Electric choke on 400

[Hydroglen]

Could use some help / advice on this one.
The electric choke on my 400 seems a little temperamental lately. This is mounted on the frt carb and is operated by a switch on the panel. It does not appear on 401 cars so maybe just the early cars.
XK 120s had something similair.
I have power and have made sure it is clean and working. The electromagnet works and lifts the piston. I am not sure what adjustment I should make to the little piston and needle next to it.
Perhaps one of you chaps have been down this path before and can point me in the right direction. Pehaps a scan of a tech page?
It has been great for a number of years, so I have no complaints other than lately. Currently we are not happy with each other.
Thanks,

Dorien
PS oil leaks are fewer thanks to your good suggestions.

[Geoff Dowdle]

Dorien ,
I have had little experience with the SU's as I usually use Solex or Weber,
but if the electro magnet is working and the rest of it is untouched ,
it is such a simple device there is very little to go wrong with it .
Read up in the 400 - 403 Workshop Manual section 3 , p33 to 36.
If you don't have a copy down load the pages from Ashley's website
www.jel450.com

Just another point about the triple SU's , a few years ago I had a set of
SU's fitted to my 400 for the first time and had trouble tuning the front
carb .
I found that by accurately checking the float levels of the 3 carbs the
front one was about 1/4 in lower than the others (after setting them all by
the book) .
On further investigation I concluded that the front float and choke device
is designed for side draft SU's and not down draft and is a larger diameter
than the centre & rear.
A simple fix was to bend the brass float fork ,that controls the needle ,
upwards so it is almost straight(bending at the piont where the semi
circular shape meets the horizontal section).
This lifted the float level to a point very close to the others and I was
able to tune it correctly.
I did the same to two other 400's which improved idle and performance as
well.
All those 400's from new must have running with the front two cylinders
lean .

Regards
Geoff

[Hydroglen]

Geoff,
Thanks.....I have the manuals. Could not follow or find how to correctly set
the adjustment on the needle, but by luck or ? after cleaning it is back to
working again.
Cheers
Dorien