Page 1 of 1

Caliper re-build?

Posted: Thu Oct 28, 2004 10:13 am
by Airhead
Next for my car is to fit the breaks as the previous owner gave them to me in a box with the car saying that it failed the MOT as they were binding (amongst other glaringly obvious problems!).

This is down to the old chestnut of a cast iron caliper and alloy piston and rust in the bore I presume so I've got some seal kits and intend to take the pistons out and polish the bores and pistons.

Had a go at removing the pistons from one of the calipers last night using an old master cylinder and yes there was some rust but they're not easy to remove! On calipers I've re-sealed in the past onve they're free'd offa bit you can usualy pull them out with your fingers......these are tough all the way :( I could re-seal them one at a time and use a clamp to hold the one in place while I remove the other but the old master cylinder I am using is putting alot of manky/dirty fluid through them so I'd kinda like to have both pistons out and clean everything before re-installation and then put them back on the car empty and clean! Anyone got any tricks on how to get both pistons out at the same time?

Posted: Thu Oct 28, 2004 10:17 am
by Nick Moss
If you have a compressor you can get the pistons out with air, but they come out with a bang so beware and keep the whole caliper covered with a thick towel. When one comes out, push it back in and clamp it to get the second one out. Make sure you clean out all the old fluid

Posted: Thu Oct 28, 2004 10:50 am
by bjmullan
Really take Nick's advice about covering the caliper well when using compressed air. I nearly lost my head one time as then do come out with a BANG :oops:

Posted: Thu Oct 28, 2004 4:48 pm
by Ian Donkin
Also worth knowing (though I suspect you'll be going down the DIY route) is that Classicar Automotive do a really great job of refurbing calipers - they come back as new (inc. re plating of the outer surfaces).

I sent them my 3.2 fronts a couple of years ago and they came back within a couple of days. They advertise in the back of PP if you are interested.

Posted: Thu Oct 28, 2004 5:54 pm
by Rose
I had mine professionally refurbished after numerous failed rebuild attempts and they came back looking great (all gold and shiny!!!) and working perfectly.

Rose

Posted: Fri Oct 29, 2004 9:08 am
by Airhead
Yeah I had thought about that but I'm trying to get the car MOT'd back on the road on a shoestring budget. Will probably get them professionally rebuilt or exchanged at a later date once I get around to making the car shiny. How much dollar are we talking anyway? I dont get Porsche Post as I'm not a member.

Unfortunately I dont have a compressor :(

Posted: Fri Oct 29, 2004 10:45 am
by hot66
I rebuilt my rears with out the use of a compressor ( i do have one, I just don't have my garage electics sorted out yet :roll: )

My pistons were stuck fast, so after leaving them with penetrating oil soaking , I managed to force the pistons out using my fancy floor mounted cycle pump :roll: :lol: Took a lot of swearing etc but I did manage to get all the pistons out. Bit of wet & dry to remove the rust build up, new seals & all was good 8)

I think the co that rebuilds the callipers charges approx £ 60 per calliper

http://www.ddk-online.com/phpBB2/viewto ... =callipers

http://www.ddk-online.com/phpBB2/viewto ... =callipers

Posted: Fri Oct 29, 2004 11:18 am
by Ian Donkin
Airhead wrote:How much dollar are we talking anyway?
Spot on James!

From their ad this month:

911 1966-73 Front 2 Piston £60.00
911 1973-89 Front £58.00
914 1969 on Front £60.00
1962-65 Rear 35mm £66.00
1966-83 Rear 38mm £58.00
914 1969 on Rear £85.00
356 Front £62.00
356 Rear £66.00

Price includes zinc / passive plating, new seals and new pistons.

If I was being really picky, from memory they do not use the same style bolts when they reassemble the two halves, but I guess this will only be of importance to concours entrants.

Their tel number is 01625 860910.

BTW - I'm nothing to do with them, they are just good at what they do.

Posted: Fri Oct 29, 2004 11:54 am
by pix912
You might check out this topic: http://www.ddk-online.com/phpBB2/viewtopic.php?t=605
Back to the the stuck caliper. On my car 4 were stuck and I've got them out without any special tools. Remove the complete caliper and put it in the freezer for one night. Next day heat up the outside of the caliper and hit it with a wooden hammer, the cylinder will fall out after a few knocks.

Piet

Posted: Mon Nov 08, 2004 12:01 pm
by Bob_Salmon
Got the first of mine striped down yesterday - alloy front from 72 2.4S - followed advice about soaking in diesel for 24 hours first, then G clamp & compressor. Took a while but once I got fractional movement on the first piston it was possible to drive it back in with the G clamp and blow it forward again. After a couple of goes it came out, and yes, it does go with a bang! Without the advice here I might well be typing this with shortened fingers.........................

Actually, it seems to be in quite good condition although after 32 years the alloy casing is never going to look perfect. So, my question :lol: Has anyone tried painting their calipers? I have seen paint (and decals!) advertised but is this a good option? Also, any advice on a suitable paint or perhaps clear protective lacquer will be appreciated.

Cheers all.

Bob

Posted: Wed Nov 10, 2004 8:57 am
by Bob_Salmon
Bump this one! :lol: And at the same time, can anyone advise on preserving the alloy hubs please? Can they be anodised again or perhaps a clear lacquer coating?

Thanks

Bob