[Silico]

Hi guys,

I have recently attempted to put new seals and bearings in the swivel hubs of my 03 Jimny. Reason being is the front left side was leaking diff oil so I bought a whole rebuild kit. Normally I would have just taken it to the mechanic but when I did, they only performed a basic service and told me to do the hub rebuild because "it's easy and I have a shed". I believe i'm mechanical minded enough to not bugger it up and I can follow the abundance of instructions that the Internet had given me. The kit included wheel bearings, king pin bearings, axle oil seal, wheel bearing oil seal, seals that go on the back of the knuckle and maybe 1 or 2 others I have forgotten about.

Upon completion of the rebuild I went to test the car. Turns out the brake pedal is now spongy to the point that it will slowly and vaguely stop the car when the pedal is held to the firewall and the hubs no longer lock into 4wd.

Brakes

-I have pulled the wheels and calipers back off and re-torqued to spec in case the caliper slide bolts weren't allowing it to slide correctly.
-The calipers were simply tied to the front springs while the hubs were being rebuilt so the hoses weren't undone or messed with in any way.
-I have installed new extended brake hoses AFTER discovering there was a brake problem. Since bleeding was the next thing to try I thought this would be a convenient time to fit them.
-I have bled the system approximately 5-10 times going from rear left, LSPV, front left, front right.
-I am baffled as to why my brakes would cease to function after performing work that was completely unrelated to the braking system

4WD

-I can successfully select 4H and 4L and a solid 4WD light appears on the dash when it is supposed to.
-From reading I suspected blocked vacuum lines.
-Cleaned all 4 vacuum lines (hoses and nipples) on front hubs with pipe cleaners to remove gunk.
-Cleaned vacuum lines where they attach next to the front diff.
-Cleaned vacuum lines where they attach up near the battery in the engine bay
-Hubs will engage (well they sound like they engage) when using an air compressor to blow air into the lines from both at the hose next to the diff and hoses in the engine bay.

There is the possibility of 4WD not working prior to the rebuild as it appeared one of the vacuum hoses next to the diff had been pulled off. This probably popped off a few weeks prior when testing articulation at a mates place to diagnose whether I should get extended brake hoses. I hadn't attempted to put the car in 4WD since then coincidentally.

I know this is a big wall of text but any advice would be hugely appreciated! Thanks, Matt.

[Bulldog 61]

did you bleed the master cylinder as I imagine it would have drained aft removing the brake lines

[Silico]

Haven't bled the master cylinder. I've been reading the service manual and doing some googling and no where mentions how to bleed it. Does it have a bleed nipple?

[Jezza86]

did you use a hub nut tool to remove the vacuum ring inside the air hub? if you used a chisel it can break the vaccum and the hubs wont engage.

sounds silly, but are you sure the break pads didnt fall out? sounds like a caliper piston going full travel onto the disk with no pad.

[Silico]

Yes I bought the expensive hub nut tool. Certainly made it easier. I can assure you the pads didn't fall out. I pulled the calipers back off and refit them just to make sure they were fitted correctly.

[Silico]

Rookie mistake. Turns out the caliper slide bolts were cross threaded into the caliper. New bolts and rethreading of the caliper fixed the problem. Brakes have never been better though with new fluid and braided lines. Onto fixing the vacuum hubs next.