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Mark Herbstreit
Prolific User
Username: mark_herbstreit

Post Number: 140
Registered: 5-2005
Posted on Monday, 15 February, 2016 - 21:39:   Edit PostDelete PostView Post/Check IP

My Turbo R brake pedal feel was not right. Spheres were replaced and plenty of brakes available but a fairly hefty unnatural push was required to get the desired result. Years ago my Shadow II had brakes that were either on or off with nothing in between. The problem was solved with the replacement and adjustment of the Brake pedal feel cone.
I decided to try the same job on the Turbo with complete success. The pedal now has a soft progressive natural feel.





The cone is between the two circular disks on top. The manual gives adjustment on the cone and the spring to the upper right. This is the rat trap in its simplest form having done away with the master cylinder of the early Shadows and G valve of pre ABS cars.
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Robert Noel Reddington
Grand Master
Username: bob_uk

Post Number: 874
Registered: 5-2015
Posted on Wednesday, 02 March, 2016 - 08:37:   Edit PostDelete PostView Post/Check IP

The rat trap shown is much simpler than the Shadow 1.

It's a shame that Crewe didn't put an inspection hatch in the floor for easy access to the top of the mechanism. 8 inches long by 4 inches wide should do the trick. Especially if the floor has rust holes already.

Recently I had to check out my master cylinder over travel warning light switch and wiring which is above the master and neigh impossible to get at. Eventually I managed to connect the test probes. I did think about cutting the floor above and making a nice bolt on cover with little turn ups on the edge for strength. It's under and inch of carpet and under felt so invisible.

I know the feeling of a failed cone. It's like my Shadow with loads of air in the master. Except your pedal does not go down so far. Mine goes down and the power brakes come on it's difficult to judge braking and it's either on or off. Hard to modulate.

A mate had a master pop on at T1 Bentley so we wrapped the safety stop spacer with tape to get the pedal up higher and he drove the slowly home for 10 miles. He said the pedal felt 'king awful.

Might as well oil the mechanism while it's out. Maybe repaint the frames. This is why every job on my car takes so long I do unnecessary work. Still it keeps me off street corners
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michael vass
Frequent User
Username: mikebentleyturbo2

Post Number: 95
Registered: 7-2015
Posted on Wednesday, 02 March, 2016 - 20:57:   Edit PostDelete PostView Post/Check IP

That looks ahell of a job to remove, and refit!
How long does ot take?
Well done
Mike
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Mark Herbstreit
Prolific User
Username: mark_herbstreit

Post Number: 144
Registered: 5-2005
Posted on Wednesday, 02 March, 2016 - 21:25:   Edit PostDelete PostView Post/Check IP

It is fairly straight forward. The cover itself has a ridiculous number of retaining screws all covered with underbody tar that took as much time as removing the rat trap itself. Also the hydraulic line connections run close together so you need to have the correct brake line spanners to undo without vandalising. A pinch bolt on the brake pedal required a second pair of hands to wiggle free and then reset in the correct position, but otherwise OK. A full bleed was needed upon reassembly but all straight forward, not rushed and done on a Sunday.

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