Can't get front brake shoes to go in so drum will fit on 48 DeSoto.

[MarcDeSoto]

I've read the manual and watched the filmstrips, but can't get the front brake shoes to go in far enough to put the brake drums on.  I've turned the anchor bolts and the cams in back, and the shoes do move in, but not far enough.  Does anyone know what I should do now?  

[vintage6t]

Maybe crack the bleeders to see if the springs will retract them a bit more.

[MarcDeSoto]

The lines have no fluid in them as they are brand new.  

 

[9 foot box]

   In another thread from Wednesday, you show a new and old brake parts. You have to use a shorter push rod coming out of the cylinders. Someone on an old post even cut the notches deeper.

[Plymouthy Adams]

I thought you were using the M19 tool for this setup, how in the world did you miss this alignment prior to trying to place the drum in position...?

[joecoozie]

Are the shoes new?

If so, the lining may be a little too thick and not allow the drums to slide on.

I have had this happen to me several times and I just had a very, very small amount of the lining skimmed off and the drums went on - no problem.

You may even try to skim off some of the lining yourself. I have done it using emery cloth working evenly along the shoe.

 

[MarcDeSoto]

5 hours ago, Plymouthy Adams said:

I thought you were using the M19 tool for this setup, how in the world did you miss this alignment prior to trying to place the drum in position...?

I don't think you understand what my problem is.  What good is the tool if you can't even get the tool to go over the shoes after the drum has been miked. Yes it could be the new brake linings are too thick, and/or the push rod from China is too long.  I bought these linings in the 80s.  I don't think so, but I wonder if they are asbestos?  

Edited February 19, 2022 by MarcDeSoto

[9 foot box]

   I have no experience with an Ammco or Miller apparatus, but I thought that you measure the drum with the micrometer on toe and the shoes it should be turned over to heel. A previous picture showed toe almost up on the shoe measurement. Is it supposed to be turned on each measurement for proper clearance?

Edited February 19, 2022 by 9 foot box

[Dodgeb4ya]

You need to check the arc fit of the shoes to each drum...shoes off of the car. Arc those shoes of they don't perfectly fit/match the drum surface.

Then also...here we go again....more Hell to throw at me.....look up the factory shoe lining thickness in the DeSoto Shop Manual.

Make sure your shoes are no thicker than the factory spec 5/....."

Then use the shorter push rods...if required.

Then start all over setting up the shoes with the MT-19.

Edited February 19, 2022 by Dodgeb4ya

[MarcDeSoto]

I checked the arc fit to the drums and they fit fine, I think.  The shop manual says the linings should be 13/64" thick, or 5.159 millimeters.  I'll check them tomorrow.  Do brake shops

still arc shoes to drums?  I may have to have the shoes arced just to get the drums back on, or get shorter push rods.  I'm trying to find my old push rods rather than use the new ones. 

1 hour ago, 9 foot box said:

   I have no knowledge of an Ammco or Miller apparatus, but I thought that you measure the drum with the micrometer on toe and the shoes it should be turned over to heel. A previous picture showed toe almost up on the shoe measurement. Is it supposed to be turned on each measurement for proper clearance?

 

You measure the drum with the micrometer, then you transfer that measurement over to the brake gauge set on Drum.  The gauge also has Toe and Heel settings.  The manual says to set the gauge on Heel and adjust the heel and toe of the shoes.  Oddly, it doesn't mention switching the gauge over the toe.  

Edited February 19, 2022 by MarcDeSoto

[Wes Flippen]

I had the same problem when I replaced my brake shoes. Sanded `em down on the bench sander. Probably not the proper way to do it, but it worked. Just make sure you only do a little at a time and do it evenly.

Wes

[desoto1939]

mARC ACCORDING TO MY THERMOID BRAKE CATALOG THE THINKNESS OF THE BRAKE LINING, JUST THE LINING IS 3/16. dURING OUR PHONE CONVERSATION i WARNED YOU ABOUT THE PUSH RODS ON THE NEWER WHELL CYLINDERS THAT PEOPLE HAVE BEEN FINDINGOUT THAT THEY ARE TO LONG AND TO REUSE YOUR ORIGINAL PUSH PINS.

