Brakes

[cabrioman]

I have the Marlin supplied hydraulic pedal box on my factory built Hunter (Cabrio) which has a servo and master cylinder supplied originally by Marlin. It is the same servo and master cylinder which Patrick had fitted to his Sportster which I think he ditched in the end.

Does anyone know part numbers for these items, I am doing a rebuild on the car and intend on renewing all the brake systems as they are over 12 years old and have done circa 75K.

There are Metro servos on eBay at the moment but the numbers don't match the numbers on mine (LBDHZC014A), I obviously don't know what this originally fitted. I understand the highest boost ratio was the servo fitted to the Metro Turbo but they are probablly like hens teeth.

Are there any other options which will fit onto the Marlin pedal box, I would ideally like to improve the servo boost but at worst need to make sure I don't end up with less.

I do have a modified sierra pedal box and servo setup which I could use but it is a fair bit of work to make it fit as the chassis was built to take the Marlin pedal box. I was looking for a simpler solution which gives good feel to the brakes so you don't have to be Arni to stop it.

Any experience on the best solution? I know there has been a lot posted on the problems with the Marlin servo setup regards leaks and the quality of the pedal box. I have already found some of the bodges on the car when I took it all apart, some of the build quality is quite frankly shocking given the fact that the car was around 25k when new.

Any wisdom appreciated.

John

[Patrick]

I'm still using the metro servo that came from Marlin. The master cylinder is a BMW one attached using an adapter plate supplied by Marlin.

It was the clutch master cylinder assembly I changed. It was originally using the BMW one but the mount system on the side of the pedal box was not stiff enough.

I now have a Willwood master cylinder sitting in an ali Willwood mount. It's now bolted to the scuttle which I've also re-enforced.

The pedal box itself did flex so it has two extra steel plates welded to each side to stiffen it up.

Also my pedals run on bearings rather than the plastic stuff that came with the box. Makes everything run completely smoothly :)

The servo could be a bit more effective as you need to stamp on the brakes pretty hard but you just need to remind yourself you're not in a bit soft easy to use tin top :)

[cabrioman]

Thanks for the info Patrick.

I think the master cylinder I have may be a ford unit as it was supplied by Marlin way back before they went down the BMW route. All the brakes on my car are Sierra so putting a BMW master in the equation would just complicate things further.

I may take another look at fitting the Sierra pedal box and converting it to hydraulic clutch to operate with the M20. I know it fits (just) as I had it on my previous Cabrio and Simon has the same setup on his.

Maybe I am just being a bit lazy, I guess the extra work would result in a matched brake setup with a proper size servo as it would be as the original Sierra donor setup.

John

[Chris Cussen]

Hi John,
My cabrio uses the serria master cylinder/servo and the brakes seem fine.

If you go that route thoug you will, as you know need to make up something for the hydraulic clutch.

Chris

[cabrioman]

Hi Chris

Hope the engines working out OK.

I had a look at converting to the Sierra servo at the weekend. It turns out to be somewhat more involved. I thought I would just be able to plate the bulkhead to close the hole where the Marlin pedal boxcomes through the bulkhead and then fit the Sierra pedal box and servo.

Turns out the chassis has slight differences in other areas such as the column comes through the bulk head in a different position, it is much lower on the Hunter chassis. I had assumed the chassis would be identical bar the layout for the pedal box but it is not.

In the event I managed to pickup a new metro servo from ebay last night for £15.00 which seemed a good deal, so will set the brakes up with that and the new discs etc.. and see what it feels like.

Regards


John