Help with VR brake master cylinder

[Helicopter]

OK, one for the experts!
VR V8 with ABS and PBR 15/16 master cylinder.

Braking is not very good, and under hard braking, pedal is very spongy for the first part of its travel, then you can feel a clunk as it hits the secondary piston within the master cylinder, and pushing further does little to increase braking.

Brakes pads are new, no fluid leaking and have been bled.

I rang holden, who informed that they do not stock the master cylinder nor a seal kit for the VR anymore So I asked them, what does a VR owner do, sell his nice car because the master cylinder is no longer available?
Not suprisingly, there was dead silence from Holden.

Rang another two independant workshops who also confirmed this.
Then rang Repco, and they appear to have a seal kit to suit ABS, but costs $150. There is also a minor seal repair kit at $50, but they are not sure if it is suitable for ABS

I'm just going around in circles here. I don't trust getting one from the wreckers for obvious reasons.

Does anyone know where I can get the correct seal kit, or worst off a complete new master cylinder?

Cheers

[hako]

An expert I ain't, except for putting my foot in my mouth.....however, I'd try the brake specialists like Brakemart etc - in Sydney there would be quite a few. Maybe you could "upgrade" to the 1" VT master cylinder which also gives a higher pedal.
Re ABS - I was under the impression that ABS/non ABS master cylinders were identical except for 2 ports being blanked off with a plug.
Are you sure the problem is a bad cup in the M/C and not air trapped in the ABS which apparently you need a Tech 2 tool to cycle the ABS to bleed it out.
Thats my guesses. Good Luck.

[08sky_way]

I have just wasted $180 on a new master cylinder (car does not have ABS), and purchased it from AutoOne. I had trouble bleeding the brakes and was convinced by the experts that the problem would be in the original master cylinder - but it wasn't, and I have a spare perfectly good master cylinder. The new unit wasn't easy to bleed either. I'm told by a mechanic that bleeding brakes with ABS is more difficult than systems without it, but have no experience with ABS. IBS Brakes (Independent Brake Supplies of Guildford NSW Tel 02 9892 2166) were the suppliers of the new master cylinder that was made in Taiwan.

[ephect]

if you get an airlock in the ABS unit, you'll need to take it to holden or somewhere that has a tech tool (tech 1 or 2, cant remember). that tech tool can purge the ABS unit to bleed the air out.