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Technical 40' Ford brakes sucks balls.

Discussion in 'Traditional Hot Rods' started by dsiddons, Oct 14, 2013.

  1. dsiddons
    Joined: Mar 6, 2006
    Posts: 1,542

    dsiddons
    Member
    from Indiana

    I'm over it. Everything is new and still suck. The drums were turned and still not round. Which makes it difficult to adjust. I've decided to go with aftermarket Lincoln self adjusting. My question is can I leave the brake system as us and bolt on and go? Leave the rear as is. They seem to be okay. No matter what I do the left grabs a bit more than the right and still they thump the pedal a bit.


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  2. alchemy
    Joined: Sep 27, 2002
    Posts: 20,516

    alchemy
    Member

    Did you try some round drums before you condemned the old brakes? I'd think properly turned drums would make a world of difference.
     
  3. dsiddons
    Joined: Mar 6, 2006
    Posts: 1,542

    dsiddons
    Member
    from Indiana

    I could I guess. What I'm seeing now is a very small area of the shoes are being used. But good idea. Buy the drums first than go from there.


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  4. What alchemy said, any drum brake sucks when the drums are junk.
     

  5. dsiddons
    Joined: Mar 6, 2006
    Posts: 1,542

    dsiddons
    Member
    from Indiana

    Also, after I turned the drums they were pretty good but seem to go out of round as they wear??? Any thoughts there?


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  6. visor
    Joined: Aug 11, 2002
    Posts: 513

    visor
    Member Emeritus
    from Missouri

    Try and find a shop that can arc the shoes to your turned drums.
    What do you mean by "self adjusting Lincoln brakes?" Are you talking about
    Bendix self energizing brakes?
     
  7. dsiddons
    Joined: Mar 6, 2006
    Posts: 1,542

    dsiddons
    Member
    from Indiana

    In the past builds I've used So Cal's Lincoln brakes and loved them. This time I went with original stuff and just down right unhappy. I will try new drums to see what happens. I don't mind adjusting them often that's part of the experience.


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  8. Sometime in the last 30 years people have forgotten some of the important things that MUST be done when doing a drum brake job.

    If you haven't had the shoes arced to the drum....you are basically pissing in the wind. Especially after having the drums turned. No amount of new drums is going to matter.
     
  9. Bruce Lancaster
    Joined: Oct 9, 2001
    Posts: 21,681

    Bruce Lancaster
    Member Emeritus

    " very small area of the shoes are being used"
    Biiiig problem, you are supposed to have 12" drums and shoes arced to a 12" circle...
    You can tell from wear pattern if arc is big or small.
    Shoe arcing has to be sought out, as the asbestos scare made it at least borderline illegal...people can still be found.
    Many folks have improvised by simple grinding/sanding ends or middle (depending on problem) of shoes and then fitting them in in use. They gotta match, you need to get at least close to 100% contact!
    Next...find and fully understand (there are online versions) the '40 type adjustment...shoes are first fitted with the use of the LOWER adjusters in conjunction with the big uppers to get everything in place. Once arcs are matched and this full adjustment is done, service adjusting is uppers only until you get a new set of shoes.
    Proper adjustment on early Ford hydraulics is AS CLOSE AS YOU CAN ACHIEVE. This can mean whispers of friction at first with new parts wearing in.
    Drums...are they really out of round? Measure. What size are they? IMHO...and I have seen this in print from an actual brake engineer to support what I have seen...turning drums for minor grooving/rivet damage can be a mistake. You can cut a large amount of mass and service life out of a drum to get rid of some grooves...and the shoes will wear right into those grooves and use them fine with a few miles. If they are grooved to hell or significantly out of round, of course, you have no choice but to turn, but you will be losing service life AND cutting out the mass that is needed to cope with heat. Ford drums that are cut much should be relegated to use on a 2,000 pound roadster, not a '40.
     
  10. dirty old man
    Joined: Feb 2, 2008
    Posts: 8,910

    dirty old man
    Member Emeritus

    Over 50 years ago I worked in an auto parts store that also had a small machine shop. Among our services was a complete service for drum brakes, both drum turning, shoe relining with rivets, and arc grinding shoes (I have the asbestosis today to vouch for my involvement). Sometimes we put shim equal in thickness to amount removed from drum under the lining before rivetting. Also available were shoes with bonded lining that was thicker than stock to help make up the difference. Usually though, these needed some arc grinding to be right.
    AFAIK, today's brake linings don't have an asbestos content to worry about, but I imagine it's a damn tough job to find a place that still has arc grinders for brake shoes.
    If you're careful to not tailgate and stay alert, you can wear them in while driving by applying brakes while driving along with no one behind you, release, continue driving to cool brakes and do it again. As you wear in the linings, you will need to readjust and will feel the brakes improve. But it's a slow and potentially dangerous process.
    Wish I could find a shop that still had a shoe grinder, but I doubt there's one anywhere near me. All the old stores that had them have either remodeled or closeed and the arc grinders are mostly gone. Let's face it, it's a disc brake world, except for us traditionalists :(.
     
