It's time for some brake work

[zbane]

Hello everyone.

I've got a question regarding brake calipers, and the rebuilding of them.

My FRONT brakes have been squeeking for a little bit, so I know it's time for new pads. I pulled the wheels off the other day, and found that the calipers are sticking/stuck. They relax after a while, but harden up after driving, to the point of smoking (the smoking started today). I've searched the threads and gleaned much useful information, namely that it is indeed time to replace the hoses (cracked originals), and to use the appropriate flared wrenches. Also to keep fingers away from calipers when expelling them with pressurized air, if doing a rebuild.

My question (finally) is this-are caliper rebuild kits from BlackDragon (or MSA, etc.) worthwhile, do they work, and are they safe in the longrun?

A shop I just went to, hoping for emergency service (parts need to be ordered, don't ya know), winced and advised against the kit. Of course they also quoted me ~$300 for the front end brake job (new hoses, calipers, pads, and labor).

Anyway, any suggestions about kits and their overall effectiveness would be greatly appreciated, as well as a basic rundown of how to flush the brake lines, if possible.

Thanks all, I really do appreciate it!

[240ZMan]

I just rebuilt my 240SX rear calipers from the JY before installing them and it was no big deal at all. BUT, if the reason your caliper is stuck is because the piston is rusted, then you may need to replace it. Mine were clean so I had no issues with that. I bought the kits from Rock Auto I think as it's not easy to find rebuild kits at the chain stores any more.

As for flushing your brake lines, the process of removing the calipers and then later bleeding the brakes is going to flush all the old brake fluid out of the lines. But if you are looking to do something more aggressive, like run something through them to clean them, then I'll let others who have done that respond.

[zbane]

I peeked under the rubber boots, and it was all clear, at least what I could see. The passenger side boot has a small hole in it, and was the more stubborn of the two to manipulate (push back in), and now it's the one that has started smoking, so who knows about that one...

At the price of the kit, I see no reason to try the rebuild first, and should one (or both) be in less than perfect condition, I'll get the new caliper units, I just didn't know if they were worth their salt, so to speak.

[JimmyZ]

They winced because they wanted to sell you their service. Nothing wrong with caliper kits. What's wrong are how some people rebuild them. Sometimes people think they can get away with a scuffed or notched piston. This is one possible reason why caliper rebuild kits are becoming more difficult to obtain for many makes models. (Not just Nissan)

I rebuilt mine a couple of times before getting new ones. I would assume that my calipers were rebuilt three to four times. All the rebuild is is an inspection , cleaning and replacement of rubber parts. Use chrome polish to clean up the pistons. The Ra (Surface finish) of a sliding seal surface is important) If one absolutely needed to polish a rough spot the 400 followed by 600 would do. This would give you a limited lifespan on the piston since it would now be prone to rust now that the plating is gone. Scrap the caliper if the piston is too far gone of course. Since our calipers don't have sliding bushings there is no need to measure anything else. Before you start trying to undo brake lines get a can of parts blaster or some other fastener unsticking stuff. Spray it on all brake line ends and let it set for an hour or two. Even a decent brake line wrench can strip things if the fasteners are rusted. Vice grips are the last resort but what a mess.

Take your empty calipers to someone to be glass bead blast the bores for rust removal if you can. Some of the older caliper kits come with small O-rings for the caliper halves. Don't take the caliper halves apart unless you have these rings. It is better to not take the halves apart anyway. Simply following the instructions in your Haynes manual will get you through it.

Hope this helps.

[Arne]

Check prices for exchange calipers that are already rebuilt. I bought a pair for my '71 from Schucks (Kragen) for all of $29 per side. No pads, but all rebuilt with new pad hardware and a lifetime warranty. Not worth getting all messy inside the caliper for that price.

[ktm]

What Arne said. You can also find remans on Ebay for around $70 shipped.

[zbane]

Thank you all for your replies-I'll take a peek at Napa and Advance, see what they've got for rebuilds. If reasonable, I'll go that route, otherwise, I'll do it myself.

