Installing 39/42 brakes on 34 Diff. need Help

[MAG]

New cylinders installed. Drums turned. Brake shoes re-lined, arced to drums and centered on backing plates. Adjusted out far enough to allow installing drum. Problem is I can not install the E-brake pull lever because the croll link appears to be too long. What am I doing wrong?

[Jason in TX]

Not sure what you mean about the croll link...

I had to put some of the spring up into the tube, and then put the spring clip on half of the spring. this shortened the cable sticking through the backing plate, and connected the E brake link. This was done on a Model A rear end.

[MAG]

Not sure what you mean about the croll link...
Typo....should be cross link.
So far the pull cable has not been a problem. I can not position the pull link in front of the rear brake shoe where it belongs. If I do, the cross link pushes the shoes out too far to allow installing the drum.
The link measures 5 3/4 center to center in length. Acording to the Green Bible these links are the same part 39 through 48.
I have checked the shoes against a 46-48 shoe and they are the same.
These parts were brought to me in a box so I was not able to see how they should be installed. Don't know what I am doing wrong. Any help appreciated.

[Jason in TX]

Here is a parts drawing. I'll see if I can find more pictures...

[Jason in TX]

Here is a set up... Looks the same as what you have. Why can't you pull the lever forward anymore?

[Jason in TX]

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it looks like both shoes are long shoes on your wheel. The front should be the long shoe and the rear should be the short shoe.... Not sure if this would change much of anything, but perhaps because you are using both front shoes on one wheel might have something to do with it.

[MAG]

Yes, the parts all look to be the same. One thing I can not determine between the two is the length of the cross link. Mine is 5 3/4 inches long Center to Center. I.e. measured on a vertical line from the mounting pin to where the link connects with the stud on the pull arm. If my cross link was about 1/2 in shorter I think all would be well. I can pull the Pull Arm into place in front of the shoe. Doing so pushes the front shoe forward blocking installation of the drum. Thanks Jason for your help.

[MAG]

Originally Posted by Jason in TX

it looks like both shoes are long shoes on your wheel. The front should be the long shoe and the rear should be the short shoe.... Not sure if this would change much of anything, but perhaps because you are using both front shoes on one wheel might have something to do with it.

All 4 shoes we lined with full linings. No short (front) linings were done. Incidently they were re-lined by a professional brake and clutch shop here in Austin doing business for over 40 years. I agree; I don't think it will cause a problem other than a little harder brake pedal.

[Jason in TX]

You may need to arc your shoes. Are you using new cast iron drums? You may also need to just turn the drums a little bit. I assume you have the brake cams turn inward as to not push the shoes outward.

[APDAVE]

If I am seeing correctly looks like the wheel cyl. is on backwards too ! but that wouldnt hold the shoes out. Dave

[MAG]

Using used original cast iron drums turned by brake shop. Shoes arced and matched to the drums by the brake shop. Yes, all adjustment cams turnned inward. Everything points to the cross link being too long. I don't have a known original 39/42 to measure.

[bobH]

richard (ev8g) has covered this many times... give him a call 626-338-2282

[MAG]

Dave, looking at Jason's exploded view of the brake system it appears that the big end of the cylinder is oriented toward the front of the car on both front and rear brakes. I read on the HAMB that they should be installed that way. But....
And the boxes they came in were marked Right and Left. If they were reversed the hydraulic lines would have to enter from the front of the axlle housing. The hydraulic lines that came with the car have them entering from the rear side of the axle housing.

[Mart]

I think you have let the shoes push the cylinders in too far. Without being able to lay my hands on them it's hard to tell. Just pull the lever into the correct position and see if the drum will go on. Be very careful, because a lot of cylinders currently made have the feed hole drilled into the bore too far up the bore. The fluid will leak past the seal if the piston gets pushed back too far.

I have had a correspondence with Mac's on the subject.

Mart.

[MAG]

Originally Posted by Mart

I think you have let the shoes push the cylinders in too far. Just pull the lever into the correct position and see if the drum will go on.
Mart.

