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I finally got that stuck anchor plate off; had to cut it with a die grinder but finally got it off and new one on, adjusted everything including the e-brake and even replaced the dust covers on the e-brake cables, so I finally really consider my brake job done now.
My question is, I have a weird noise I didn’t have before. During braking, it pulls evenly and smooth but as I get down to say 10 or 15 mph, I hear a “whoop whoop” sound. It is pretty loud, and stops if I let up on the brake pedal. I don’t hear it when slowing a little in traffic, of when just coasting down, but only the last few feet of a full stop.
Do I just need to brake hard a few times to get the new shoes “set” more or something?
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In what condition are the drums? Did you do any machining/truing/deglazing.
Good call to spin the wheel while someone BARELY applies the brakes in order to try and detect any hit and miss in the shoe to drum contact.
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"New shoes" as the saying goes? Shoes reversed? Small chamfer needed on the leading edge of the shoes? Problems with the stabiliser springs or lack of them? How do the wheels spin as the brakes are gentle applied? Drums like need to come off for a better diagnosis. I don't recognise "Whoop-whoop" as a standard indication of a problem!
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“Whoop” was the best way I could think of to describe it! Maybe I can call it a squeak, it’s definitely rotational, right as I get to the end of braking. If I brake lightly, I can almost avoid getting it.
I struggled with which shoes went where; the shoes with less lining material on them go on the front side, right?
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Sounds like you need to pull a drum or 2.
Take and post pictures of the brakes with the drums removed and maybe we can see what's wrong.
Leading/front shoe has the shorter friction material.
--
Eric
Hi Performance Automotive Service (formerly OVO or Old Volvos Only)
Torrance, CA 90502
hiperformanceautoservice.com or oldvolvosonly.com
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Drove it to/from work today, and it seemed much better today, but not totally gone.
I’m pretty certain I got the shorter shies to the fronts, BUT the thing I noticed was, I couldn’t see any visible “camphor” (if that the right term) like I see in the pics in the shop manual - the edge of the lining material seemed just squared off.
I’m tempted to try to drive it a little but more to see if it improves before I start pulling hubs again(?)
Someone else brought up the drums themselves - fair point, I just hit them with some brake cleaner and wiped them down, focused on the getting the new shoes in place. The old shoes were really gone, but to the car’s credit it wasn’t making any weird brake noises at all before my brake job.
It was taking a while to slow down tho.
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I know just enough to be dangerous, but the one thing I remember from being a teenager and working on drum brakes is to take the shoes and drums to a machine shop and have them "arced" to the drums. My mechanic did a thorough inspection on my newly acquired PV several years ago. He noticed, among other things, new shoes were installed, but after road testing the car, they didn't act like they should. He pulled the drums and arced the shoes accordingly, never a problem since then.
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Interesting point. Doing some research on this led to many posts about this subject, and some hints on how to do it with some basic supplies. It does seem to be getting better over time but I still get a sharp screech right as I stop rolling, about half the time. I think just normal braking is gradually kind of “arching” them to the drums, but maybe I could speed up the process. For whatever reason just the very final bit of stopping sometimes produces the sound, but some stops I don’t get it at all any more, and the tone has changed from the intense noise I was hearing initially as I slowed to the final little squeak just as I completely stop moving now, for what it’s worth.
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Grinding the shoes to match the drums is laid out in the PV Green books. It was common practice back then. Running it rather mis matched shoes may generate a lot of brake dust. This may be causing the final squeak. Best to have a look if you haven't already. You'll at least be able to see any high spots that have been produced. A tickle of those with a nice sharp file will help you get a better percentage of material in contact with the drums. Check after 500 miles?
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Good idea to recheck and then see if I can spot any high spots. I will do that.
I’ve already done a couple hundred miles since replacing them, so getting close.
I guess I just never “got the memo” on turning drums and arching shoes!
Only other car I owned with shoes was an Austin Healey and I guess I just lucked out, plus it had disks in front so my odds for drum issues was cut in half! Everything else has been disks until my PV.
Looking online I saw lots of comments on how hard it is to find shops that have the tools or will do that work anymore - sounds like kind of a lost art.
Anyway now I have lots of masks and can do some careful filing on any high spots.
Thanks for the help!
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Just look for a brake specialist with grey hair........
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Issue seems to be solved.
I finally got time to dig into this again. My son was able to tell that the noise was definitely coming from the front brakes, and only during the very last few feet of braking. It was happening on just about every stop, but got worse the hotter the brakes would get.
Pulled front hubs and using a file, l put a more pronounced angle on the leading shoe lining.
Basically held file vertical and worked back and forth along edge of material. There was a slight angle there to begin with but I filed until I had maybe a 1/4 inch wide band across the shoes that angled down through maybe half the thickness of the lining. Also did same to edge of the “back” shoes.
I cleaned the drums and also added a little more brake grease on the contact areas on all shoes.
I also noted one side the springs sort of “interlaced” and crossed over each other on the pin, so I re-set those springs on to the pin so one was cleanly on top of the other. Not sure if that could have been a factor but it didn’t seem right how I had done it initially.
Reinstalled hubs and wheels and then adjusted all 4 brakes. Also adjusted hand brake cable.
Wow, what a big difference! Stops are nice and crisp with zero squeaking. Pedal is firm and less effort required.
Thanks to everyone who offered all of your help and advice!
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I know just enough to be dangerous, but the one thing I remember from being a teenager and working on drum brakes is to take the shoes and drums to a machine shop and have them "arced" to the drums. My mechanic did a thorough inspection on my newly acquired PV several years ago. He noticed, among other things, new shoes were installed, but didn't act the way they should. Pulled the drums and arced the shoes accordingly, never a problem since then.
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