I recently serviced the top section of all 4 ZS carbs, removed
diaphrams and needles and re-fit all the needles with 2.5 turns
anti-clockwise, hoping that all 4 carbs would end up on the lean
side of things.
The two on the right are leanish and I’m happy with that.
Now the 2 on the left are still running rich. What could be
causing the two on the left to still be running rich despite the
mixture screw being max lean (2.5 turns anticlockwise)?
In reply to a message from jagwit sent Sun 17 May 2009:
Philip:
Are you using the proper needles? The wrong needle can make it
impossible to get the mixture right. A European spec 1973 Series 3
requires needle B1CK; a U.S. spec requires needle B1CQ.–
Jeff MacGregor 1971 SIII 2+2
Montclair, New Jersey, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
In reply to a message from jagwit sent Sun 17 May 2009:
Philip
Are the chokes adjusted the same on both banks?–
The original message included these comments:
The two on the right are leanish and I’m happy with that.
Now the 2 on the left are still running rich. What could be
causing the two on the left to still be running rich despite the
mixture screw being max lean (2.5 turns anticlockwise)?
–
Pete Grice 71 S3 2+2 1S50440
Church Lawton, Cheshire, United Kingdom
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
In reply to a message from jagwit sent Sun 17 May 2009:
Hi Philip,
I had same problem due to the enrichment device on one bank
being assembled with the disc inside 180degress
rotated…means overfueling for both carbs on that bank.–
Dave SIII E, Tr4a, Elise, http://www.xketype.com
Georgetown, Penang, Malaysia
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
Fenner
(Ferman Wardell 1971 E-type Series 3 2+2 V-12)
6
Hi, I’m 9 years late coming into this discussion and found it on a search. Same problem: left bank running rich. Am initially going through the mixture adjustment phase and trying to lean out the left mixture until the plugs match the right bank’s plugs’ nice light brown color. I believe the choke is working properly and am interested in the disc positioning. How did your situation turn out?
HI Fenner ,How did you solve your problem ? I have a similar problem, but richer on the right bank. All needles adjusted to the most lean mixture, thermostat compensators checked, choke checked, right needles etc, still CO reading above 7. @jagwit , I know that you have EFI, like i planned to, but did you find the issue with the unbalanced mixture across banks ? And are you happy with the EFI conversion , drivability, CO, economy ?
Thanks,
Rui