stickey throttle plate when car is on

[Anonymous]

i have a problem with the throttle plate feeling stuck when its completely shut...i thik its too much vacuum holding it or something..when its open its fine...when the car is off i can operate it just fine so its not stickey..i also cleaned it with carb cleaner just in case..i thought it could be the gasket, but the hole in the gasket is bigger than the hole in the carb...would it be allright to drill a small hole in the throttle plate?

 

[Anonymous]

Well...i think i'm gonn a drill a small hole in it to see if it works better...my carter RBS has a hole in its throttle plate so i guess it should be all right.

 

[Anonymous]

If you drill a new hole, then you'll have troubles with idle mix adjust.

If carbs have high mileage, they often wear a groove in the venturi throat where they close. Typically, you can only see this groove from the bottom side of the carb, because it may be only .010" deep or so.

With the carb off the car, open the throttle plate all the way and gently sand off just the edge of the groove with emery paper (wrapped around your finger). Clean thouroghly with carb cleaner to remove the metal powder and try it again. This usually fixes it for another 10,000 miles.

 

[Anonymous]

i saw that groove when i had the carb off actually...thank u very much for telling me about it though..it looked higher than the plate but i will be sure to sand it down...thanks again, i appreciate it....(and yea...drilling the hole didnt do anything so i will be replacing the plate with one off my parts carb..no big deal)

 

[simon]

just to throw in some more useless information and baiting: There are some places that can fix a carb´s worn, grooved throttle body.
if the groove isn´t too deep, the overall radius is enlarged on a CNC machine and a slightly larger throttle plate installed.
Because enlarging the overall size of the throttle diameter may weaken the venturi effect, there´s another fix for rather deep grooves.
if the carb body has enough "meat" all around the throttle plate area, the throttle body is completely hogged out, then a new sleeve is pressed in.

Given the fairly good price of a completely restored and rebuilt carb from pony carbs, not to mention the small money you have to pay for 1100s on evilBay, sleeving a throttle body will probably be overkill...

 

[Anonymous]

Take care to make sure that the plate is aligned correctly when replacing or installing the throttle plate. The plate can shift slightly when re-installed and create the sticking problem you mention. Also worn throttle shaft or shaft bushings may cock the plate in the bore .
Doug

 

[Anonymous]

thanks guys for the help...i sanded the inside...the carb is a three piece body and the lower section is sorta off and not smooth, so i took the dremel and sanded it fairly smooth and then polished it...it pretty much got rid of the stickyness and what is left really isnt too bothersome...there is just a dead spot right now..accelerator pump is good but i think it needs adjusting. thanks again