Brake Caliper Pistons

[roverrescue]

Soooo
One of my rear caliper pistons is a little less mobile than factory specs

In lets just say "a few hundred thousand kays" between numerous coiler landies I have only replaced brake pistons and seals a few times - but having said that this fender gets a tough life on the beaches and in the scrub

Ill put a new set of seals and pistons through the whole vehicle just because BUT should I go with stainless pistons or just the chrome plated?

Cost is not stupid different between the two options if buying ex UK just wondering if anyone has had this dilemma?

Will save the $ for important things like beer if its not really worth spending

Steve

[Blknight.aus]

I wouldnt bother for 2 reasons

1. you could easily turn up the SS pistons at a fraction of the cost.
2. if the piston wont rust because its stainless then the cylinder will anyway and you're back to square one with either slow pistons or leaks.

[JC Rover]

I just put stainless pistons in my front calipers. The piston bores were fine and the caliper itself wasn't that corroded. I drive and camp on the beach a lot, so it was the only choice. Once the pistons corrode, and you go to change pads, pushing the pistons back into the bore, the corroded piston surface rips up the seals, causing leaks. I'm hoping this won't happen with the stainless pistons. Just have to do the rears now. Does anyone know if the rear pistons are the same size as the fronts on a 02 Defender?

Jono

[JC Rover]

I just replaced the pistons in my rear brake calipers as one was siezed. For a 2002 defender, the piston is the same size as the front 46mm x 31mm. For what it is worth, the Britpart kit is rubbish. The pistons are OK, but the seals don't fit. I got two to fit, by pressing them in, which they advise against. The other two I just used the old seals. So now I am ordering the stainless pistons and the OEM seals from UK, as Australian suppliers want to rip my arms off!!!!

Cheers

Jono

[uninformed]

Steve, I went for stainless for a couple reasons. #1 ease of buying: It is easier for me to buy parts from one place and pay for shipping once. Going by what they had available I went s/s because IMO I couldnt be sure of how good the chrome plating would be on the non-genuine pistons. #2 price: For the cost of a full set of s/s pistons with seals (EAC brand) to do my entire 110 (12 pistons) and also getting genuine LR seal kits, I figured it was worth that combo and still cheaper than buying kits in Oz. Dont even bother pricing genuine LR from your dealer. (I already did :D)

BTW Dave, let me know when youve finished turning up your S/S brake pistons.....good luck with that :angel:

[redrovertdi]

I did the full set in stainless 4 or so years ago after only getting 12 months out of replacement steel ones, yes i do a lot of beach and scrub and try to clean as much as possible. Havent had an issue since fitting stainless. I to purchased from the UK[still waiting on zeus engineering to get back to me with a price!]

[uninformed]

I did the full set in stainless 4 or so years ago after only getting 12 months out of replacement steel ones, yes i do a lot of beach and scrub and try to clean as much as possible. Havent had an issue since fitting stainless. I to purchased from the UK[still waiting on zeus engineering to get back to me with a price!]


Regarding the steel replacements you used, were they genuine LR replacement pistons? Im guessing not. At another guess, id say the genuine LR pistons are ok, but will be alot more $$$ than good quality EAC stainless steel.........

[redrovertdi]

They were purchased from MR[and this is not a complaint against them or the product, if i had known how long they would last i would have tried to source stainless earlier/from them at the time], they just didnt last but i was doing a lot of beach work, it makes sense to go stainless in this application for what my car does.
Richard

[roverrescue]

Gotta get onto them rear calipers... leaky leaky
anyways- shear laziness here.
Would anyone care to share links for SS pistons and seals from UK
pm if you prefer

S

[uninformed]

Shop 4 Auto Parts | C/PISTON KIT STAINLESS DEF 110 46mm FULL SET (http://www.shop4autoparts.net/Defender/Brakes/Discs,Calipers-&-Drums/cpk12801st-c-piston-kit-stainless-def-110.html)

remember that price includes VAT, we dont pay it. It was 79.15 pounds for me + shipping. That kit will do a complete 110 front and rear. If you are emailing them for questions, tell Simon Serg sent you :)

Im very happy with their service after 2 good orders

[rick130]

Thread hijack !

