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WOW! Eric’s site continues to be a godsend! It has given me the confidence to do many of my own repairs and in fact have posted a few of the step-by-step repairs in the other section.
Now I am on to the replacing the steering rack on my 1989 Honda Accord Lxi, 5 speed, FI, 2.0L, 250K+ miles, original owner car! That video of Eric’s is the greatest!
But today’s questions are about the front brakes! While I was doing the UCAs, TREs and Sway Bar links a buddy glanced at the brakes and said you need new pads and rotors. So NAPA was having a sale on brakes last summer so I bought the front sets. Didn’t put them on because, well I figured I get my money’s worth out of the existing brakes and as soon as I heard the signs of metal on metal scraping I could swap the rotors and pads. But now that I am into the knuckle anyway, its time to do the brakes.
So I pulled the pads and rotors off (once again Eric videos to the rescue!) and noticed uneven wear: the RF inner pad was worn down to the metal and the outer pad was rather thick.
In fact, the LF pads had more wear on them than the RF outer pad. Hmmm, I was scratching my head on that one…well, until I watched this video! https://www.ericthecarguy.com/brake-videos/511-how-to-diagnose-and-replace-a-bad-brake-caliper
Question Answered!So I watched that video twice and took notes, then watched the older video and added to the notes. Then I watched a few more brake videos and searched this forum for the last 2 months…but still I have a few questions. Hope the forum is as kind in helping out once again!
1. I see the recommendation to crimp off the brake lines using the fuel line protected vise-grips. That makes sense and looks straight forward. However, it brings up two questions (maybe I over think things?):
- A. My parts guy says that those rubber hoses rot out from the inside out, so isn’t crimping them going to aid in break down of the hoses?
- B. What does one do if they don’t crimp the hose as shown, OR, if as Eric now recommends, switches over to steel braided brake hoses that can’t be compressed?
2. I see the suggestion to NOT use never-seize on the bracket bolts, instead oil them. May I ask why? Have bolts with never-seize come loose? If keeping them in place is important, why not use loc-tite?
3. I see Eric puts never-seize on the ends of the brake pads where they contact the shims. I have seen other videos that also suggest adding some silicon paste or never seize to the back of the inner pad, where it contacts the cylinder. Is this a good idea or not?
4. New pads came with the wear indicators already installed, those pads go on the inside or out side of the rotor?So those are my questions. Appreciate any help those more knowledgeable are willing to share!
– CanDo807
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to answer some some of your questions you dont have to clamp the line… but its a good idea… basicllly why he clamps them is that it will bring the fluid back to the master syinder…. so when he takes off the claper and replaces it… he will lower the chances of getting air in the line…
when he crips it you see he is using a hose on the crimpers and he is not crimping it super hard… just berally anof to cut the fuild off.. so he doesnt damage it… Now if you see any damage on those hoses you should take it to a pro and or get them replaced ASAP… those hoses are multi layer hoses… but the first thing you will notice is the outer layer going bad first (cracking),,, so if those hoses brake you have no pressure and no pressure=no brakesto answer your question about pads un even where…. now that can be a sign of a bad claper… when you try opening it dod you feel it sezing or getting stuck… most of the time its the I dont know what you call them boot bolts… they are getting stuck and not moving smothly also can be your clips that hold your pads in… now you will see more were on the iner then the outer because of the side where the caliper is on… but should be prity close
I think that got all your pointsI call the boot bolts floating pins.
The bolts that hold the caliper to the caliper mounting bracket that allow the caliper to float back and forth after you release the brakes.
Not really a bolt most of the time but a pin that bolt goes into that had a rubber boot around it, it should just pull out.
1. I use a bleeding tool (vinyl tubing into a waste container) to divert the excess fluid while compressing the piston.
2. I believe the issue is that lubricants should not be used for a dry torque specification because the bolts can be over-torqued or break – the accuracy of a torque wrench is dependent on the friction between the fastener and hole. Or, the torque value can be adjusted to account for the lubricant if the information can be found.
3. The service manual for my car specifies to add grease between the shim and pad and where the pad contacts the caliper/piston – to reduce noise IIFC. I only use a small amount of brake grease in these areas. I would not grease these areas if the new pads have a rubber or elastomer layer instead of a shim.
4. The wear indicator on the inboard pad should be installed on the leading edge of the rotor as if the car were moving forward. The up-down orientation of the indicator can be confusing because some cars have the calipers positioned towards the front while others cars have the calipers towards the rear.
Personally, if your car is almost 30 years old and the brake hoses have never been replaced, it would be a good idea to consider replacing them anyway. Rubber doesn’t last forever and a brake failure is scary as fuck.
