Retaining bolt for brake pads on '82 XJ750 Maxim

Does anyone know the size allen wrench needed for the retaining bolt that holds in the front brake pads? The books I have show it as a pin, with a clip at the end. The both '82 XJ750's I have use a allen bolt instead. I was using a metric allen wrench, but it looked like it was going to strip out the inside, so I stopped and started treating with PB Blaster. The pads are in great shape, but I need to get them off to replace the caliper seals.

Thanks for any help.

 

It's a no 6 and you need to take your time and possibly use some heat I have 2 calipers that I unscrewed about half way before they get stuck and cannot move and have to use a thin punch and hammer to bang it out from the other end

 

Thanks, Turbo. I'll set this aside for next weekend or a free night next week so I don't rush it. I can also keep applying some PB Blaster while I wait.

 

The threaded portion is short, but make sure that it is completely unthreaded before you start tapping on it with a punch and hammer. Lubricating the whole length helps break up the corrosion so it will come out easier. Just be sure to degrease the entire caliper afterwards.

 

I'll be using anti-seize before I put them back together. I am quickly becoming a fan of it.

 

Only apply it to the threads. The rest of the retaining pin is meant to be dry.
I really like using a medium-strength threadlocker on most fasteners, and reserving the anti-seize for fasteners that get too hot for the threadlocking compound.
The threadlock does dual-duty. In addition to keeping the fasterners from backing off, it fills the airspace between the threads and prevents corrosion from being able to form.

 

Thanks for the clarification on using antisieze. I have blue threadlocker, which I think equates to medium. I've been hesitant to use it.

 

What brand?

 

Loctite. I also the red Loctite.

 

Blue is the medium strength. Reserve the red for high-torque/ critical applications where you do not want the fastener to come loose without applying heat to it (like 400ºF).

 

Will do. Thanks.

 

Those pins are a BEAST to get out. Many times, even after a day-soak in Kroil, etc,, we have to put a 2-foot "cheater bar" (a 1/2" ID black pipe) on the allen key to get enough torque to break them free.

 

Doesn't heating them help the process?

 

Not always............those puppies are IN there.

 

Guess I will continue to spray with PB Blaster for a few days, then heat it up for any help at all, then crank on it. I'm not looking forward to this. Oh well.

 

Assuming that you're rebuilding the caliper, and not just replacing pads, give the whole caliper a soak in a 50/50 mix of ATF and acetone. That is the best penetrating oil there is.

 

That I can do. I was hoping to get the seals replaced without taking off the brake lines, but I would rather do that then fight it all week.

 

i wrecked mine getting them out i was looking for replacement ones with bolt heads rather then allen screws i couldnt find any though the only place i could find replacements was the in the uk on ebay at like 20 bucks each or so

 

I was able to get the retaining bolt out of each side,keeping the brake line connected. I thought the hard part was over and the job would soon be done. It took off the brake shoes and used the line pressure to get the first piston out. The other side (right) went out about half way, so I polished the piston on the left, put the lubricant on the seals and set them in place (after a solid cleaning up of the channels), lubricated the piston with the enclosed lubricant, and put it back together. I figured I could then work on getting the right piston out. However, I am not getting any pressure to the brakes, even after bleeding the brakes. Any thoughts?

 

My first thought is that you really should be taking the pistons all the way out and replacing the seals.

My second thought is that you really should be replacing the brake lines if you haven't already done so.

My third thought is that you got air into the system when the left piston was partway out.

Yo'll be bleeding the system anyway. Remove the banjo bolts and pop the piston out with air. If that doesn't do th ejob then find a bolt to close off the brake line hole, and put a grease gun onto the open bleeder fitting. Pump it ull of grease and she'll pop out.

 

Brake lines were recently replaced with steel braided brake lines. Seals weren't done at the time as I hadn't planned to do so, but you (K-moe) highly recommended it, so I ordered them - yep, I do listen at times - grin. I also picked up the ATF and acetone, by the way. Left side piston has been completely removed, seals removed, channels cleaned, piston polished with fine steel wool, and everything put back together. I don't have more crush washers on hand, so I really want to avoid taking off the line if possible.

After reading some other threads, it seems like your idea of air in the line is most likely. I will double check to see if there is still air in the line, use a sander, without sandpaper, to help, and go from there. It's supposed to rain for the next two days, and my folks are in town, so I don't need to rush.

Thanks for the advice. I will take it step by step.

 

If the crush washers are still the original copper ones, you just have to anneal them and they can be reused. Heat them to cherry-red, then immediately dunk them in water.

 

Awesome. I have one of the original ones, as well as the new ones from the new lines.

 

Just a quick report on the final status. I picked up a brake line bleeder tool from Harbor Freight and worked on the lines. They were full of air. Once I got the air out, the other piston came right out using the master cylinder. However, I have three of the old copper crush washers from the old brake lines that I will anneal and set aside for the future. I also have a quart of AFT and a quart of acetone for future stuck bolts, which I know are just waiting for me. I cleaned up both pistons in the brake calipers, replaced the set of seals in each, bled the brakes, and thoroughly tested the braking system. Everything works great. It will be a lot easier the next time I need to work on any part of the brake system. I really appreciate the help from all of you here, and the quality parts from Len (XJ4Ever).

 

i just hooked my calipers up to the master cylinder individualy with a short antidive brake line to get pistons out

 

Cheater

 

One more thought,for anyone who is on the fence about maintaining the calipers by replacing the seals. The brakes never had an issue, even before I replaced the brake lines. However, I always found it hard to push or walk the bike, but figured it was due to the weight (first bike, only riding 10 months now). Both pistons were pretty gummed up when I took them out. The bike rolls much smoother now that the calipers are done. My theory is that they were not fully releasing. If correct, I should get a couple extra miles to the gallon.

 

hold off on the water part, just let them cool slowly. A water quench will make them harder

 

Not with copper.
Only ferrous metals harden by quenching.
Non-ferrous metals work-harden.

 

what i'm reading now is the red hot part is the important step, quench or not quenched. didn't know that.
the most important thing is only new ones are shiney

 

I'll be ordering new ones in multiple packs. However, I would like to keep the old ones for those times when I find myself without one.