kzn185 or kzj95 Front Caliper Rebuild

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As I have got a lot of useful information from here I decided to put some notes here for anybody attempting front caliper rebuild.

Removal
1. Before removing from the vehicle, remove pads and extend the pistons till they touch the disc. Keep an eye on the fluid level in the master cylinder as one side with new pads will take the level from max to min (this is the easiest way of getting the pistons to extended, especially if they have seized. Saves a lot of farting around with compressed air or pullers).
2. Unbolt the abs sensor at the back of the hub and put out. Has an o-ring on it and may need bit of a wriggle to get out.
3. Unbolt the bracket holding the hard line from the caliper to the suspension.
4. Clamp the brake hose so master cylinder does not drain.
5. Undo the hard line into the caliper.
6. Unbolt caliper and remove.

If a piston is seized plan on having to replace it as rust has normally caused pitting in the piston.

Seals - the first lot of seals I got were from BNT, they had no listing for kzn185 but had listing for kzj95 which is the same. The second lot of seals I got from SCA. The dust seals were too small and had to be stretched to fit. The seals from SCA do not come with any brake grease so you have to buy that separately. So I when to BNT got a second set of seals and redid the dust seals.

These calipers are normally a pig to bleed if there is air on the side opposite to the bleed nipple. The answer is to minimise the air on the opposite side. Minimising the air is done on reassembly.

Reassembly
1. fit blanking plug to the inlet of the caliper.
2. Fit piston seals with a light coating of brake grease or brake fuild.
2. Lay caliper on side (clamp in vice is good) with inlet down.
3. Half fill caliper with brake fluid.
4. Fit pistons on inlet side only far enough to engage the seals (don't want to get air trapped between the walls of the caliper and the piston).
5. Flip over so the inlet is on top.
6. Remove blanking plug on inlet and cover with rag so fluid doesn't squirt you.
7. Fill cavity with brake fluid up to seals.
8. Fit pistons only far enough to engage the seals.
9. refit blanking plug.
10. Stand the caliper up with the bleed nipple up.
11. Crack bleed nipple.
12. Push bottom pistons back slowly
13. Push top pistons back slowly
14. Close bleed nipple
15. Fit dust seals

Refit, fit pads and bleed, genital tapping caliper with hammer can help move small bubbles.