Has anyone on here rebuilt 2nd Gen twin pot calipers?

I've got a set that I'm in the process of rebuilding, and I've run into the first problem.

As I try to install the piston seal into the bore, it seems that it's too big for the bore.

Has anyone else run into this problem? How did you solve it?

Just wondering whether you have the Verada twinpots and the kit is for the ralliart ?
Don't know if they have the same size pistons but I'm sure the calipers are different to accommodate the larger diameter rotor on the ralliart.

Edit: Looks like the piston sizes are the same ( 2x 42.9 mm ).
Are you seating the seals properly in the grooves in the caliper bores ?

I've tried as hard as I can, and there's no way on earth that these seals will fit into the bore grooves. The seal itself is about 50mm in diameter...

The funny thing is, every other seal in the kit fits perfectly...

I'd be taking them back to the supplier - sounds like the kit wasn't put together properly.
( by their supplier, not by you ).

Has anyone on here rebuilt 2nd Gen twin pot calipers?

I've got a set that I'm in the process of rebuilding, and I've run into the first problem.

As I try to install the piston seal into the bore, it seems that it's too big for the bore.

Has anyone else run into this problem? How did you solve it?

I rebuilt a pair of AWD twin pots not long ago. Basically the Same caliper but the bracket is different.

Question: Have you compared the old seal with the new seal? Are they the same size?

If they are the same size then you just need to persevere. Make sure you get plenty of brake fluid on the piston seal and only use soft plastic tools that won't damage the seal of bore. It might look too big but before you know it, it'll just spring into place.

When you put the piston back in, it has to be perfectly aligned or it wont go in. Once you get it started, you can use a brake piston tool that smoothly drives it back into the bore.

Get plenty of the special orange grease on the underside of the dust boots and make sure you get everything correctly sealed to keep the dust and crap out. And don't forget the retainer spring for the boot.

Save some grease for the caliper sliding bolts as you do not want a sticky caliper.

Good luck. It's quite rewarding when you finish.

It fits, it is just a tight fit, by design.

You wait till you get the dust boots in and their circlip to hold them.... now thats a nightmare!

It won't fit, and there's no chance of it ever fitting.

I've done some searching around, and I spoke to a rather helpful bloke at a local brake shop, who figured out that the kit I was given is for an AWD wagon.

Apparently, Mitsubishi has declared 2nd Gen ABS brakes obselete, and they don't stock rebuild kits anymore, so the salesman gave me a kit that he thought would work.

The brake guy told me that AWD wagons and sedans had different sized brake pistons, with the wagon having the larger piston, which is why the seal won't fit my sedan calipers. The sedan piston is 42.9mm in diameter, while the wagon's is about 46mm. The dust boots and bracket boots fit perfectly, but that's it.

So, a note to anyone intending on rebuilding 2nd Gen twins - either get an AWD sedan kit, or don't pull them apart in the first place... lol