Hello Geoff:
Good to hear your positive progress with the SU conversion.
Regarding the flooding that is occurring,if the needle valve and seat were
not recently replaced just replace them both in both float bowls.
Look at your needle valve and seat(float bowl) to see there is no
trash(rubber hose chips caused from taking the hose on and off) in there
causing it to leak when the level should have it closed, just remove the lid
turn it upside down and lightly press on the float and see if you can pass
air from your mouth through it.
Also check that float level is between .126" to.189" I prefer the wider end
of this envelope. adjust the all plastic float with shims under the needle
seat housing and the metal arm type can be adjusted by bending, just keep it
square when it contacts the needle.
If you don't currently have a book like the Haynes Tech book on SU
carburetors and the book from Des Hamill on How to Build and Power Tune SU
Carburetors, I and many list members highly recommend them.
Since you are toying with different needles,You might want to checkout this
SU carb link that on the bottom of the page has some downloadable Needle
selection software http://www.teglerizer.com/sucarbs/index.html one being
revised as recent as last month.
Brooks
Atlanta
----- Original Message -----
From: <Gameparker@cs.com>
To: <6pack@autox.team.net>
Sent: Friday, November 23, 2001 8:50 AM
Subject: HS6 Carb Conversion
> List,
> thanks for your respective replies. I was indeed using a lightweight oil
in
> the dampeners- changing to engine oil as some recommended along with
sorting
> the linkage, did solve some of the problems I was having. Still have
> extremely hard starting when warm, however, but I think I've found the
cause.
> After a run today, I removed the pistons to change to the richer BAX
needles
> that were supplied with the carbs on purchase (incidentally, engine runs
MUCH
> better with the BAX needles no 2500-4000 rpm hestiation now). When
lifting
> the piston/needle assembly out, petrol started to gush and spurt out of
the
> jet and flooded the carb body at an alarming rate. Duplicated this
situation
> many times. This is probably what is causing my hard starting when warm.
I
> immediately disassembled the front carb and it was fine, no flooding. Why
do
> you think that this is happening to the rear carb only? If the fuel
system
> pressure was too high, it would be happening to both carbs (incidentally,
I
> am running the stock mechanical fuel pump). List, your collective wisdom
> please, as I've sworn not to touch the carbs without hearing from you
first!
> Cheers and Regards
> Geoff
> P.S.: Sounds obvious, but pump not running when this happens!
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