 

IF THE LINING IS TOO THICK THEN YOU WILL HAVE TO HAVE SOME OF IT GROUND DOWN,   

 

RICH HARTUNG

DESOTO1939@AOL.COM

[MarcDeSoto]

I'm hoping I can find my other old push rods because the new push rods look different and might be a tad longer.  If I can't find the other old push rods, I wonder if I can grind the new ones down a tad on my grinder?  Just another reminder to keep your old parts because the new ones are sub standard in many cases.  

 

 

Edited February 19, 2022 by MarcDeSoto

[kencombs]

Sure, grinding them down is common reported fix.  As long as you have one old one to measure, just make the new ones match it.

[Sam Buchanan]

Looks like the new one doesn't have the recess for the boot to fit into.

Edited February 20, 2022 by Sam Buchanan

[harmony]

2 hours ago, Sam Buchanan said:

Looks like the new one doesn't have the recess for the boot to fit into.

I just put new wheel cylinders on my 48 Chrysler and the push rods that came with the front cylinders are the same as the shinny ones in his hand.  They are a tighter fit when going on to the boot but they do go on and do the job.  They seem to measure the same distance visually from the end that seats against the piston to the notch that rests up against the shoe, as the originals that I took off the car.  

Edited February 20, 2022 by harmony

[harmony]

Thanks for this post MarcDeSoto.  It's good info to file away, and I'm curious to see how you make out in the end.  The only thing I didn't replace when I just did my brake job was the MC and the shoes.  I just feel I can get at least another year out of my shoes.  I'd say I have about an eighth of an inch of lining left.  If I was to slack the adjusters right off I'd have oodles of clearance when sliding my drums on. 

Interestingly when I was ordering the rear wheel cylinders a few weeks after I received the front wheel cylinders that came with push rods.  I was told that the rear wheel cylinders didn't come with push rods. No real explanation as to why.  So I used my originals on the rear

I'm about to order a new set of shoes just to be prepared, so when the time comes, and they don't fit, I'll be reminded of this thread.  

[MarcDeSoto]

I just put new wheel cylinders all around on my 48.  Luckily I still had the old cylinders with the old push rods for the rear axle.  I have only found two of the old push rods for the front brakes.  I'd like to find the two others, but I might have to use the new ones.  My shoes are riveted and I think they are already arced to the drums, but I bought these shoes in the 80s and I don't remember.  They may be the original shoes that I had relined with riveted linings.  Harmony, your pic of your push rods look different from mine.  I assume the bottom one is old and the top one is new?  I wonder if I decide to grind my push rods, should I grind the beveled side or the domed side?  

[harmony]

6 hours ago, MarcDeSoto said:

I just put new wheel cylinders all around on my 48.  Luckily I still had the old cylinders with the old push rods for the rear axle.  I have only found two of the old push rods for the front brakes.  I'd like to find the two others, but I might have to use the new ones.  My shoes are riveted and I think they are already arced to the drums, but I bought these shoes in the 80s and I don't remember.  They may be the original shoes that I had relined with riveted linings.  Harmony, your pic of your push rods look different from mine.  I assume the bottom one is old and the top one is new?  I wonder if I decide to grind my push rods, should I grind the beveled side or the domed side?  

Have you guesstimated how much you need to remove?  I think it might be easier working on the notched end with a square file.  Yes, you're right my original is the pitted one on the bottom.  I kept the old ones and filled the corroded areas with JB weld and they look much better now.  It's interesting that your original ones have a notched area for the boot to sit in.  Where as my originals don't have that, just a smaller diameter.  Push come to shove, I will gladly mail you a couple pushrods if it becomes a concern.

[desoto1939]

Marc:  I would reset up the MT19 Brake gage tool and use the tool to remic the distance of the inner measurement of the drum for each brake drum.

