Leaking Brakes

[chris1983rangie]

hi,

Besides my steering problem, ive also had problems with my brakes.
bleeding them is a piece of cake but after we bled them and got the landy off the stands prior to a test drive, i notice a drop of fluid on the garage floor. hmmmm....! not good.

so i jacked the beast up on stands took the wheels and drums off to find fluid droplet under the piston rubber boot same for all sides. What could be causing this? they are new wheel cylinders.

the only thing that could come to my mind that the seals are dodgy and i could be using the incorrect brake fluid. i used pbr super dot 3 brake fluid. it says yellow dot, suits Toyota's......Hmmmm......! yellow dot i thinks is higher operating temp.

im going to change fluid type and replace all seals with pbr brand. the surfaces inside the wheel cylinders are smooth and quite shiny.
is the surface better shiny or slightly roughed up?

also just a note i pulled my original cylinders out of the shed these units are the ones i pulled of the landy when i was stripping it down. i noticed the seals on these when i pulled them apart just to compare the old seals to the new one's, there was a difference. the new ones look different could they be the incorrect type?

what Brake Fluid do you all use?

cheers,

Chris.

[JDNSW]

Either DOT3 or DOT4 fluid will work perfectly with the Series 1.

Leakage from all wheel cylinders suggests that the seals are either faulty or incorrect. When you say they look different, in what way? There could be differences that don't matter.

Most hydraulic cylinders have a slightly matte finish, but a polished surface should seal. If the seals are not sealing, and there is no damage to the cylinder bores, the seals must be damaged or are the wrong size, or are not making sufficient pressure against the cylinder walls; this could be because they are the wrong seals, or because they have been stored for too long and have deteriorated, losing their "spring".

It is possible the edge of the seal may have been damaged in assembly if this was done without using rubber grease, and it is possible that the seals may have been damaged by contamination of the fluid - not much contamination is needed. Rubber brake components can be damaged just by handling with slightly oily hands, and it is possible that some contamination has found its way into the system, possibly from penetrating oil used to free up unions. If this is suspected, flush the whole system with metho.

John

[chris1983rangie]

Thanks John,

also just to note, i bought these Wheel cylinders from Ebay UK, who knows where they were made and what the quality of the seals are obviously faulty.

anyways i did order a new set front and rear in the PBR brand. hopefully this should sort my problem out.

the part no's below if anyone needs em.

Front's

RH P5021
LH P5022

Rear's

RH P5029
LH P5030

cheers,

Chris

[chris1983rangie]

ok heres some pics of my orig pbr cylinder on the left and the ebay one on the right. Chris






this is the front cylinder these didnt leak much at all just a couple of drops.
but im still changing the lot over anyways.....!

[JDNSW]

It may be a problem with the photo, but the new rubber seals do not look as if they have a sharp edge up against the cylinder wall. If this is really the case, it is undoubtedly why they leak, but I am mystified as to why they would be like that - I have never seen it.

John

[Grockle]

I think it's a quality issue Chris,as you said where are they from,better buying localy of a known brand,especialy brake items.

[chris1983rangie]

hi John & Grockle,

yea sorry the pics arent that good but yes that top edge of that seal has a 45 degree chamfer, one of the guys told me at the brake clutch co that its a double seal designed to stop air from getting back into the cylinder as well as stopping fluid from getting out.

I still think where it is made and the type of rubber quality manufactured is important too. anyone can copy a design but if you compromise the quality of material used than this is where problems begin...........so much for ISO standards and Quality Control. Its a real pitty things arent made in Australia anymore........!

oh well i got my new set today from PBR and they are ready to fit tomorrow so i let you all know how i go...!

"Stick With the Brands mate"

cheers Chris

[chris1983rangie]

hi all,

ok i installed my new cylinders on the rear axle & re fit brake shoes, springs and drums.

i adjusted the shoes with that adjusting nut on the backing plate, then fit the road wheels i can turn the wheels by hand fowards but it locks going backwards.

does any one know why it does this? maybe i got the leading and trailing shoes wrong way around. is that possible?

also just to note i have a series 2a rear axle assembly fitted.

any suggestons would be appreciated.

thanks,

Chris

[JDNSW]

Both shoes are the same, although the cylinder end of the lining on the trailing shoe must be chamfered, and the leading one you can get away without this, so it is possible that only one is chamfered and you have them swapped. The only other possiblity I can see is that the pull-off spring at the bottom is broken, stretched or incorrectly assembled, although I don't see how you could do this.

John

[chris1983rangie]

hi John,

there is no chamfer on any ends of the lining even on the end of the trailing & leading shoes nearest the wheel cylinder. how many degrees do i chamfer?

Chris.