Triumph Repair: air/fuel mixture adjustment, zenith stromberg, air fuel mixture

Question
QUESTION: Howdy!
Say, I tried to adjust the air/fuel mix on my 1979 triumph spitfire and found that it seemed to require excessive effort turning the specialized tool that's needed. I used the proper sleeve-guide, etc., but it just seemed far to difficult to rotate so I left it alone until I got further info. Any clues?

Thanks, Jeff

ANSWER: There is a set screw at the base of the air valve, which is meant to be a locating guide for the direction of the needle, but the PO may have put something different, or there may be gummed up fuel in the bore the needle slides in.  Disassemble the air valve, noting all the proper orientations, and clean/soak the air valve until it can slide more easily.  The needle & spring loaded housing for the needle should be removable.




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QUESTION: scott,

i just sent you an email concerning my 1979 spitfire and the fact that it 'pulsed' at idle. i replaced the diaphram and it seems to be much better.

the problem i'm now having as i mentioned before is getting the slow and fast idle set properly. none of my books specifically talks about the water-choke, zenith stromberg car for California. i don't undertsand at all how they're supposed to be set up if everything was screwed up . i need to know how to set it up as though i was a worker in the plant setting the 'across the counter rough settings' up (after linkage was installed of course). i'd sure appreciate your help when you can get around to it.

thanks, jeff

ANSWER: Let me know if you have the haynes book; that is my reference when it comes to tuning this carb.  Like most, I would ditch the water choke if I could, and replace it with a manual cable choke.

If you have to keep the water choke, there is a process to spin the choke to set it corrrectly, but I'd have to research it further...

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QUESTION: i'd love to get rid of the auto choke! what a hassle!

yes, i noted the 'grub-screw' for the needle placement and made sure it wasn't binding...i even replaced it along with a new diaphram and adjusting screw for the needle. there's something else going on that isn't making any sense to me at all. i explained in another message to you the symptoms i'm having. it seems to have something to do with the idle settings being out of whack with each other.

sorry to keep buggin' you about this but i realy need to get this figured out. i know it'd be a lot easier if you could get your hands on the car itself, but alas...

thanks, jeff

Answer
Ya, sometimes I've had the needle assembly stuck in that bore, and can't get it out without al ot of force; not much you can done once some raised edge gets in there other than force it.

I would suspect all the issues are going to be around the idle mixture settings and getting it right in pair with the overall mixture.  Alot of that process is trial and error.  About the best I can offer is to send you a manual choke CD150 I know works for you to try.  You'll still have to set the mixtures, as this was a carb I had on my race car, but...