You don’t have to open the system to push the piston back, that’s just Eric’s preferred way of doing it. If you don’t want to, you simply push the piston back and the excess fluid goes up into the master cylinder. You could just open the bleeder and let the fluid out. I avoid opening the brake system up unless I have to, I also wouldn’t try to open a bleeder from 1989 unless I was prepared to replace the caliper. But that’s just me.
Anti-seize is a medium suspended in an oil product. Oil is just oil and will run off. Anti-seize won’t, I also find it does little but make a mess. A touch of oil is just for efficiency, if the threads are overly dirty or damaged, cleaning them is the best recourse. Anything else is just covering up an issue. There’s also the matter of dry torque versus wet torque. Unless otherwise stated most torque values are rated with dry fasteners. Any sort of medium can throw off the amount of actual torque being applied and the even application of torque. Clean threads and mating surfaces are the best way to ensure proper mounting pressure. If you want to you can use non-permanent thread locker, most cars use it at the factory.
It sued to be necessary and may still be necessary if your pads have no, or damaged anti squeal shims. It won’t hurt, but it isn’t really necessary on a decent set of brake pads.
Wear indicators go to the inside. The inside pads are usually the first to freeze up in the caliper bracket.
You don’t say whether you determined if you had a caliper failure or not. If one of the pads was seized in the caliper bracket, it will make the pair wear differently. The one pad will move in but won’t be able to release pressure. The left front pads will also wear slightly more than the right front, assuming left hand drive because most driving is done with only the driver in the car.
[quote=”Hanneman” post=170791]1. I use a bleeding tool (vinyl tubing into a waste container) to divert the excess fluid while compressing the piston.
2. I believe the issue is that lubricants should not be used for a dry torque specification because the bolts can be over-torqued or break – the accuracy of a torque wrench is dependent on the friction between the fastener and hole. Or, the torque value can be adjusted to account for the lubricant if the information can be found.
3. The service manual for my car specifies to add grease between the shim and pad and where the pad contacts the caliper/piston – to reduce noise IIFC. I only use a small amount of brake grease in these areas. I would not grease these areas if the new pads have a rubber or elastomer layer instead of a shim.
4. The wear indicator on the inboard pad should be installed on the leading edge of the rotor as if the car were moving forward. The up-down orientation of the indicator can be confusing because some cars have the calipers positioned towards the front while others cars have the calipers towards the rear.[/quote]
now with the disk quiet…. I uslly recomand ppl use the spray insteid of the gel because if you add to much you could get it on the boot of the cliper causing it to start and tear it…I have see a lot of macanics putting it all over the indide of the caliper pisten and getting it on the boot… or adding to much gel to the pads and getting it alll over the boot… and slowly cuasing the boot to tear and get dirt in the piston… but with the spry prity much inposable to over add it
I do like your idea about adding the indicator to the leading edge… never thought about it đ
Wow! Thanks to all for the replies! Iâm always pleased at the depth of knowledge gathered here!!! Each reply brought something to the table. Thanks so much!
To clarify things a bit. That video on âHow to analyze a bad brake caliperâ told me that the uneven wear on the RF pads could be a caliper issue. The sliders were OK, though on the other side (left) one of the boots had a chunk missing near the bolt head.
Replacement boots are on order. The old pins and bolts look good: a little work on the wire wheel and some rust remover (Naval jelly – loc-tite brand) should make them like new.
Also per the video I did the Piston Compression test. {Side note: Yeah, the old bleeder valve was well fused to the caliper! But nothing a liberal application of PB Blaster and a 10mm socket with a 3-ft long cheater couldnât fixâŠsomething else for the wire wheel!} So once the bleeder was open, used a C-clamp and board to compress the cylinder. The cylinder compressed readily and when I went fast the brake fluid shot out of the bleeder! So everything looks like it should, per the video!
The brake hose looks good: no signs of cracks, wear or stiffness of the rubber. In fact, the white factory printing is still visible on the rubber. Does that survive the sand blasting, grease & oil and harsh conditions in the wheel well?
I think it makes sense to clamp the line while compressing the cylinder. I sure donât need the fluid going back up into, and potentially damaging ,the master cylinder! At least not on this old car! (Did see a non-Eric video that said just take the cap off the Master Cylinder [sounds too easy]) But watching another Eric video (the brake fluid replacement?) has me thinking that perhaps the âstick compressing the brake pedalâ trick might be a work around if the hose canât be (steel braided) or shouldnât be (older than dirt) squeezed? Would that work?
