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Drum brakes, all new, pulls left hard, hub still gets HOT

I see ! Just trying to help you think through ! Good luck , I personally hate these type things, one thing, I replaced my wheel studs to all right hand , drums became problematic, after that I had to be careful how I tightened lug nuts , now start at bottom and go to top so drums are positioned correctly !
 
Possible bad brake hose on LF. Hose/ fluid gets hot and will not allow fluid to freely flow back towards master after brake application. Maybe take it out, get brakes nice and hot, and jack it up as soon as you get back home and see if that wheel is much harder to spin than right. If it is , quick as you can, open bleeder and then see if it spins easier. Sometimes you can tell if you have a bad hose just by opening one front bleeder at a time, with master cylinder top off, and see if they gravity bleed themselves, and compare the flow rates from each side. Obviously an internally ruptured hose will not flow as well. Also, I adjust front drums to just complete one full tire rotation with a moderate amount of spin force, with cold brakes.
Odds of a hose being bad are slim, I'd think - the car did this with both the former front hoses on it as well as
these brand new, USA made ones. Process of elimination then?
Still, as previously posted, I DO want to do the jack it up HOT test to see if there's any clues there....

Yes, I also like more drag when cold on brakes typically. These are much "looser" right now intentionally,
as I continue to chase down this annoying issue - AND not knowing the expansion characteristics of the
rather "exotic" compound of the Porterfield friction material.
 
I can’t decide if it’s the brakes or electrical issues that draw me to these old mopars but they got me hooked for life.
 
I have had that problem both front drums I have wanted to use. The 9” I tried 3 shoes and 2 drums to finally get a set that would not rub and get hot and now my 10” on the Coronet I replaced the shoes and it’s doing the same thing. I just think parts for drums are just junk today. I put disks on the 9” and will likely do the same on the Coronet.
 
Oh sorry, didn't catch that this wasn't a new issue. Just wondering if your exotic shoes are chamfered ? As a previous person noted, we did use to have to grind/sand problem shoes sometimes to eliminate high spots. I did follow, and find interesting, your thread on accumulating all your brake parts. I run 11"X3" manual drums all the way around on a built '67 GTX, and smaller versions on a '71 Valiant.
 
I see ! Just trying to help you think through ! Good luck , I personally hate these type things, one thing, I replaced my wheel studs to all right hand , drums became problematic, after that I had to be careful how I tightened lug nuts , now start at bottom and go to top so drums are positioned correctly !
Thanks - and yeah, studs have been a lot of fun on this whole project also.
In fact, a LOT of fun:
https://www.forbbodiesonly.com/mopa...on-stock-sizes-for-wheel-studs-please.224155/
 
I'm just going to throw it out there. Hub gettting hot, could it possibly be a bad wheel bearing?
 
I have had that problem both front drums I have wanted to use. The 9” I tried 3 shoes and 2 drums to finally get a set that would not rub and get hot and now my 10” on the Coronet I replaced the shoes and it’s doing the same thing. I just think parts for drums are just junk today. I put disks on the 9” and will likely do the same on the Coronet.
Yeah, as much as I've resisted the dreaded "conversion" to discs - it's looking more appealing all the time.
My whole goal was to restore the brakes on the car as closely as possible to what they were back close
to when the car was new, including refusing to use anything "imported" on them.
So much for those austere plans.... :)
 
Oh sorry, didn't catch that this wasn't a new issue. Just wondering if your exotic shoes are chamfered ? As a previous person noted, we did use to have to grind/sand problem shoes sometimes to eliminate high spots. I did follow, and find interesting, your thread on accumulating all your brake parts. I run 11"X3" manual drums all the way around on a built '67 GTX, and smaller versions on a '71 Valiant.
Yeah, I wouldn't even know where to begin doing something like that without proper equipment...
I DID notice something last time I had both sides apart for another marathon session, however:
There's a LOT more brake dust on the drivers' side inside there, even though mileage at this point
isn't more than a couple hundred miles.
When I try to look at the shoes themselves for clues, though - they're damn near jet black and seeing
anything odd is difficult at best.
I do also know it's nothing to do with the drum, though - I have not only the two on the car now but
two spares as well and nothing changes by trying any of them on the problem corner.
 
