carb

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rustyrescue
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carb

Post by rustyrescue »

I have had little time to look into our FB series 2 due to the rubbish weather but am working on the plan! the carb as mentioned is clearly wrong....it starts and sounds good but idle is all over the place as high as 3 or 4K! then down to 1200 ish and back.
The choke does not self return and it seems a stupid idea.....can the vacuum bits etc be plugged and simply have it manual?
I have not decided if it operates only a choke flap and fast idle or enriches fuel.
I can see at the rear where a vacuum capsule is it is pressing on the throttle link....if I push it gently I can work it down a bit dropping the revs.
Any guidance on this carb much appreciated....I have a 79 mazda workshop book and a haynes one too.
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gt_james
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Re: carb

Post by gt_james »

the choke can be used manually yes, and some of the rat's nest can be removed. Are you talking about the dash pot on the throttle linkage holding it open instead of dampening it?
rustyrescue
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Re: carb

Post by rustyrescue »

yes I think it is that.....not had a proper look, but there is a module that seems to operate on the linkage and could be a damper. What can be pulled on the auto choke nonsense? I come from a day auto chokes were so unreliable kits were sold to convert to cable only. :lol:
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Re: carb

Post by gt_james »

The way my choke failed, I just got some clothes pegs to hold the choke out, then took them off as the engine warmed up. You could remove the dashpot completely I suppose and create a new throttle stop, but it would be less smooth to drive without.
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Re: carb

Post by rustyrescue »

so before I start messing I was looking at what is what on this fiendishly complex carb (well the stuff attached to an otherwise simple 4 barrel).
The choke pull in the car operates the choke flap....if it does not self return I can work out what does it and disconnect.
There is also a 2nd cable operated by an electric motor/solenoid which seems to control a fast idle...not sure if it works yet.
Am I correct this fast idle is not controlled by the in car choke lever?
Currently it is a git to start cold, though a little fuel into the top of the carb/airbox and it fires straight up.I think 20 odd years of storage mean the carb needs a strip, clean and check before I do much else.
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