  11. alchemy
    Joined: Sep 27, 2002
    Posts: 20,516

    alchemy
    Member

    If they are round to start, then get warped easily (out of round), then maybe they are too thin. A new set of drums might be the way to go. Then get those shoes arced and adjusted like everybody says.
     
  12. Have you given any consideration that it may not be the brakes but a bad brake line hose trying to collapse,,as the age what you eluded to can happen. HRP
     
  13. Model T1
    Joined: May 11, 2012
    Posts: 3,309

    Model T1
    Member

    Some really good advice here. Use it.
    I've had a 1939 Ford 4-door and 2 1939 coupes with original brakes. Plus my 39 coupe with 54 Chevy brakes. All worked very well considering no drum brakes are all that great.
    Remember, 1939 was the first year for hydraulic brakes on a Ford. 1940' a little better.
     
  14. pasadenahotrod
    Joined: Feb 13, 2007
    Posts: 11,775

    pasadenahotrod
    Member
    from Texas

    Early Ford drums should not be turned out larger than 12.060". After that they quickly become warped during a hot stop and there after useless.
    The new ones are expensive but way better than over-turned junk. The brakes are really quite good especially on a Model A which weighs considerably less than the 39-48 group.
     
  15. dsiddons
    Joined: Mar 6, 2006
    Posts: 1,542

    dsiddons
    Member
    from Indiana

    As far as the system goes its all new plumbing and such. I'm not sure I can find anyone to arch the shoes. I asked around a little before and was a deadend.


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  16. dsiddons
    Joined: Mar 6, 2006
    Posts: 1,542

    dsiddons
    Member
    from Indiana

    I do have a question. If I can't get this ironed out and go with the new stuff would they be comparable with the rear Oem brakes?


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  17. Find a heavy truck shop. They can usually do it.

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  18. I think I have found someone (I am in Los Angeles) but one time I returned the shoes to the place that relined them to have them turned.

    Charlie Stephens
     
  19. dsiddons
    Joined: Mar 6, 2006
    Posts: 1,542

    dsiddons
    Member
    from Indiana

    Thanks for the advice. I won't give up yet. Like to make these work. I'll check some heavy truck shops and go from there.


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  20. So lets see the contact patch on the shoes - whatcha got a few inches maybe ?
    So your 12" drum brakes are working at 25% if you have 4.5" total contact. Yet they still stop it, imagine if they were proper ?
    Add in the egg shaped drums and I bet they suck balls.

    Here's your short list of must have items.
    Round drums
    Fitted shoes
    Proper adjustment
    True backing plates.
    There's more but without those 4 don't even bother chasing anything else.
     
  21. Christom
    Joined: Nov 3, 2011
    Posts: 217

    Christom
    Member

    When I built the rear brakes on my AV8 I started with nothing more than the stock backing plates mounted on the '40 rear end I bought. All the old OEM stuff I found was junk so I went all new (repro) - shoes, drums, springs, cylinders, adjusters etc - even the hubs were new. I bought the drums & hubs from Speedway and everything else from C&G Ford in Calif. So nothing matched up that well when assembled. It took some getting right - especially getting the parking brake adjustment working in with the hydraulic system. A bit of persistence was required but the main point of difference was arcing the new repro shoes to the new repro drums. I adjusted them to rub and pulled the drum and hand sanded the black rub point until I got almost all the shoe being marked up by the drum rubbing. It took a bit of messing about but it really worked out well. So it can be done at home for sure. I still drove about with the handbrake lightly applied for a bit just to set the shoes to wear in after the sanding process. Readjusted as per the book and these brakes work very well - especially in my little lightweight coupe. Fortunately the OEM fronts only needed new cylinders and the short shoe relining (had been previously assembled back to front) the rest was okay as is. Those front drums do have slight grooving but are still round so were used as is. Again working very well. So grab some 40g emery cloth strip and deal to those pesky shoes and all will be fine in the end...:)
     