I'm just going to throw it out there. Hub gettting hot, could it possibly be a bad wheel bearing?
Again, all of that is new. Hub, bearings, seals, all of it - and the wheel free wheels quietly and smoothly
with no slop in any direction when spun by hand.
 
Also another thought is to have a helper hit the brakes when in the air and you try each wheel and see how quickly each sides brakes release when said helper let’s off the pedal.
 
Just FYI frt drums and hubs on some older mopars were never serviced separately, only as a unit part ! Drums and bolts swaged together!
 
I might be inclined to call Porterfield and ask if even remotely possible that they
managed to send you two different pad compounds.
Dave
 
I might be inclined to call Porterfield and ask if even remotely possible that they
managed to send you two different pad compounds.
Dave
That, as odd as it sounds, is a possibility at this point.
If both sides begin at the same point, are identically equipped and adjusted - yet react quite differently
once underway - there's got to be SOME sort of difference somewhere, right?
 
Just FYI frt drums and hubs on some older mopars were never serviced separately, only as a unit part ! Drums and bolts swaged together!
They all came factory swaged - and they all come apart and can be used separately just fine
thereafter. If the drum is located flush to the hub and centered/located properly on the center section,
there's no reason for it not to be fine.
 
Before disc brakes were wide spread brake replacement procedures were done a little differently than today.
\#1 Asbestos linings were used # 2 The shoes were "ground" the match the arc of the shoe to the actual radius of the drum.
Neither thing is allowed today. Read your service manual on drum brake shoe replacement procedures.
Other wise you will not get full shoe to drum contact.
No need to switch the shoes from side to side, just swap the drums side to side. This will fix pulling and vibrations sometimes as the machined surfaces can get a directional "grain" to them. Rotors do the same thing. Always replace brake components in axle sets. Both drums, both rotors etc... this is always recommended by the brake component manufacturers.
Gert a $20. infra-red temp gun to check for heat differentials not only on each side but in different areas of the drums, hubs etc...
 
I beat my head against the wall for awhile with a similar problem, all new stuff, before figuring out the brand new drum were out of round, one side more than the other. Had them turned and fixed the pull.
 
Latest doings on this issue today (you know, since the damn website didn't work and all....):

Once I got the LF shoes disassembled and off the car, some rudimentary inspections followed -
starting with seeing if they were arched anywhere near the same as the drum:
LF leading shoe arch 9-9-21.jpg
LF trailing shoe arch 9-9-21.jpg
I realize this isn't a scientific, measured method, but they sure looked close enough for me.

Next, I tried to check both shoes to see if the frames were actually plumb (90 degrees) from friction
part to backbone part - and according to my carpenters' square, they were pretty spot on there, too.

Finally, I went to town on the friction surfaces of both shoes with a rather aggressive, open-web sandpaper
and took off most of the checking/hazing/whatever that weird wear pattern was on them:
odd wear on leading shoe LF 9-9-21.jpg
odd wear on trailing shoe LF 9-9-21.jpg

Finally, I selected the better looking of the two spare drums I have (they were both fresh machined when I
bought them a few years ago) and gave it a quick cleanup with Brakleen + light sanding to clear any rust.
It's all installed on the car and Fred is back on all fours after some rudimentary adjusting and testing with
my wife behind the wheel operating the brake pedal while I spun wheels and observed.

I also re-packed the bearings on the LF again (figured they'd gotten hot, so why not)...
I reckon another test drive is on the agenda tomorrow to see if I did any good.
If not? I'm pretty sure it'll turn out to be something in the fluid distribution components...
 
Back in the day I always had the brake shop "arch" the shoes to match the actual diameter of the drum. That has a major effect on the contact pattern of the shoe to the drum. The quality of parts now is not what it was 50 years ago. If the shoe radius doesn't match the drum radius on one side, you get exactly what you describe.
 
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