But then again the advice to replace those lines that are 27 years old makes good sense: add that to the punch list! I have not seen any cracking on the hose lines, so that is good. Sure would hate to have a hose split and loose brakes! I doubt the mechanical emergency brake would do much: probably lock up the rear wheels and let the rear end skid. Will have to remember to kill the ignition and leave the clutch engaged (MT) if brake loss occurs! But replacing the lines makes more sense.
Ah good point! I learned something today! Dry torque spec versus wet torque spec! That is good info for someone who is the King of Never-Seize! So my liberal use of never-seize is probably OK for bolts holding sheet metal on, but not so good for places where there are torque specs and the specs are critical to safety and proper function. Now that has me wondering if there is a ârule of thumbâ for wet versus dry torque? +/- x%?
OK, the wear indicator on the pad goes on the caliper cyllinder side! Got it! Also it needs to go on the leading edge â that suggests to me that there is a right and left pad! Indeed after checking, yep, the wear indicators are on opposite ends of the new pads. Whew! So many important details to know about this stuff! This knowledge is what makes technicians worth their weight in gold!
So as a car is rolling forward, the right wheel is rotation clockwise. To anything bolted to the knuckle, the leading edge is going to be on the left side on the upper half of the wheel and on the right on the lower half of the wheel. Drawing this up got me recognizing the whole thing is flipped L-R on the left side!
But wait! Now I am confused! Thought that the most worn pad was on the inside (engine side of the rotor) . Isn’t that what one expects with a bad caliper!. But thinking about the old padsâŠthat means that the pad with the wear indicator was on the OUTSIDE (wheel side) of the rotor! And since this was the right side, the wear indicator was on the right side. Not what one expects if the wear indicator goes on the leading edge. So in doing diligence in my reporting, I took this picture which showed me the error of that logic!
Clearly the back side of the pads shows the the wear indicator pad was in contact with the piston of the caliper – per the round circle on the back! So 1) it was properly installed on the inside of the rotor. 2) but that means the pad that was worn down to next to nothing had to have been on the OUTSIDE of the rotor! That is NOT what I expected. I thought a locked up caliper wore down the inside pad first?. Does THIS situation indicate a different problem? Or am I confusing myself?
Wow, even something as relatively easy as brakes has many fine points! That is what is so good about Ericâs videos â he doesnât just show a repair that goes smooth, he shows when things donât go smooth and adds in lots of extra details and tips! But also great to have the kind people here with all of the knowledge! Thanks again for all of the help!
Here is a mini-treatise on brake pad wear for your enjoyment (or amusement? LOL) …
BACKGROUND INFO
The pad that comes in contact with the caliper piston is called the inboard pad.
The other pad is called the outboard pad.
New pads have approximately equal amounts of friction material on both inboard and outboard pads.
Always replace pads in complete axle sets (both inboard and outboard on both left and right wheels).EVEN PAD WEAR
This is normal, expected, and caused by proper brake function. To fix this kind of wear, replace the brake pads and hardware such as abutment and anti-rattle clips, service (lubricate) the caliper guide pins and slides.EXCESSIVE OUTBOARD PAD WEAR
This condition occurs when the outboard pad has significantly more wear (evidenced by less friction material) than the inboard pad. This is not normal and proper brake function can be affected. Wear like this is caused by the outer pad continuing to ride on the rotor after the caliper releases. Seizing guide pins, bushings and slides are usually at the root of this. Correcting this kind of wear is relatively simple. Service or replace the guide pins, bushings, or in extreme cases the entire caliper, and replace the brake pads with a new set.EXCESSIVE INBOARD PAD WEAR
This condition occurs when the inboard pad has significantly more wear (evidenced by less friction material) than the outboard pad. This is not normal and proper brake function can be affected. This kind of wear happens when the caliper piston is not returning to the rest position due to a worn seal, damage, or corrosion. It can also be caused by a problem with the master cylinder. To correct this kind of wear, take the same steps as fixing outboard pad wear, as well as inspecting the hydraulic brake system and the caliper for residual pressure and guide pin hole or piston boot damage, respectively. Any damaged or corroded parts should be replaced, up to and including the entire caliper if necessary.TAPERED PAD WEAR
The friction material is worn in either a horizontal or a vertical wedge pattern. This kind of wear is caused by improper pad installation as well as guide pin wear. One of the guide pins or slides seizing can also cause tapered wear. The procedure for correcting this kind of wear is the same as correcting outboard pad wear. (Note: tapered wear is actually normal for some vehicles, especially for small rear caliper systems. Check the factory service manual for wear information and service limits for your vehicle when this condition is observed)CRACKED, GLAZED, or LIFTED EDGES OF FRICTION MATERIAL
The friction material is physically damaged and shows signs of thermal distress. This can be caused by many things. Overuse, improper break-in or bedding-in procedure, hydraulic system problems, seized caliper components, defective pads, incorrect type of pads, and the parking brake not fully retracting are some common problems. This can be corrected by replacing and bedding/breaking-in the new pads properly. The parking brake may also need service and adjustment.OVERLAPPING FRICTION MATERIAL
The top edge of the pad overlaps the top of the rotor. This can be caused by wear on the guide pins, caliper or caliper bracket or having the wrong rotor or pad on the vehicle. To correct this kind of wear, Ensure that the vehicle is fitted with OE specification diameter rotors and replace the pads with the OE recommended type.Thanks Cap! That is some great stuff there! I have printed it out for future reference! Much appreciated!