  22. Glenn Thoreson
    Joined: Aug 13, 2010
    Posts: 948

    Glenn Thoreson
    Member
    from SW Wyoming

    I've never had any gripes about these brakes when they're done correctly. Problem is, people no longer remember what all has to be done to make them work right, and they do work very well when everything is right.
    First --- The drums, as mentioned, should never be more than .060" oversize.
    Second --- If the drums have been turned more than .010" oversize you need shims under the brake lining or you won't be able to radius grind the lining to match the drum without losing too much lining. Shims require riveted lining.
    Third --- The lining needs to be radiused so that it makes 100% contact with the drum.
    Fourth and very important -- There are TWO adjustments on the early versions of these backing plates. The shoes must first be centered in the drum. That's a big reason why you aren't getting full contact. This is done by having someone put about 30 lbs of pressure on the brake pedal while you adjust the anchor bolts at the bottom of the backing plates. Loosen the nuts and turn the inner screw until the bottom of the shoe is firmly against the drum. Two adjustments per wheel. It takes two people to do this. No shortcuts!
    Fifth ---- After you have centered all the shoes, send your helper home and adjust the main adjusting cams. Your wrench wants to turn down to tighten. Tighten each adjustment until you get a heavy drag, then back off until the wheel is just free with no drag. A little light touching here and there is to be expected.
    Be sure to check for proper free play in the master cylinder push rod. It must not touch the piston when not in use.
    If there is no air, leaks or other problems the pedal should be near the top and hard as a rock.
    If you do all these things carefully, your brakes will stop the car really well.
    Good luck......
    --Glenn--
     
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  23. Lytles Garage
    Joined: May 6, 2011
    Posts: 621

    Lytles Garage
    Member

    The 40 brakes on my 36 panel truck stop very well,but I have the small arbor brake lathe for rear hubs and shoe arcing machine that were made for the early brakes, also the brake centering tool to adjust the shoes with the drum off, without the proper tools it would be very difficult to make them work to right !! Chris
     
  24. Tank
    Joined: Nov 8, 2002
    Posts: 749

    Tank
    Member

    The '40 brakes I have on my AV8 coupe work fantastic. I started with all OEM stuff. The backing plates i used were super nice originals, and the drums and shoes were NOS stuff that had cosmoline and 1940 newspaper stuffed into the bearings. The shoes fit the drums perfectly as they had never been turned...

    Dont forget that if you are using '39-'40 style backing plates there are 4 adjusments on every backing plate. You have to adjust the bottoms as well as the cams on the top! It takes a bit of working at, but once adjusted the do work well.

    The later "early" backing plates with the dimples around the diameter of them only have 2 adjustments. Just the cams at the top.
     
  25. I haven't the time to read all the post tonight so if someone has already addressed this I apologize.
    1) When turning the drums you must turn them mounted to the hubs not by themselves
    2) Then the shoes must be arched to each drum and installed with that drum
    3) Follow the correct adjustment procedure for lockheed brakes.
    This will ensure correct and total shoe contact and provide good braking.
     
  26. ANSWERS:

    1) The drums and hubs must be turned together. If a shop wants to take them apart go somewhere else. Find a shop with the right tools by asking at a Model A or Early V8 Club.
    2) The shoes must be arced to each drum and kept with that drum (unless the drums are the same size)
    3) Of course follow the correct procedure for adjusting

    Charlie Stephens
     
  27. hightower611
    Joined: Dec 7, 2009
    Posts: 139

    hightower611
    Member

    An old timer told me that they would, and still do, arc shoes to the drum by clamping the shoe into the drum and heat(with a torch) the frame of the shoe therefore stretch fitting the shoe into each corresponding drum. When cooled it supposedly is arced. Anybody else heard of this or any thoughts on this?
     
  28. JasonCarGuy
    Joined: Apr 16, 2008
    Posts: 131

    JasonCarGuy
    Member

    It's called matching the shoes to the drums. Never done it with heat just bent the shoes after I reclined them to best fit the drums without rocking.


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  29. jkeesey
    Joined: Oct 12, 2011
    Posts: 652

    jkeesey
    Member

    I just got my "true-arc" brake shoe grinder up and running. After practicing a few times I can see why brakes work so much better when the shoes are arched to the drums. Its an absolute perfect fit.
     
  30. pasadenahotrod
    Joined: Feb 13, 2007
    Posts: 11,775

    pasadenahotrod
    Member
    from Texas

    AH, old time technology comes to the rescue.
     

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