Hi all, my first post as a new member. I really hope and I will endevout to help others in the future but for now I need a little please.
Xj12 1988 GM 400 GEARBOX....There is a cover opposite side to where the speedo cable enters the box. Behind the cover is a spinning thing...Great description I know.
It seems it may be centrifugal. It started clicking as the wheels turn. Does anyone know....
- what is it exactly

?
- should the wings(best word) be spriing loaded
- does oil splash or pump around it therefore should cushion and prevent clicking as each wing falls under gravity as spins? If so, maybe lack of oil due to old filter not getting there? Oil level is good!
Hours of searching as left me frustrated. But the great thing is, it lead me here. And now I'm not alone anymore.
Any help is massively appreciated.

 

That is the governor and its position is affected by the speed of its rotation, it affects the points at which the gearbox changes gear. Yours looks fine to me, the "wings are indeed spring loaded.
What is the problem you are trying to solve?

 

Hi Greg, thanks for replying. A few days ago a clicking noise started as I drove. After much searching I have found it is the governor. As it turns the wings towards the bottom opens and clicks as it does so, making a clicking noise. I'm curious to why all of a sudden it can be heard.
should oil be aroumd the area to cushion the noise maybe?

 

Or, should the springs be stronger so the wings can't just fall maybe???

 

Maybe the springs are getting weak? You can rebuild the governor, or buy a replacement item, but the Jaguar calibration may be unique. The lighter the weights the higher the engine will rev before changing up. Typical rebuild kit, you just use the bits you need:
https://www.summitracing.com/parts/bmm-20248

You DO need to know what you are doing though, before messing about with modding the gearbox.

 

Thanks for this. I've got the governor out and stripped.
I feel there is a spring missing somehow....from under the piston ibsuspect. Both are there for the wings, but as I mentioned, the wings have no resistance to opening, so there must have been a 3rd spring....maybe not under the rod but if not, I have no idea..
I'll keep the weight as is, because apart from the recent clicking noise , she ran fine. Strangely enough.
If you have any more thoughts that would be great. Cheers

 

Craig, any luck getting this sorted out? Was it a missing spring?
Bill

 

Hi Bill.

Yes, eventually I came to understand how it works. The resistance is purely hydraulic. So I am hoping once a new filter arrives and I fit it, more oil will flow and the governor won't be starved and prevent the 'slapping' of the wings.
I'll post the result.
I also found a good YouTube video where someone had cut a section through one to explain the function.
'Hydraulic Governor operation explained '