Idle Mixture Adjustment Wednesday, 09-Aug-2000 18:50:43 writes: I am adjusting the idle mixture on my 40's and I cant get two cylinders(1&2) to respond. I removed the carb, checked to see if the idle jets were plugged, nope. I removed the idle mixture screw and out came the seat, must have been over tighened. I reinserted the seat but I think it might have been damaged from the over tightening. What is the easyist way to remove it and replace it? Its replaceable correct? I removed the pug wires while it was runnin and #4 seamed like it was supporting the motor, it would almost die with out it. #3 close to the same. #1&2 would barly respond, and i lossened the mixture screws way out on them. Why? Im reading the Weber Tech Maunal by Bob, but i havnt found a solution. woo, outa breath now! thank you Billy Moss "HotStreetVw"


HEY BILLY, are those carbs SYNCRONIZED??? if one is open more than the other, EVEN BY A TINY AMOUNT, you can turn screws and dissasemble carbs all day... make sure they are drawing exactly the same amount at idle and then try mix. screws. [no vac. leaks , right??] good luck dennis valley vw (n/t) (09-Aug-2000 19:33:55)

There syncronized, I used my new sycrometer I got from [email protected] Havent found any vac leaks. Thanks Dennis, any other thoughts? (n/t) (Billy Moss "HotStreetVw") (09-Aug-2000 19:39:58)

Billy, I normally find this is because your idle screw on one carb is turned out more than the other (more).. (Greg Ward) (09-Aug-2000 19:56:17)

you could try a compression check to make sure everything is equal. is valve adj. ok?? dennis. (n/t) (09-Aug-2000 19:51:04)

Dennis, did the compression check, 180lbs on each cylinder. I havnt messed with the valves because its a hydro cam, do i adjust them like the solid cams? Thanks. Greg, i tried that, got the same results, humm, how do i fix the idle mixture seat? Thanks dude (n/t) (Billy Moss "HotStreetVw") (09-Aug-2000 20:51:30)

More things to check: are the idle air bleeds clear? is the float on that side sticking closed? Adjust/sync idle speed/mixture with the linkage disconnected from one carburetor, then adjust the loose linkage arm to precise fit. Check compression, plugs, plug wires and connectors, and valve clearances (if a valve is to tight you won't make compression and it won't run on that cylinder). (n/t) (george brown) (10-Aug-2000 04:41:03)

I just went through that with my 42 Webers... (Craig Merrow) (11-Aug-2000 14:33:50)


Billy, I normally find this is because your idle screw on one carb is turned out more than the other (more).. Wednesday, 09-Aug-2000 22:56:17 writes: You need to undo the linkages to both carbs. Back off the idle screws so they don't touch the stops at all. Now screw one slowly till it just hits the stop.Then turn it one full turn to begin with. Now repeat this with the other side. Kick the engine over and try the plug lead trick, it should make a difference on all four leads. All of the above should be done at operating temp. If you sync everything up when its cold, it will change completely when its hot. See how you go Greg Ward


I just went through that with my 42 Webers... Friday, 11-Aug-2000 17:33:50 writes: I had the right carb not respond AT ALL to idle mixture screws...I tried all kinds of stuff, then decided to see if it was the carb or not. I swapped them from left to right, and the problem moved with the carb. Something inside plugged or something; Steve Hollingsworth is going to work on them and see what he can do. Craig Merrow

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