I have read that if you are replacing the disc calipers and hoses once the brake fluid reservoir empties you are stuffed BUT if you depress the brake pedal fully to the floor whilst doing these the brake fluid cannot flow out of the reservoir via the master cylinder. Is this true or just BS.

I am going to change the calipers and brake hoses all round and I don't want to have to bleed the brakes from scratch by activating the shuttle valves in the ABS modulator as I'll use my pressure power bleed kit once they have all been changed to flush the system through.

Problem is my Autel Maxidiag 712 cannot activate the ABS modulator shuttle valves and I'd need to invest big bucks in a Nanocom or Hawkeye.

Any thoughts on this would be very helpful.

 

If you get the Autocom for under $100 you can bleed the ABS and the lines. I just did mine a few weeks ago after replacing the Master Cylinder and it worked great.

Otherwise I read somewhere about jumping the connections where the relay is to activate them.

 

Probably not BS.
My Disco II brakes where always mushy.

 

if you hold the pedal nothing else can go thru the master, its the same s holding the pedal down while bleeding

 

Thanks guys, it's what I wanted to hear. It saves me having to lay out hard cash on a Nanocom, Hawkeye or similar and I can wedge the brake pedal down and change the calipers, brake hoses etc and bleed the system, in fact prior to swapping out the parts then bleed again afterwards to ensure it's all flushed through properly without any air in the system.

I think I'll do the front axle seals and rear axle O rings whilst doing the braking system also and give me a chance to check out the CV joints as well.

Just checking out prices and the TRW calipers are selling at a reasonable price so hardly worth struggling to rebuild/refurb the existing calipers so they can be shelved for spares. Ironically, caliper carriers are nearly as expensive as calipers.

 

I’d love more info on the Autocom please. Where can I buy one?

 

The Foxwell NT510 does the brake bleed also. I got mine used on ebay for $80

 

That's a steal for $80!!!

 

Jumping the ABS relay is about as simple as it gets, at potentially no cost to you if you have a spare appliance cord, or similar - any 2 lead wire would do. There are write ups on here with photos.

I’ve found that the traditional bleeding of the brakes works, yet not ever as good as activating the power bleed via ABS.