 

Just use the drum setting on the triangular tool. The put the tool back on the specific axle. Use the drum setting to check to see if you have any high spots or area on each front or rear brake lining.  The movement of the tool with the drum indicator will tell you if there is a high spot onthe shoe lining. So start at the top of the ling and then arc down to the bottom of the lining. Do that with both shoes..

 

Also to arc the shoes you would have had to have the drums off the car and the brake specialist would have then used the AAMCO brake micrometer, not the AMMCO 1750 brake tool, to determine how big the drum is so say 11.10 or 10 thousand over. They then setup the Ammco safearc tool to your setting and then  sweep the individual ining against the sanding drum to take the high spot off each set of lining to match each drum.

 

The process needs to be done for each individual drum and you can not assume that the same distance is the same for each brake drum.  If you had this done then you would have had to perfrom this shoe grinding.

 

Rich Hartung

desoto1939@aol.com

[MarcDeSoto]

Thanks Rich.  I got your phone message also.  It's been so long ago that i don't remember if I had the shoes arced.  I think I took my shoes to a brake shop and had them put new linings on.  My linings are all 11 1/2" long and my drums are 11" diameter.  I don't remember if I took my drums in so they could arc the shoes.  It's been too long, like almost 40 years!!!  I will do what you said though.  I'm planning on taking my drums and shoes in to Bear Alignment and Brake, if they still do that kind of work.  They're closed on weekends, so I have to wait till Monday.  If it's really important, I will take my rear shoes in also so they can install short 9" linings on the rear shoes of the rear axle.  I will mark my drums as to location too for RF, LF, RR, and LR.  

[desoto1939]

the brake lining should be just a little short of the entire lenth of the metal shoe if it is a full lining and the ends should be cut on an angle and not a blunt end to the shoe material.

 

So if they arc the shoes form each drum make sure you also have them mark which drum they were cut to fit specifically.   

example Left rear:  then the corresponding shoes should be marker LR and the same with each drum this way you will know which shoe goes with which drum and the drum should also be marked.

 

Rich HArtung

[MarcDeSoto]

I checked my brake shoes by taking them off of the backing plate and putting them into the drum.  At least by eye, it looks like they have been arced because the curve of the shoe fits the drum exactly.  So I'm leaning in the direction that I did have them arced to the drums.  but I don't know if I have the right shoes with the right drum.  I know that the rear axle drums belong there because they are different from front axle drums because of the wheel bearings and the the key notch.  So now I'm thinking maybe to concentrate on finding my original push rods and/or grinding down my new push rods.  

[Sam Buchanan]

text deleted

Edited February 21, 2022 by Sam Buchanan

[James_Douglas]

One thing to note for anyone who has or finds or has someone to arc shoes...

 

There was a running change in the Ammco brake shoe machines. Some of them had the clearance built into the machine so if the drum was say 11.040 you just set the machine to 11.040 and arced the shoes. Some of the machines you had to do the math to set the dial caliper as the clearance was not built in so you would need to set it to 11.040 PLUS the clearance.

 

I have received shoes that did not fit because someone was using a machine and not following the proper setting procedure.

 

*********************************
ADDENDA TO INSTRUCTIONS FOR MODELS 850 AND 8000 BRAKE SHOE GRINDERS. 1. The recommended .030” cam grind mentioned in point 3 on page 3A has now been built into the micrometer setting of your brake shoe grinder. Therefore, dis-regard the example “A” on page 3A. 2. Set the micrometer dial (3-Figure 2) to the diameter of the drum in which the shoes are to be used. Doing this will automatically give you the correct cam grind.

********************************

In the event anyone needs it I have attached the manual for my Safe Arc machine.

 

Also, not in the manual that for the Chrysler Type arcing you need to use the fixed anchor head. 90% of the shops either do not have that head or do not know were it is. They they default to the Bendix head and the show geometry does not come out correctly. Lucky for me I have both heads.

 

James

 

 

 

Model_8000_Safe_Arc.pdf