So the plot thickens on my Accord brakes! Guess the problem was with the left side. So I pumped up the brakes as Eric did to test the brake lines… but with the caliper off the rotor, it just extended the cylinder a bunch. Then loosened the bleeder and nothing came out, so removed it and still nothing came out! The bottom of the bleeder was all gunked up as was the chase(?) to the cylinder. The cylinder looked like the one in Eric’s caliper repair video, so I clamped off the hose and pulled the caliper. I’ll repair this one, even though Eric says it isn’t worth it, just to learn how everything works and understand what is involved.
When I am done, if anyone is interested I can post pictures and what I found.
Thanks again to all for the help!
[quote=”johnnyguitar” post=171146]Do I need to change caliper bracket when changing caliper??[/quote]
Not unless it’s damaged. It’s a rare thing.
I wanted to make sure I’m on the right track. The car is 16 yrs old and want to save some money
TY friend[quote=”johnnyguitar” post=171146]Do I need to change caliper bracket when changing caliper??[/quote]
As OP said unless it is damaged or, I’ll add, unless the recesses the pins go into are damaged.
If you have a bad boot on one of those pins then water & dirt could have gotten down inside there. In that case the bore/recess needs to be cleaned and inspected. I found that while the boots were good on three pins, the “grease” still looked shot and gritty. (I expected dirty grease in the bore where the boot was damaged) So I cleaned all the bores and inspected the insides. Thankfully for me the bores were not rusted, scraped or damaged. I also cleaned and inspected the pins and they showed no signs of wear. Now when I put it back together with copious amounts of silicon past it will be like new and should operate fine.
I dunno, the way I approach things is probably a bit different from how a shop does things. Anything I can clean up while I am there, I figure I’ll do to put things in as good a shape as I can. When the customer is paying by the hours, one doesn’t have time for the over kill I do.
Still working on the caliper rebuild. Got the caliper body stripped and prepped. Noted it is a Nissin brand so likely the original caliper! Two coats of POR-15. (note that it is rated to 450 degrees F!) Now need top coat. Cylinder was a surprise as it cleaned up nicely – the only corrosion was on the ring/end that contacts the inboard pad. So I’ll reuse that. Pins, bolts and bleeder all cleaned up nicely! Now just waiting on the square seal, dust boot and pin boots to arrive. Picked up new DOT 3 fluid so nearly ready to go!
[quote=”johnnyguitar” post=171146]Do I need to change caliper bracket when changing caliper??[/quote]
No. Those rarely go bad.
OK, so thanks to all of the help here I was able to complete the front brake job! Thanks again to all who commented!
I rebuilt the left caliper, just because I wanted the experience and wanted to understand what was involved – probably won’t do that again!
Here are some pictures of the finished job!
Notes:
It took a lot longer to bleed the rebuilt caliper than I expected! Even after “gravity” drainage while I worked on the other side.
Glad I bought a gallon of brake fluid as the “stuff that came out was disgusting and I’ll need to flush the rears too.
I put a VERY minimum amount of never seize on the threads of the bleeder to avoid the nightmare of removal in the future.
Packed the cleaned (4) slider bores with silicon paste, inserting the pins pushed the excess out along flat spots on slider pins.
Small amount of never seize on the end edges of the new pads and on the backs of the pads where they contact the cylinder & carrier.
Pads came with two sizes of shims(?) for the caliper body (other shims go on carrier), I used the larger ones.Have not yet road tested, since I went directly to a steering rack repair and got stuck on that.
as long as you feel comfable rebuilding the caliper you can do that… just make sure it doesnt leak …. some ppl rebuild them and dont use new parts or dont know what they are doing and say like that boot looks ok I’ll re use it… and the boot is torn and brakes fuild goes out and they loose there brakes… I just want you to know… but if you do it correctly your good… sometime you have to re home the cylinder and you have to get some specail tools to do that but else prity easy
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