The following warnings occurred:
Warning [2] Undefined variable $search_thread - Line: 60 - File: showthread.php(1617) : eval()'d code PHP 8.1.31 (Linux)
File Line Function
/inc/class_error.php 153 errorHandler->error
/showthread.php(1617) : eval()'d code 60 errorHandler->error_callback
/showthread.php 1617 eval




Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Setting SU Mixture
#4
(26-05-2018, 04:35 PM)John P Wrote: Hi,

I have an "Ulster" replica with a 1 1/4" SU Carb from a Morris Minor (I Think) with an AN needle which is fed from the scuttle tang by a 6 volt SU pimp.

I have set the timing to TDC fully retarded, it's a later DK4A distributor, but have always had problems with starting.   Mo matter what the weather it needs full choke to have a chance of starting but on the road seems OK.   However if you switch off re-starting is sometimes fine but more often problematic.

To try to resolve the starting issues I have dismantled and fully cleaned the carb, re-checked the timing, added fresh petrol, and made sure the float level is correct.   However, when I try to adjust the mixture at tick-over I can turn the jet up and down around two turns with no real effect on the running.

The plugs are normally black so it looks as though I need it very rich to get started but then it's too rich for normal running.

The engine was completely re-built by me a few years ago so I don't think there's any problems with compression etc and, as far as I can tell there's no leaks in the induction tract.

Any suggestions why I can't seem to adjust the mixture correctly?

John.

Hello John,

Is your DK4A set up with electronic ignition?

It makes for easier starting and no more problems with stale pet4ol.

Charles
Reply


Messages In This Thread
Setting SU Mixture - by John P - 26-05-2018, 04:35 PM
RE: Setting SU Mixture - by Chris KC - 26-05-2018, 06:17 PM
RE: Setting SU Mixture - by Ian Williams - 26-05-2018, 09:42 PM
RE: Setting SU Mixture - by Charles Levien - 31-05-2018, 11:15 AM

Forum Jump:


Users browsing this thread: 1 Guest(s)