Another Rear Drum Dragging Thread

Thanks for the info. Can you document with pictures your removal of the retainer valve. I feel like this really could be something. Myself and 2 mechanics have worked on bleeding the rear brakes in the past. I never felt like they bleed properly compared to any other car I have owned. This could be the source of our other issues. Thanks.

Will do Z. I have the previous 2 MC's, one Cordone I bought and the aftermarket MC that was on the car when I bought it. Going to learn how remove on those before I drain the fluid and pull mine on car.

Glad to hear your test drive is successful so far! I removed all my parking brake components, & tested it...no help in my case.
 
I'm not entirely sure that it can be reversed but I'll look closely tonight. I will pull a few components out tonight to see if I can determine where it is binding. It's the same for both sides so e-brake makes the most sense.

Can little changes like direction or order of springs on anchor make a difference?

View attachment 302198 View attachment 302199 View attachment 302200

Your set up looks good with one last comment.

The self adjuster screw...
when you pull up on the self adjuster cable, does it slowly turn the screw outwards? (it should)
Check both sides.
 
Well I believe I have solved my problem. I re-cut the drum on the problem side and adjusted rear brakes up to where they should be. 20 mile test drive and both drums are cool. Good brake pedal.
 
Your set up looks good with one last comment.

The self adjuster screw...
when you pull up on the self adjuster cable, does it slowly turn the screw outwards? (it should)
Check both sides.

The self adjuster was working well, adjusted when I pulled on the cable.

I disassembled the problem side tonight, sanded and cleaned the contact points, swapped the cylinder and left the e brake bar out for now. It doesn’t sit well and seems to bind.

The shoes seem to slide without binding so I not sure if there will be any improvement.

It’s hot as hell tonight so I didn’t have the energy to put the wheels back on and test. Maybe tomorrow or Thursday.
 
Back to square one for me. I did a longer ride this morning. I got the vibration again and now have an additional wrinkle. Front right disc was 350° back right 145° , left front 225, left rear 110.

I was a a fairly rough road driving 60 when I took my first reading. The rest of the roads to my destination where fairly smooth and now I was in town driving 35 in stop in go traffic. Got to my stop all other temperatures were OK but rear still 145.

Now I drove the whole way home, same city driving but a smooth road and no stops until nearly home. No vibration but rear still 145 and front discs cooler than when I stopped in town around 145 and left rear 105.

One observation rough roads definitely play into worsing the problem. The front disc heat is aggravating because I didn't think I had an issue there anymore.
 
I just remembered something, when I did the front disc conversion one of the bolts holding the caliper fell out and the car came to a violent stop.

When this occurred my master leaked brake fluid into the floor of my car. This was a one time occurrence and haven't lost any fluid since. Could I have partially damaged seal from this which is causing the master to engage especially over rough roads???
 
I just remembered something, when I did the front disc conversion one of the bolts holding the caliper fell out and the car came to a violent stop.
When this occurred my master leaked brake fluid into the floor of my car. This was a one time occurrence and haven't lost any fluid since. Could I have partially damaged seal from this which is causing the master to engage especially over rough roads???

That's not outside the realm of possibility, and I wouldn't throw that theory out the window either but I'm not a brake expert! If you've always had this issue since the swap, I would either look at your master like you say, or maybe the calipers aren't fully retracting when you release the brakes causing a slight drag issue even though there 's a natural drag with discs? Your rears don't seem to be that hot, but I don't know what a normal temp should be for that? I just hate brakes and doin the job!! Good Luck
 
I apologize for the delay all. Been traveling again for my job and working on my brother’s 67’ Polara.

As for my brake problem: I removed the residual pressure “check” valve for the rear brakes (front reservoir), kicked back the pads on the drums, went on my usual 10 mile at 50 mph test ride to see if they get hot and both were cold. I was so freaking happy. Drove back home same distance…HOT!

Unreal…I am officially out of solutions. As you saw from my previous posts, I have done everything accept change the backing plate some things 3x overs. How can both plates be bad? Plus my buddy built up one side with weld and ground it straight & flat, so we ruled backing plates out.

So the only place I know for discs is that "Ram Man" guy. He claims to have the only ones around now. Wasn’t crazy about his reviews, but another buddy just received his from him for a Super Bee and was happy. Called two weeks ago, spoke with his wife (nice), told her the deal, sent her pictures as she requested (even sent the windowed drum video)…she said that they will look over pics and call back…no call back for two weeks.

