Brake rebuild questions

[Dogma]

While I'm overhauling everything that's not electrical or a steering bearing on my front end, I'm rebuilding my brakes. I have a couple questions that don't seem to be addressed in any of the vast quantities of info around here.

1. What fluids can meld the dust boots and turn what's left into glue? The melted parts are disgustingly tacky and similar to rubber cement in consistency. The worse areas are droopy and almost dripping. Most of the damage was on the left caliper, which is also the side with the fork leak. The other side had some damage too, but not a leaky fork seal.

2. The guide pads (#7 here) seem to have been glued on at some point in the past. There was a thin film of what may have been epoxy or CA on the caliper holder (#6) where the pads go. The pads look like they should stay in place without glue, but I'm not certain they shouldn't be glued for some other reason. Should they be glued? If so, what glue should be used?

Bonus question. The no. 2 caliper axle (#10) has a plastic or rubber sleeve on it that seems to have swollen, probably by absorbing some fluid. I'm not sure I will be able to get it back into the bore. The new axle is only $7, so I'll get a new one on order. Any thoughts on causes? The same part on the caliper with much less dust boot damage seems to have no size issue.

Thanks in advance.

 

[salty_monk]

Swollen rubber parts are normally due to fluid/oil contamination. Sometime you get a cocktail of oil, brake fluid, brake dust etc in there & it seems to cause this.
No glue required on the guide pads.

Dan

 

[Guest]

q2 - if you are referring to the backing plates for the pads then you only need to use a bit of a brake caliper grease on them (inbetween the pads and the plates), certainly no epoxy

 

[hampshirehog]

The guide pads shouldn't have anything stuck to them - grease nor glue. They are a spring fit - the wee tabs on the ends keep them in place. I suspect the PO got fed up with them falling out on re-assembly and stuck them in (thay can be a mild PITA). If they fall out, just tweak the tabs.

Cheap pattern rubber parts can melt easily with any oil / fluid contamination. Go OEM if possible. (The dust boots aren't essential and can cause more problems than what they're worth by the way).

The axle should be a nice snug fit. I'd be surprised if that sleeve had swollen as a result of fluid contamination as it's not a place the fluid could reach easily. Still, if it's only $7 it's a cheap item

 

[Guest]

grease is used on those plates to prevent squaling noise that otherwise MAY occur

 

[Dogma]

Thanks, everybody. That's the stuff I needed.