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Carb adjustment and idle rpm

6K views 5 replies 6 participants last post by  L82 
#1 ·
Just wondering what everyone sets there idle at on 96 formula 3 600 triples? Also what is everyone's secrets to adjusting and tweeking their carbs
 
#2 ·
Most shoot for 1800-2000 rpm. Triples seem to foul plugs at idle more than twins. Many of us have had success changing pilot jets to 45's. Far less fouling and throttle response is a bit crisper in the lower ranges.

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#3 ·
I have my girlfriend's F 111 idling right around 2000 rpm. Anything less, and she doesn't want to start when cold. As far as " tweaking", there's different procedures for each function of the carburetor, so it depends on what you want to tinker with...To adjust the slides to WOT, wide open throttle, use the cable adjustment on the top of the carburetor. This is the ONLY function of the adjustment. hold the throttle wide open, and feel inside the top of the carb throat. All three bottoms of the slides should be flush with, or just a nary hair below the carb throat. Now to adjust the synchronization, it involves a mirror, a 3/16 drill bit, and patience. Find a mirror, like an old rear view out of a car. Place it to where you can see all three carb slides at the same time. Back off the slide adjustment screws,until they are no longer touching the slides. Open the throttle, and insert the smooth end of the drill bit into the carb,and under the slide. Screw the slide adjustment screw in, until the drill bit moves a little....Very little..Stop. open throttle, remove drill bit, repeat on other two carbs. Now looking into the mirror squeeze the throttle slowly, and observe the slides. All three MUST lift perfectly in synch. If they don't, use the slide adjustment screws to synchronize them. This is how to synch your carbs... NOT with the slide cables. Once you think you have them absolutely perfect, start it up. Use the slide adjustment screws to raise/lower the idle... Careful to keep the slides in synch at the same time.. I hope this helps. I'm sure there are other posts on this subject also. Use the search on this forum, and see what comes up..THINK SNOW!!!
 
#5 ·
I have my girlfriend's F 111 idling right around 2000 rpm. Anything less, and she doesn't want to start when cold. As far as " tweaking", there's different procedures for each function of the carburetor, so it depends on what you want to tinker with...To adjust the slides to WOT, wide open throttle, use the cable adjustment on the top of the carburetor. This is the ONLY function of the adjustment. hold the throttle wide open, and feel inside the top of the carb throat. All three bottoms of the slides should be flush with, or just a nary hair below the carb throat. Now to adjust the synchronization, it involves a mirror, a 3/16 drill bit, and patience. Find a mirror, like an old rear view out of a car. Place it to where you can see all three carb slides at the same time. Back off the slide adjustment screws,until they are no longer touching the slides. Open the throttle, and insert the smooth end of the drill bit into the carb,and under the slide. Screw the slide adjustment screw in, until the drill bit moves a little....Very little..Stop. open throttle, remove drill bit, repeat on other two carbs. Now looking into the mirror squeeze the throttle slowly, and observe the slides. All three MUST lift perfectly in synch. If they don't, use the slide adjustment screws to synchronize them. This is how to synch your carbs... NOT with the slide cables. Once you think you have them absolutely perfect, start it up. Use the slide adjustment screws to raise/lower the idle... Careful to keep the slides in synch at the same time.. I hope this helps. I'm sure there are other posts on this subject also. Use the search on this forum, and see what comes up..THINK SNOW!!!
great post... something to add, when adjusting your idle turn the screws 1/4 turn at a time,(to keep them in sync)
 
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