THE INTERNATIONAL JAGUAR 'S'-TYPE REGISTER FORUM

Alan,

On the top of the float chamber, there should be a "tickler pin", ( spring loaded) which when pressed down, pushes the float down and allows more fuel to enter the float chamber. One of the members on here thought the earlier cars had a "tickler pin" on both carbs., and later cars had it on only one of them.
Hope this helps.

Richard

Alan,
Many of our cars are not fitted with any tickler pins. You would have to retrofit. My car has none & I know of many, many S Types without them on both carbs.

Thanks Richard and Glyn,

I'm a non-tickler guy. That looks very similar to the lift pin setup for the pistons.

Alan

Alan
The setup is indeed similar to the piston lift pins as you mentioned. Enabling the parts to be used for both jobs is an arrangement offered by Burlen Systems the present owners of S.U. The images recently listed in this thread show quite clearly where these tickler pins fit in the float chamber lid.

Both S Types and Mk II early engines had at least one Tickler pin at some stage of their production and most certainly in carburetter sets AUD154F and AUD154R. These sets were listed for 3.8 ltr engines with oil bath air cleaners, however I have converted a number (at least six) all of which had paper air cleaners and fitted to 3.4 ltr and 3.8 ltr engines. I put this down to typical mid 60s need to fit what was in stock during labour disputes. The only real difference between oil or paper air cleaner carburetter sets was the main needles, easily changed on production.

Currently float chamber replacements for Jaguar S Types are cast with a blank to drill and fit a tickler pin if required, this enables the lid to be used with or without a tickler pin.

Elimination of the Tickler pins from all engines during the 60’s would most probably have started to occur with NADA USA Federal requirements on air pollution. The fact that your engine does not have tickler pins does not surprise me, particularly if the car was produced around or after 1965 or delivered to a hot climate area.

Nevertheless, tickler pins are a good diagnostic tool and worth fitting, and like insurance, nobody is interested until circumstances dictate they are needed.

isFull disclosure here. When I bought my 1964 S Type (P1B75188BW) in 1976, it was sporting a 4.2L E Type engine with Strombergs. The fellow who encouraged me to buy the car owned about a half dozen MK2s, most in non-working condition, so I bought a 3.8L engine out of one of them, rebuilt it and put it in my car. I don't remember what year his car was but that is where I got my SUs, sans ticklers.

I showed my car for a number of years with no comments about my engine from the judges when one day, a spectator said "I thought the oil filter on the S Types pointed down not up". Oops. After looking into this I realized there were additional differences between the two engines such as aluminum sump vs. stamped metal. I sourced a correct engine and then it only took me 20 years to get around to rebuilding it and installing it when I restored the engine compartment for the third time. Now you know. Maybe my car when new had ticklers, I'll never know. The carbs on my car each has a boss on the float chamber cover like in Glyn's photo. I assume the recess is to facilitate drilling out the boss if someone ever wanted to install a tickler. Live and learn.