JimmyZ, thanks for the suggestion regarding spraying the PB stuff, I wouldn't have thought of that.

I'll pick some up when I get the wrench.

Thanks again all, I'll post back when finished, and I'll try for some photos as well.

I'm back

Napa has these:

Brake Caliper w/ Hardware - Left Front (Semi-Loaded) - Remfd

SDC

2426549 $37.99

Core $27.50

Brake Caliper w/ Hardware - Right Front (Semi-Loaded) - Remfd

SDC

2426548 $37.99

Core $27.50

Of course, I'll have to wait for delivery, but that's ok.

Thanks again, everyone.

[zbane]

Well, I have brakes that work correctly, once again.

I had intended to rebuild my calipers, but the weather was working against me. After raining all night long, I took advantage of a semi clearing day, minimal drizzle, and just a touch of snow. Luckily, the snow didn't start until I was on the 2nd wheel (passenger), and even then it didn't snow much. Replacing the brake lines wasn't too hard, especially since I had heeded the advice about getting flare wrenches and PB spray lube.

I had never bled brakes before, for that matter, I'd never messed with any brake component to any real extent before last week, so I took everything slow, and reread the FSM several times.

My drive is gravel, and it's tilted. I was worried about jacking up, so I improvised. I took the hydrolic jack from my Montero and used it in conjunction with the Nissan jack. I have a "dead" computer, and I used a side panel as a solid foundation. I would jack one up, then the other. I blocked both rear wheels with some rather large rocks, and went to work.

After installing the new lines, and bleeding them, I hopped in the car, only to find that I had no brakes whatsoever. I called the mechanic shop that I use for major work and they told me that I had to bleed all four brakes. :stupid:

Live and learn, I guess. Anyway, I still have a little bleeding left to do, though I'm going to get some help for this round of bleeding. My skateboard assistant did a great job at first, but as the pressure built up, it wasn't able to stay locked on my seat.

The brake lines were original equipment, marked 3/79 on the hose, with a copper ring marked 4/79. If anyone wants them for any reason, pm me. I wouldn't reinstall them, since they are no good, but perhaps a collecter of all things Z might want them for reference or some such.

The last photo is rather irritating. It's a hole on the drivers floorpan, just another thing to fix when it get to those frame rails...

[240ZMan]

David, glad you've made progress, and it sounds like you're close; the skate board is creative but not a substitute for a human leg.

Perhaps it's just the color in the picture, but the color of the disc doesn't look right. I can't tell if that's from overheating, or corrosion, or perhaps something else, but "it no look right".

Also, I didn't see any jack stands. Forgive me if I sound like a parent (which I am), but that's just not safe, even with 2 jacks. Any time you are going to put any part of your body under a car, there needs to be a jack stand. Don't let yourself get in the habit of making excuses, even if it's only for a minute. Jack stands are cheap, and a lot cheaper than the visit to an emergency room or worse. Sorry for the lecture, glad to see you jumping in on something new, and please be safe.

[zbane]

Daniel, you're absolutely right about the jack stands, it's on the list with a nice floor jack. The passenger side disk had some surface rust on it, I think that's the one you are commenting on, and the color doesn't look right because I was using my cell phone camera, not the best quality.

[mlc240z]

ditto on the stands. never trust a jack alone.

another thing i did when reassembling was to put a lick of antiseize compound on the line where it passes thru the nuts. did both ends of the hard lines since that's where they usually rust together making it hard to loosen. hopefully won't need PBlaster next time i need to disassemble.

also used loctite on the threads, not so much for the locking but to inhibit the threads from rusting.

had to replace too many old rusty lines trying to remove and i don't trust the availability of these parts in the future.

[BRE-240Z]

Another thing that's good to do is to put the wheels under the car. I do it even when I've got the car up on jack stands....that way, if things go south in a hurry, at least i won't be crushed under the car.

I've had a car slip off the jack, a minute or so after I came out from under the car, and that is scary stuff....

PB Blaster is good stuff, by the way. I keep it around at all times now. Not sure how often you get over to Asheville, but the South Asheville Wal-Mart sells it in their automotive department.