Valve centering procedure

I am using a 1986 Musting Pressure Differential Warning Valve ( aluminum) on my GT 40. Does anyone know how to centralize the valve. The information I have advises the following:
1) Ensure master cylinder reservoir is full.
2) Turn the ignition to the ACC or ON position.
3) Depress the brake pedal firmly. The valve will centralize itself causing the brake warning light to go out.

This does not seem to work as the ignition light stays on.
Anyone have any suggestions.
I am using Tilton dual master cylinders.

 

[David Briggs]

You will need to remove the valve from the system, the idea behind the dual master cylinder system is to design in a pressure differential between the front and rear brakes. You create this differential by sizing the master cylinders according to the weight differential, rotor diameter, size and number of pistons in the calipers and tire size front to rear, Tilton has a questionaire that you can complete and one of their engineers will suggest a starting point for the master cyl sizes. On my CAV that recommendation was a 3/4" front m/c and a 1" rear, this sets up your basic front to rear bias and you fine tune it with a balance bar on the brake pedal itself. A larger m/c reduces your mechanical advantage over the piston in the caliper. In other words this set up, with all other things being equal, will apply more braking pressure to the front brakes.
The CAV has the same size rotors and calipers front to rear, other cars may not be set up this same way.

 

Thanks for the info David.
The only reason I am using the differential valve is to get the brake warning light, (integral with the valve); which I think is a legal requirement in Canada for a road car.
I can easily disconnect the valve. Any suggestions for a brake warning light if I disconnect the valve? I will contact Tilton re my M/C sizing, Thanks for that info.

 

[David Briggs]

And here I thought I was being so clever! I wondered why nobody else had jumped in on this one!
It is a shame that Canada treats GT40's the same as a real car, you will probably need airbags and bumpers soon.All that aside, do you need to know if you have actual brake failure or will a low fluid level warning suffice? that would be easy.

 

A fluid level warning would probably get me through the government safety test i believe. Is ther an easy way to install that? A float switch on the reservoir cap would probably work if I can find one that will fit the Tilton reservoir.
The safety test does check for bumpers. I will probably have to make a couple of make shift bumpers for the test, and then remove them. They do not requrie air bags yet thank goodness. The UK has very strict safety requirements for their GT-40 I believe. Do you not have to jump through these hoops in the US?

 

[Howard Jones]

SHSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

[Jim Cowden]

Mike
In Australia we have the same problem.
If you have no pressure switch you must have a level senser.

I am trying to find somthing I can make work & fit in the Girling resivoares.
If you find out it would be nice to now.

Jim

 

Hi Jim.

Have not found anything yet. Will advise when I do.

 

[David Briggs]

On the CAV there is a level sensor on the brake m/c, The cap was the same as the remote cylinder reservoir used for the clutch When I installed the Tilton set up I used the CAV clutch reservoir, not the Tilton part. Junkyards have to be full of caps with float mechanisms, take a reservoir to Pic A Part(or whatever you have there and get one). You could also inquire of Jean and John at Autofutura and maybe they can get you something that will work.

 

[Jim Cowden]

found sensers by RS components RSF50 series.
Easy to fit in lid.
Tryed getting a pic up but its a pdf & im useless.
jim

 

[Ian Anderson]

Is this what you are after
http://www.nfauto.co.uk/cbs_products3.htm

From NF Auto see page 3 about 1/4 way down the page 2 and 3 way fluid resevoirs with level sensors.

Happy Christmas
Ian

 

Hi Ian.
Yes that is what I am looking for. I think I will see if I can find one in a wrecking yard as David suggested. The RS Components switches look like they would work, but size could be a limitation as I am using it in a remote mount Tilton reservoir which is quite small. Will try the wreckers first and see what i can find.