Wankenstein

1998 Civic EX, A/T, 180k miles. Rear drum non-ABS brakes.

My son and I diagnosed a faulty right rear wheel hub assembly over a month ago on his car. Made audible noise during driving and when we inspected it with car raised. Today we replaced it with a used hub that I pulled from my '95 EX coupe. When I pulled the left rear hub off my '95 a few months ago (pulled both rear hubs) it came off easily, inner race intact, was not making noise (driver side hub was), no wobble or free play. So, I assumed it was still in good shape and figured was okay to use on my son's '98.

During installation the inner hub bound up a bit even though we lubed the axle and hub inner diameter with synthetic grease, As we shimmied it off the inner race pulled away from the bearings. We were able to push the inner race to the backing plate and then slide the hub/bearings over the inner race. I figure it would be fine to continue to use because the washer and axles nut will hold the inner race/hub together in correct position. We tested the hub assembly by hand after installing the axle nut and there no free sided to side play and it spun freely. However when we took it for a test drive it was scraping and noisy.

We put it back on jacks, removed drum and noticed the caliper was leaking brake fluid and one side of the wheel cylinder pistons was pulled halfway out. I don't have any experience repairing/replacing rear drum brakes so I wasn't sure what happened? I purchased a new hub assembly and caliper. We installed them following service manual and videos and it went smoothly. Bled brake lines/cylinder on both rear sides. We left it on jack stands and the only thing left is to correctly adjust (star wheel) brake shoes tension. Any thoughts or guesses why the first (used) hub we installed didn't work? Why wheel cylinder piston was stuck halfway open?

My son will adjust star wheel (shoe tension ) tomorrow and test drive again. I told him to keep it jacked up, wheel on and have his friend press/depress brake while he spends tire by hand. I told him to listen for scraping, look for brake fluid (possible leaks).

ezone

Late. Tired. Thoughts.

The bearing/hub isn't making scrape noises until you put the drum on. (remove drum, spin bare hub, it's quiet---right?) The noise is brakes.

The only way the bearing/hub could be the cause is if it isn't exactly the same as the original and it's allowing the drum to sit in the wrong place (scraping the brake backing plate). More likely it's a rust blister in the groove of the drum making contact with a lip on the backing plate, or a bent backing plate.
Look for the shiny spot.

And it sounds like someone pumped the pedal while the drum was off, and overextended the wheel cylinder until a piston popped out.



Now if you removed a bunch of brake parts just to replace the hub/bearing unit and didn't get the brake parts reassembled correctly, that's on you.

Wankenstein

Thanks for the reply

Correct.

Not sure if this matters: brake shoes have good depth but some areas of uneven wear and gouging. We didn't replace though because he is (hopefully) taking the car out of town today and we didn't have time to replace shoes on both rear axles.

Used hub was from 5th gen..we installed it on a 6th gen. Everything I read said they are the same hub. Eye test..both look the same. Possibly over-tightened the axle nut during first install?

I will be at work all day/eveing today so I will forward this to my son so he knows what to look/listen for.

I don't recall doing that but, it's possible. I wouldn't have known otherwise not to do that anyway due to lack of experience with drum brakes. After new (second) hub and wheel cylinder install we did bleed it with the drum off but, pistons still intact.

Again, due to my lack of experience..the old wheel cylinder is probably still good and all I needed to do was to remove it and push it back into place. However, as stated..we did replace with a new one.

I hope it is. It looks like it is. Seems to be working correctly other than star wheel needs to be adjusted so the shoes are pushed out for more friction. I've been wanting to learn how perform rear drum brake work and was forced to yesterday. I have a much better understanding of them now. My son was a big help and he did most of the labor during both the hub assembly and rear brake disassembly/assembly.

Wankenstein

Today my son said he tensioned the shoes and noise is gone but, said there is a very slight pull to right. Not sure if this is due to over-tensioning (per video allow one full rotation of tire after tensioning via star wheel) or new wheel cylinder + component cleaning has made the side we worked on more efficient than other side and is braking quicker? I told him that after use this may balance out.

I forgot to mention that during initial drum removal it was hard to remove. We used one bolt in both slots (alternating) a bit at a time. We had to do it this way all the way to the end of the stud threads. Side note: the tire on this axle developed cupping quickly. i'm now thinking that this rim may have been over-tightened at some point and/or hit a curb which may have been the source of the noise in the first place.. but, just a guess.

What I've learned from this is to inspect drum and drum fitment thoroughly first. Drum brake shoe and wheel cylinder is not as complicated as it seems. Remind myself to always start with simplest, inexpensive items first and proceed from that point.

ezone

I didn't check hub numbers last night but I see now one of the numbers was used from 1985 to 2000. I was thinking ANY disturbance of the drum can cause rust contact, even getting drums switched side to side can bring out weird issues.
I've had instances where a noise only occurs during a hard turn too.......side loading during turns causes flex and slight movements, that's sometimes enough movement to bring out 'noises of insufficient clearance'.


Hard to remove drum may have been due to rust lip formed around the edge of the friction area where the shoes don't make contact.

If I don't have to back off adjustment to remove a drum, then I reinstall the drum as it was and I'm done. ....because the adjustment was already properly set by the self adjuster mechanism.



You do NOT want drum brakes to drag (much).
If there is too much drag, heat and expansion can cause the brake to drag even more, causing even more heat.....you get the idea.



Manual adjustment is typically to run the adjuster wheel up (tighten) until the wheel is locked (this seats and centers the shoes against the drum), then back it off just until the wheel is freed enough to rotate (maybe 5-8 teeth in general, it varies)
After that, the self adjuster mechanism should be able to maintain its designed adjustment as the system is used and as the shoes wear. (designed adjustment might not end the same as manual adjustment)

Also can be done with the drum off as long as there is not a rust lip on the edge, crank adjuster up some and see if the drum goes right on (excess shoe clearance) or if it's gonna be a tight fit (too little shoe clearance)....keep adjusting JUST until the drum will slip on with minimal drag.

Pull only during braking COULD be due to trapped air that didn't get bled, or it could be due to uneven adjustment, among several other possibilities.

Wankenstein

My son said he knocked quite a bit of rust off drum from outer and inner lip. Afterwards the rotational noise was gone and hasn't returned.

Okay

Son told me he felt one full tire rotation seemed like too much tension so he backed it off a bit more. I showed him this thread and how you recommend tensioning the shoes.

He was on the brake pedal while I manipulated the bleeder screws (ledt and right rear cylinders). I told him not to push pedal to floor..just 3/4 way. Bled out until new fluid seen, no air and then several more pumps/bleed after that.