I saw the post about the Jeep Liberty discs…. I’ll have to look into it. 2 questions:

1. Anyone know if you can keep the original 14” rims with the Liberty disc set up?
2. Anyone have success with their current brake problems? Just seems like all of us are having issues with the latest "new aftermarket" brake drums parts.
 
(even sent the windowed drum video)

Oh boy! I missed that one, went on a backup hunt of the post to find that and came across this (did anybody else see this?).

Primary Return Spring is wrong.
SPRING.IS.WRONG.jpg


SPRING.IS.WRONG.FSM.jpg
 
Oh boy! I missed that one, went on a backup hunt of the post to find that and came across this (did anybody else see this?).

Primary Return Spring is wrong.
View attachment 306909

View attachment 306910

Good eyes. My springs were all the same length, so I have mine set up the same way too.

It could be the issue, but my left side doesn't get hot and it is set up the same way. I know the shoe bases are universal so there are holes which aren't used. I am curious if later models used all the same length springs or if this is the problem.

I need to check my "don't throw away factory orginal items" bin. I might just have those shorter springs in there.
 
Good eyes. My springs were all the same length, so I have mine set up the same way too.

It could be the issue, but my left side doesn't get hot and it is set up the same way. I know the shoe bases are universal so there are holes which aren't used. I am curious if later models used all the same length springs or if this is the problem.

I need to check my "don't throw away factory orginal items" bin. I might just have those shorter springs in there.

If I remember correctly, when we bought new brake shoes, there was an optional "brake hardware kit" that contained all new hardware for drum brakes, and I think it included new springs. Most of the time, we didn't bother with the kit (because we had no money) and we used the old original hardware. Maybe such kits are still available ?
 
68PK21...you are the MAN!!!! You've got to be kidding me! That makes sense!!!! The only 11x2 hardware kit on Rock Auto is Raybestos and shows that both primary and secondary springs are the same length which is what I bought!!!! (see pic)! So when we are all buying the hardware replacement kits, we're getting hung up as it pulling up and not in! I saw my shoes do that in the drum windows!

H7105-1__ra_p.jpg


Looked up part number in my 67' parts catalog and it's still the same part number for both springs. There is no unique Primary vs Secondary part number, yet in the service manual in your picture, it looks like a different type of spring and much shorter...at least shorter where it hooks to the post. Here are the orig Mopar spring part numbers:
Cross Section Color.png
Part Number.jpg


I will try to hook it to the upper hole...any thoughts on this guys?
 
yet in the service manual in your picture,

Umm it's not my picture, it's Zymurgy's picture from post #118. and I hope the FSM picture is of the correct year & car. I kind of stayed away from this thread as I'm not really quite sure what car and year we have here. I see a 300 emblem in Zymurgy's avatar and going to his profile I see reference to a Chrysler 300 emblem, but I'm a Plymouth guy, but know that brakes are pretty much the same for the body platforms and years but I really don't have a clue on the year via the Chrysler emblems I see.
Hope that's the correct FSM picture for whatever year and car he has.

Also remember from service manuals, to service bulletins to parts manuals & superseded part numbers, updates and so. This old stuff can be fun if all the parts have been mumble jumbled over the years by many hands.
 
Just to clarify the above SM reference photo in post 131, is from a 1966 Chrysler manual.

I am going to look but I am certain my from drum brakes had the short spring retaining the primary. I know I still have them from my disc brake conversion.

The manual shows the short spring retaining the primary on all 4 corners.

I am still going to order the brake kit for some of the other items supplied.
 
I can well remember from my drum brake experience from a teenager too well into adulthood that one spring is way more of a ***** to put on. You learn from experience whether you use the special brake spring pliers, vicegrips, channel locks, that when you pick up that spring you let's say put it on with some authority!
 
Here's from the 1968 Plymouth Factory Service Manual.

1968.Plymouth.FSM.Front.Brakes.jpg


1968.Plymouth.FSM.Rear.Brakes.jpg


I kept thinking leading & trailing all through this thread and someone else brought it up but I never saw any real good dead on pics of the setup like above till the other day.
FSM terms are Primary & Secondary.

I thought the cut out drum pic was hilarious, (but I kept my mouth shut)

I still don't know what year car this is, now a reference to 66 (close?)

:confused:
 
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