A comparison with my shoe position in the cylinder and that of Jasons they appear to be the same.
If I pull the lever into position it will push the front shoe forward blocking installation of the drum. When the shoe goes forward it will allow the pistons in the cylinder to expand due to internal spring pressure.
Thanks for your thoughts, Mart

[MAG]

bobH, I called Richard and sent him a picture. He is looking at it. He measured a cross link and it is the same as mine.
thanks, Paul

[hardtimes]

Originally Posted by MAG

bobH, I called Richard and sent him a picture. He is looking at it. He measured a cross link and it is the same as mine.
thanks, Paul

Hey MAG,
Hm, I doing the '39/'42 brake job now on my '36. I will have a puller in a day or two to pull the rear drums. If I have that act done and you have not solved your problem, I'll get in touch with you and see if I can help with my setup.
BTW- I'm NOT a brake specialist..for sure! So, take this comment with a 'grain of salt',eh Ford designed/made brakes for decades...with the primary/secondary linings of differing lengths. On early (lockheed/anchors ...what you are working with)setups, one shoe/lining gets 'energized' more than the other (which one energized, depends upon whether veh is going forward/backward). When mostly going forward and pushing applying brakes....LARGER shoe gets 'pulled into drum , ergo energized' while whereas non energized shoe has to be forced out into drum via piston. IMO this was designed to have more uniform wear of linings and to make use of mechanical advantage available (mostly front shoe) with this setup. Because Ford engineered brakes this way, I wonder if both shoes of equal size...would/will cause unintended/unwanted results! Mabe not
Any brake engineers available for opinion

[MAG]

Hardtimes, Because Ford engineered brakes this way, I wonder if both shoes of equal size...would/will cause unintended/unwanted results!
For sure I am no brake specialist. What I have learned abour these specific brakes has taken place in the last week or so. As far as the "long" lining on the front shoe goes, I think it might take more foot presure to operate the brakes but I have no data to support that idea.
Yes, I would appreciate any pictures you may have when you get the hub pulled. Right now I'm stumped!

[richard crow]

jason in the picture it looks like you have the anchor pins not set right . both flats schould be faceing eatch other after the drum is on you then adj them

[DICK SPADARO]

All parts are assembled correctly, Check for a wear burr on the cross link groove that is preventing the operating pin of the Ebrake rocker to fully seat at the base of the cross link guide groove.. If the rocker pin does not seat the rocker will kick outward. You can make a backyard brake gauge out of heavy card board by cutting out a 2" deep x 12" wide internal U shape and using it as a checking gauge similar to a caliper. To insure that the lower cams are adjusted correctly there are dots on the rectangular tangs of the lower bolts. To start the dots should be aligned to 12o'clock position on both lower bolts. To adjust, the dot on the tang is rotated away from high noon, front bolt to front , rear bolt turning rearward.

Size of the shoes make no difference, if anything it gives you a little more brake surface for you that tail gate.

[APDAVE]

Mag Take a look at Jasons assy drawings. Dave

[Jason in TX]

Originally Posted by richard crow

jason in the picture it looks like you have the anchor pins not set right . both flats schould be faceing eatch other after the drum is on you then adj them

None of these pictures are of my car. I'm at work in an office and I did a quick search of the internet to find photos of 39 brakes.

My brakes at home work fine.

[hardtimes]

Originally Posted by MAG

Hardtimes, Because Ford engineered brakes this way, I wonder if both shoes of equal size...would/will cause unintended/unwanted results!
For sure I am no brake specialist. What I have learned abour these specific brakes has taken place in the last week or so. As far as the "long" lining on the front shoe goes, I think it might take more foot presure to operate the brakes but I have no data to support that idea.
Yes, I would appreciate any pictures you may have when you get the hub pulled. Right now I'm stumped!

Hey MAG,
For sure...WE are both on a learning journey! So far, these guys have figured out (from pics) what the heck is going on with my brakes! THE FRONTS..ON BACKWARD
Ok, I just got in mail rear wheel puller from Ariz (God bless you son)! Just pulled right rear and will show pics of what was found....and I don't think that anything found was GOOD Posting pics on my '36 thread in minutes. Please view them there and let me know what you think/see.

[MAG]

Score another point for Richard early V8. Following his suggestion to measure the length in the slot of the Cross Link, the problem was discovered. He stated that he has seen the ends of the Cross Link slots welded up to counteract wear in linings, etc. The correct length of the slot is 7/8" measured from the top/long tip of the slot to the rounded end. The two on the car measured 3/4". The welder was an excellent craftsman as there was no welding evidence. I would never have looked there were it not for his suggestion. Weld removed and all fits well.
Thanks to all who responded to my plea.
MAG

[Jason in TX]

Thanks for posting your discovery! Great learning tip there! I'm glad you got it figured out!