#1 Bulkhead Throttle Eccentric Sleeve
Posted: Thu Jan 22, 2026 3:50 pm
Further to my previous post, (Throttle linkage assembly and bulkhead bush), on my friends 1966 RHD 4.2 FHC 2+2, we have now fitted a new bush into the bulkhead bracket which has removed any excess movement of the rear slave shaft in that bracket and firmed up the throttle linkage to operate more effectively. Many thanks to Sean, (40GT) for the guidance on gently lifting up the wiper motor to gain access to remove the hidden second bolt on the bush bracket.
We are now working on balancing the three SUs. We have reset the three SU throttle butterfly valves on their spindles to ensure they are all fully shut as the previous worn bush provided excess movement, undone the choke cable and set the slow running screws at 2 turns out and finally after setting the jets flush and turning them down 2 1/2 turns, we proceeded to try to start the car. The car simply would not start - it was a cold and wet day - until we reluctantly reattached the choke cable and applied some choke. Once up to temperature, by adjusting the slow running volume screws with a carburettor synchroniser we managed to get all three to draw the same amount of air.
The question is, what is the role of the eccentric sleeve on the throttle linkage on the bulkhead and where should that be adjusted to during the initial setting of the carburettors, as this effectively moves the whole throttle linkage to all three carburettors to give either more or less throttle movement on the butterflies ?
This is my bulkhead eccentric sleeve on my car which is operating triple Weber DCOEs, but the same principle applies to the standard Jaguar linkage.
We would welcome any observations please.
Regards,
Dave
We are now working on balancing the three SUs. We have reset the three SU throttle butterfly valves on their spindles to ensure they are all fully shut as the previous worn bush provided excess movement, undone the choke cable and set the slow running screws at 2 turns out and finally after setting the jets flush and turning them down 2 1/2 turns, we proceeded to try to start the car. The car simply would not start - it was a cold and wet day - until we reluctantly reattached the choke cable and applied some choke. Once up to temperature, by adjusting the slow running volume screws with a carburettor synchroniser we managed to get all three to draw the same amount of air.
The question is, what is the role of the eccentric sleeve on the throttle linkage on the bulkhead and where should that be adjusted to during the initial setting of the carburettors, as this effectively moves the whole throttle linkage to all three carburettors to give either more or less throttle movement on the butterflies ?
This is my bulkhead eccentric sleeve on my car which is operating triple Weber DCOEs, but the same principle applies to the standard Jaguar linkage.
We would welcome any observations please.
Regards,
Dave
