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Speaking of carburetion problems ???

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PAUL161

PAUL161

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When I start the 72 "B", it runs like it can't decide if it wants to run or shake itself to death. But after about two minuets it starts to smooth out and run and idle good. After the temp gauge starts to move it runs as smooth as silk. Is this normal?? It's worse in cold weather. For authenticity it has SUs on it now. It didn't do this when I had the Weber on it. /ubbthreads/images/graemlins/hammer.gif
 
Did you check your strangler? /ubbthreads/images/graemlins/yesnod.gif
 
Likely ain't stranglin' quite th' way it should. Linkage is "the usual suspect".
 
Yup, Sounds like the Choke adjustment is off.
Male sure that when you're pulling the cable that the screws are contacting the cams on the throttle shafts and bumping up the idle a bit. If they're the HSs with the exposed enrichment tubes, you can also check to see that they are being pulled down when the cable is yanked.
 
"YANKED"?!?!

Sounds hurtful.
 
Thanks guys! Will check this out today. I've owned and worked on a lot of cars in my time, but this is my first experiance with SUs,(HIF-4s). It just boggles my mind wondering how a pair of carburetors with such a simple design could be such a pain in the _ _ _ (neck) to set up. Paul /ubbthreads/images/graemlins/hammer.gif
 
It's a 'skill test' to put the carbs on with the linkages in the proper alignment if you've not done it before. Best to slack off all the adjustable bits, then go through the setup as "The Book" (Bentley, Haynes, AutoBooks, etc.) explains it. Like anything, after the first time it gets much easier /ubbthreads/images/graemlins/wink.gif
 
Paul, FWIW, I always start work on the carb farthest from the fuel delivery...I get it set up correctly & then move to the one closest to the fuel delivery line.
 
Guess What!!! I took all of your advise. I started from scratch. The choke ajustments were off a very slight amount making the front carb lead the rear carb in idle adjustment. So when I pulled out the choke, the front carb was doing more work. I rechecked the carb balance with a meter and they are now right on. I also found that the mixture was a little lean and made a slight adjustment in that department. She's running better at idle and at high RPMs. This web site is the greatest! A wealth of information from all over the world. Thanks again for easing the pain in restoring this little piece of British handywork. Paul /ubbthreads/images/graemlins/nopity.gif
 
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