the throttle shafts on my thunder series carb in good leak free shape? I don't know if my return spring is to blame for the shafts wearing out so fast on my performer, or if i got a lemon from edelbrock? Or if i was too hard on it? I just dont know, I couldnt believe it when i saw it because this performer is barley a year old with hardly any miles on it. Also is there anything a guy can do to fix this issue? I opted for the 650 thunder series because i wanted an electric choke and vaccum secondarys anyways and i planned on getting a thunder series to replace the performer series anyways, it's just it happened alot quicker since i discovered this issue with the performer series.
 
Much has to do with the mechanical linkage, of translating linear motion to rotary motion. Modern vehicles often use a pulley at the TB shaft to wrap the throttle cable. This enables smooth rotation with less shaft load. Not sure it a conversion is possible. You might have to adjust what you have for best alignment, for pull back without side loads off idle.
 
Most times its tne throttle cable adjusted to tight. Have someone hold the accelerator to the floor. hold the carb all the way open and just take the slack out of the cable. Making the cable to tight puts pressure on the shaft when flat out and pulls the shaft rearward to hard causing wear. Just one thing I thought I would mention.
 
eddy carbs don't have vacume secondaries ,they have an air door.
 
Personally I would get on the horn and call their tech department at Edelbrock to see if they offer a rebuild or exchange program for Carbs. When lining up the butterflies with the port opening in the carb base can be a pain in the ***. The shafts on my Holley 600 cfm vacuum secondaries had the same issue. I took it all apart and replaced the shaft seals/bearings with holley teflon pieces. That was a bear to say the least and I was 16 and hadn't a clue. It helped to smooth out the idle and felt better through the range of motion of the pedal. Let us know what happens.
 
Well i just bought a new carburetor, This time i went with the 650 thunder series.
I guess when i put my new thunder series on i will make sure the throttle cable isnt too tight and try to line everything up best i can.
I did run a 1 inch 4 hole spacer under my performer, and it did make my gas pedal stiffer, so maybe that contributed to the wear of the shaft.
In all of my edelbrock carburetor books it says it's not adviseable to try and fix a worn throttle shaft and to pretty much consider a new carb.
I cant believe i didnt find this sooner.... I knew something wasnt quite right with the tune of my engine, altho it does run very well right now, i cant wait to see how it runs with this new thunder series carb that doesnt have a fat vaccum leak at the throttle shaft.
 
I also have another question about the differences in the 600cfm performer and the 650cfm thunder series. I have read that there are some differences in the air bleed sizes and the idle feed restriction sizes. I was thinking the only difference was the tuneable secondary's.
But i have read that the 650cfm thunder series is a little bit richer in the idle circuit compared to the 600cfm performer. Is this true? Or are they the exact same?
 
ill bet you took a 2 bdl off and put a 4 bdl on. right? on the chrysler 2 bdl, the linkage mounts at the carb conection closer the center, and closer to the rear, than a 4 bdl. the 4 bdl cable is longer to reach the 4 bdl, and the bracket is more out board, than a 2 bdl. if you dont use the 4 bdl parts the carb may lock open. just check the factory parts book.
 
I also found out through the school of hard knocks that using a real strong return spring also will contribute to premature shaft play.
 
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