[Kevin H]

This was on a 411 S5, but given the part number it probably applies at least to the 407 to 412.

I recently replaced the rubber bellows on the accelerator link rod (PN 407-1-27008 available from Bristol Cars Services). This bellows provides a seal between the cabin and the engine bay where the accelerator link rod passes through the bulkhead/firewall.

It should be a simple task to replace but is complicated by the fact that it is so difficult to access. I realized that there is a hard way to do this job and an easier way, so I will explain what I did in the hope that it make it easier for others.

I first tried to disconnect the link rod from the accelerator pedal from inside the car, using a light and a mirror to see what I was doing behind the pedal. After struggling for some time to try to remove the split pin behind the pedal I was unsuccessful and decided to disconnect the link rod in the engine bay and bring it through into the cabin. This immediately gave me unfettered access to the back of the pedal so I could remove the rod. There should also be a small spring between the rod and pedal which disconnects easily from the pedal.

Beneath the carpet and underlay where the link rod passes through the firewall there is a round steel plate with a hole in the middle which is fixed to the bulkhead from inside the car with three hex headed bolts. This plate secures the flange of the bellows against the bulkhead. I am pleased to say these bolts came out without any drama, although I had to prise the steel plate away from the bulkhead surface with a chisel (a screwdriver wasn’t sharp enough). It may come away much more easily on other cars but someone had half painted over it on my car and the perished rubber beneath also helped to stick it the surface of the firewall.

Thread the large rubber flange on the bottom of the bellows through the whole in the round steel then insert the accelerator rod though the bellows (if you leave the spring attached to the rod you’ll know for sure you have it the right way around). I used some silicone spray to make it easier to insert the accelerator rod.

Slide the small end of the bellows up the rod to the pedal end and secure it. The old one on my car was secured using a split pin through the small neck of the bellows and the rod, but there were no holes for the split pin in the new bellows and I decided that securing it with a tie wrap would be less risky than trying to cut neat new holes in the bellows.

Insert the rod through the bulkhead and connect it back up to the throttle linkage on the other side. Re-fit the three hex head bolts which secure the metal plate and bellows flange to the bulkhead. I should mention that the three holes in the bellows flange lined up perfectly with the holes in the steel plate, which is a credit to Bristol Cars given that the steel plate was made at least 33 years ago.

Then connect the other end of the link rod to the accelerator pedal using a new split pin and reconnect the small spring between the pedal and the link rod, (it’s much easier to insert a new split pin ‘blind’ than it is to remove an old one!)