Serg, their 606665 CV's are cheap !

I wonder who makes them ?

[uninformed]

Email them, they have been happy to give any information where they can.

[Lotz-A-Landies]

Just improving my Defender knowledge.

Are the Defender (pre Puma) 4 pot 46mm pistons or something else?
Are the ventilated rotor Defenders the same size pistons.

Am assuming the rear are 2 pot 31mm pistons?

Diana

[uninformed]

I can only say for my 1998 110 Tdi it was 46mm front and back, 12 pistons and you need 3 seal kits. 1 kit does both rears, 1 kit each front.

[Lotz-A-Landies]

Here it gets confusing, I have a 1991 Defender, but am fitting 1996 callipers and ventilated rotors.

For the rear axles (2), we are converting to disks from drum and may not use standard calipers so need to work out the braking forces. Am considering using ventilated rotors on all six wheels and therefore different callipers.

[uninformed]

As I said, for my 1998 110 tdi (4 pot front, ventilated rotors, standard 2 pot rears, solid rotors) all pistons are 46mm.

I think 90 rears may be smaller but can not say either way.

For what you may or may not use......I have no idea

[roverrescue]

tee hee hee
thanks for the thread bump Diana
Update from my initial question 13 months ago

I now have the seal kit and a set of new hoses in the spare parts bin
Never bought slugs for the pistons - still deciding I guess - hmmm spose I should buy them as by the time I pull these calipers down Im not going to want to put crusty old slugs back in...
My understanding is 12 x 46mm slugs needed for a deefer with factory discs all round (1993 ish onwards)

Have topped up the fluid a few times - Its on the list I promise

S

[Lotz-A-Landies]

The issue is that my Defender 6X6 was a UK build and has never been registered in Australia, the importer/previous owner took the vehicle apart and died before reassembling it.

Therefore I am required to have an engineers certification of compliance for registration and the engineer wants to have the specs of an equivalent 6X6 certified in Australia. The most common Land Rover 6X6 that has been Au certified is the Land Rover Perentie 6X6 which were originally disk front / drum rear, but have now been converted to 6 wheel disk. If I can make my braking at least equivalent of that I'll have no problems.

I know the PBR booster model and am working on getting the PBR master cylinder part number, but it seems the Perentie 6X6 used 4 pot Land Rover 90 callipers on the rear. So I actually need to know the piston sizes on early Land Rover 90 front callipers. (They are a different part number to the 110 or Defender front callipers. (I am also likely to be using ventilated rotors all round.))

[rick130]

Diana, the PBR M/C # is in a thread I started somewhere, IIRC Brian posted the numbers.

I'll do a quick search.

[edit] This thread may or may not help, it just confused me in the finish http://www.aulro.com/afvb/isuzu-landy-enthusiasts-section/131420-perentie-4x4-6x6-brake-m-c-same.html

[Lotz-A-Landies]

Hi Rick

I've been doing a lot of research in the last 36 hours and also brake calculatons.

Still don't know the PBR part number, but have worked out the m/c bore is 33mm and the RTC4998 and RTC4999 Defender 90 calipers have 4 X 41mm pots.

The confusing issue is that the front:rear balance is 0.66:1 which seems very high. My other issue is the lack of load sharing on a 6 coil spring 6x6 and what is the impact on braking. Not issues for the Perentie 6x6 which has load sharing leaf springs. Looks like I'm going to have to seek technical info on bogy axle truck braking.

Diana

[uninformed]

how are you calculating front to rear balance?

[Lotz-A-Landies]

how are you calculating front to rear balance?In these initial calcs, only using piston area, 2 pots in each 4 pot calliper and then adding the two rear axles together compared against the front axle.