Brake caliper Wiper Seal Retaining ring

[nickr]

Having just destroyed 4 retaining rings in one swoop on just one piston, just wondered if anyone as any little tricks on getting the damn things in without wrecking them.

I think I read on another post somewhere that someone recommended getting serveral repair kits because of the failure rate getting the retainiers in - now I see why.

First three pistons went fine , but the last one in the caliper is causing a real problem and i've already checked for bore damage which might cause it to distort when going in.

I'm even doing it similar to that shown in the dender repair manual, using a g clamp and metal disk to pull it in evenly.

One though it did have is to try putting them in before the piston is in the bore???

Any thoughts / tips

Thanks

Nick

[Les Henson]

I did a thread in the archive on rebuilding a caliper. I used a socket to get the retainer in, but still managed to ruin two in the process. Mike Gemini posted a while ago that he used the piston part-way in the bore to act as a guide. The damn things are just too fragile.

Les.

[nickr]

Thanks Les... looks like I'm doing everything right. Hopefully it one of those jobs that inexplainable proves to be a pain one day, then after a nights sleep goes ok the next day.

Ralph, don't know if you are online, but would you know if it is likely that Bob at LRP carries stock of the repair kits.. (aeu1547).

My guess is he does so I think I'll probably be relieving him of a few kits today !!

Regards

Nick

[Tonk]

i do it with the piston in the hole

best way i found was to have the piston sticking out a few mm's and use a collar to slide over the piston (this holds everything central) then G clamp to pull retainer in place

[Shox Dr]

I've just rebuilt all 4 calipers on my 90. I started out with a kit from Britpart or should that be Britpart. I managed to flatten the first 4. Got hold of a set of OEM ones and they were worlds apart in quality.

I used a large socket and a swift belt with a hammer, and all but one slid in, then installed the piston.

[JimAttrill]

Don't even attempt to use the ****part ones. The retaining ring is sort-of a quarter-circle in section whereas the OEM AP Lockheed ones are a half-square. The Bearmach ones are OEM, or at least look at the packet to see if it has AP or Lockheed on it.

The way I get them in is that I use a steel ring that exactly fits over the piston. It is the inner of a taper-roller bearing that I found on the scrap heap. For the larger 110 pistons I use a metal ring that I think was a hub spacer from a TD5. It helps to have boxes of junk lying around

[western]

Thanks Les... looks like I'm doing everything right. Hopefully it one of those jobs that inexplainable proves to be a pain one day, then after a nights sleep goes ok the next day.

Ralph, don't know if you are online, but would you know if it is likely that Bob at LRP carries stock of the repair kits.. (aeu1547).

My guess is he does so I think I'll probably be relieving him of a few kits today !!

Regards

Nick

I'm sure Bob will be able to get as many as you want, I'm back home on Sunday 21st.

just remembered I've got a load of spare rings at home, but not much use to you today.

[Dunc]

Not wishing to be a smartarse (no, really i'm not) but if you've flattened the rings fitting them you're doing something wrong!

When i rebult the calipers on the Rangey, i put the bottom seal in, rubbed a bit of fluid around, put new pistons in and then put the top seal on.

Then, making sure the ring is sitting square, put a 2" square of plywood on top of the ring, attach a g-clamp and slowly compress the ring into the caliper body. Because you've already checked the ring is sitting square, you can't fail but put the ring in the right place without rubbishing it up and it just pops neatly into place.

Because they're a press-fit, blatting it with a hammer definitely isn't the way to go!

My little bit of ply lives in my toolbox because it makes doing caliper seals a doddle.

Also, it's worth running some scotchbrite around the top of the caliper to make sure there aren't any tiny bits of smeg there to stop the retaining ring dropping into place. Careful you don't get it in the bore and scratch it though.

Best of luck, once you've sussed it you'll do 'em for everyone!

[JST]

I fit them slightly differently

i fit the dust seal first with no piston in there by using a large socket (impact one as it has a thicker wall) and pry it down with screwdriver/pry bar against the opposite side caliper body.

i then fit the lower seal and then the crud seal. seems to work OK for me. lubricating the seals with brake fluid first. then sliding the new piston in to finish.

[nickr]

Thanks for all the replies to this thread guys with loads of good ideas.

As predicted, the following night when I tried again, everything went fine. I did things in the normal manner, lower seal, piston then the wiper seal and retainer together using the piston as a guide. Used a G clamp ,and a very nice round disk of 5mm steel plate, which incidently was the waste product from cutting the winch bumber to install 2 swivel recovery eyes. It is perfect size, and is now going to remain as a special tool!

I think if I could identify anything that caused my problem initially it would be the use of the G clamp. 3 of the cylinders are easy to do because the outside of the caliper is flat. The 4th is more difficult because of the casting of the brake pipe port. This caused the clamp to skew, and I think caused the problem. I mounted a flat piece of 4x1 wood in the jaw of the workmate, which can be used to push the caliper against and provides a flat surface for the clamp.

Also I took the advice to get the OEM seal kit. The kits I had before where not Britart but Karson??? i think from Paddocks.

As a matter of interest I thought I would measure the thickness of the metal retainers as the Karson and OEM looked pretty much identical. It actually turned out that the Karson ones were marginally (0.02mm)thicker!! - I used a micrometer - sad I know!!! That said the OEM rubber seals looked better.

thanks again

Nick

[Lars L]

I've used the Britpart kits for the front of my One Ten. B)

Only problem, and luckily I checked before taking things apart, was that a couple of the metal rings and rubber thingys were considerably smaller than the rest.

After contacting my supplier, I got new kits FOC. With mixed size contents, just like before... Well, I had enough to make up a suitable kit.

Getting the metal rings in place was no problem at all. A piece of flat iron and a C-clamp, "klick" and they were in place. Just lucky, perhaps.

[Dunc]

(0.02mm)thicker!! - I used a micrometer - sad I know!!!

Dude, i'm with you.

I regularly tell people it's not sad, it's attention to detail.

B)