BBD rebuilding question

[Rance]

I'm mostly finished rebuilding a BBD on a 1980 J10 (jeepers, it sure has a lot more parts than a Holley NH!). The instructions say to adjust the fast idle link "Place fast idle speed screw on appropriate step of cam." What the heck is the "appropriate" step? Looks to be about half a dozen of to to choose from. Thanks!

[1979bettywhite]

hmm, from when I rebuilt mine for my CJ, I remember setting it on the second step of the cam, against the high idle shoulder. But I actually went through the entire process of measuring clearances. I recommend doing the first time after a rebuild, sounds like you are going through that process. My BBD runs great after the rebuild. I also added an electric choke and did away with the manifold choke. The tube actually came off in my hand the first time I even touched it.

I have an old service manual from AMC concerning the Carter BBD in PDF. Good picture references in it. If you want me to e-mail that to you, more than happy to. Just PM me your address.

[Stuka]

When the choke is cold, and you push the throttle down once, it will set the high idle. As I recall (its been like 14 years since I ran a BBD), mine was in the middle area. If thats too fast, you can use the lower step, or high step if it isn't fast enough.

[1979bettywhite]

Agree with Stuka. As we have discussed, one pump should throw it to highest step on the fast idle cam when it is stone cold. It will never go all the way to that step on the cam if it is not 100% cold. After cranking (~1600 rpm), a blip of the throttle should bump it down to the shoulder of the high step (~1200 rpm). From there it will be all about how cold it is outside, and where you have set your choke cover/spring tension, as to how long it remains on the fast idle cam. At some point it will finally kick down once it is warm enough. But if you set it up properly, you can crank it 100% cold, throw it in gear and roll. Should not bog down on you at all as it matches the rpm and burn rate of the fuel for the temps with the choke. I do this all the time with the CJ. Sometimes it takes 10 min + before she finally settles down to a normal 700 rpm idle. But those are the days when I am brave enough to drive her in 40 degree temps with just a bikini top (yikes!)

I have had a decent amount of time with my carter on the CJ. She has been good to me, as much as she does get a bad wrap. But she has also taught me quite a bit about carbs. And some patience thrown in, lol.

[Stuka]

I have had a decent amount of time with my carter on the CJ. She has been good to me, as much as she does get a bad wrap. But she has also taught me quite a bit about carbs. And some patience thrown in, lol.

I got annoyed at mine pretty quick. I put the webber only 14 years ago, and it has never had an issue. No rebuilds or anything.

[Cecil14]

The BBD can be made to work, sure. But there are so many WAY better carb options out there, it just really doesn't make sense for most people to bother. The Weber and MC2100/2150 are better carbs in literally every way.


aa

[1979bettywhite]

Yes, I agree. But I guess I am a glutton for punishment? Just really wanted to get mine to work well and figured it would be a great learning experience.


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[tgreese]

If you bought a rebuild kit, the instructions should have a table of initial settings, depending on the application. These kits are made to cover as many different applications as possible. If missing from the instruction sheet, it should be listed in the TSM at the end of the section or chapter, or possibly in the text that describes re-assembly.