Wood wheel puller works great

[GaryBudd]

I went to local machine shop and had one made.They used the hub cap for thread size.I used it today and removed both fronts  and one rear.One rear (left rear) is being difficult but we will get it.Now that I have them off is there a manual that comes close to what a 1929 DeSoto brake system? I know there is not a maintenance manual for my car.I have enclosed photos of wheel puller.

[keiser31]

If they are similar to my 1931 DB brakes, these may help a little....

[seando]

I have a 29 Desoto K and just went through the whole brake system. The above guide by Kaiser31 looks pretty spot on with the minor adjusters and major adjusters.  If you can, I would recommend you try and save the wheel cylinders and rebuild if possible. I bought all new and they are a step cylinder, one side being bored smaller than the other. All 4 of my wheels snap to a good stop but when I have the wheels off I do see that only one side of the shoe is actually moving. I have also rebuilt my trans brake with a replacement part from oldmopar (fka Andy Bernbaum) and it is tight as new. 

 

I havent been on here in a while nor have I put time into my 29 until recently. I have successfully rebuilt my vacuum fuel pump, and the clum light switch. I am trying to make videos and post of my progress in case they can help anyone.

 

I am a certified hack but am learning. 

[Spinneyhill]

Why is only one shoe contacting the drum? Which shoe is it, front (leading) or rear (trailing)? The larger end of the cylinder should be on the leading shoe.

[retiredmechanic74]

2 hours ago, Spinneyhill said:

Why is only one shoe contacting the drum? Which shoe is it, front (leading) or rear (trailing)? The larger end of the cylinder should be on the leading shoe.

The shoes are known as a primary and a secondary the primary goes on the rear of the backing plate and the secondary on the front. The larger boor in the cylinder points to the rear of the backing plate to accommodate the primary shoe. The reason behind this is...70% of driving is in forward motion...30% for backing up, but the same holds true in reverse only the shoes roll down and the secondary has the job of stopping the car . When you apply the brakes in forward motion the shoes tend to roll upward so most of the pressure is applied to the rear ( primary) shoe.and being that a much greater speed is obtained in forward motion that shoe has to push hard against the drum (the reason for the larger boor) the front shoe acts like a buffer for the drum but does help in stopping the car. On most replacement shoes you will notice that one shoe (the secondary) has less lining on it and the (primary) has about an inch more.   

Edited February 7, 2018 by retiredmechanic74 (see edit history)

[seando]

That makes sense to me. Wish I talked to you between 2nd and 3rd rebuild.  

[ArticiferTom]

I like what your saying  retiredmechanic74, but the Dodge illustration says opposite . It has the shorter shoe on rear of face plate . But does not say if it is primary or secondary . I do believe in 33  changes where made to step bore ,but do not know if shoe arrangement changed .

[retiredmechanic74]

48 minutes ago, ArticiferTom said:

I like what your saying  retiredmechanic74, but the Dodge illustration says opposite . It has the shorter shoe on rear of face plate . But does not say if it is primary or secondary . I do believe in 33  changes where made to step bore ,but do not know if shoe arrangement changed .

Through out all the years I've been repairing cars numerous times I have found incorrect information from the manufacturers. Having the short shoe in the rear will lead to premature brake wear. Although possibility back in those years that may of been the way of thinking. I began my mechanic years in 1956 when I was 13 years old working for a car lot for five years and pretty much had to figure things out on my own. But what I said in the above mentioned paragraph is proven true.   

[ArticiferTom]

Not saying your theory is wrong , actually think it is right . But the illustration for '31 is using straight piston not the step one's . So if you are using step type you would have to but longer shoe to back ,not like illustration .

   I had theses same quandaries when doing my brakes on a '31 . I opted to have sleeved straight . One other thing I would be interested in your option on . The fact they bonded my lining on, verses riveting as original .  and by doing so ran the pad both to the long length , so I have no real short side . I,ve read where the step gave better performance and was a natural improvement . But found the original works fine on my small light truck with it's max 40mph speed . It is great having first hand knowledge brought to the forum , Thank you for it !

[retiredmechanic74]

2 hours ago, ArticiferTom said:

Not saying your theory is wrong , actually think it is right . But the illustration for '31 is using straight piston not the step one's . So if you are using step type you would have to but longer shoe to back ,not like illustration .

   I had theses same quandaries when doing my brakes on a '31 . I opted to have sleeved straight . One other thing I would be interested in your option on . The fact they bonded my lining on, verses riveting as original .  and by doing so ran the pad both to the long length , so I have no real short side . I,ve read where the step gave better performance and was a natural improvement . But found the original works fine on my small light truck with it's max 40mph speed . It is great having first hand knowledge brought to the forum , Thank you for it !

I've used both style of shoes and I believe the short shoe was a cost saving move but because of that that shoe had to be up front. I like the rivet style better because all to often I've seen the bonding come loose do to excessive heat from people riding the brake pedal and emergency brake sticking. 

[Spinneyhill]

7 hours ago, retiredmechanic74 said:

The larger boor in the cylinder points to the rear of the backing plate

Interesting.

 

My 1939 Studebaker Commander and President Shop manual shows the larger end of the wheel cylinder with the longer shoe.

 

To quote p.102 last paragraph:

"The wheel cylinder is of the step-bore construction and it must be remembered that the large bore always is assembled toward the front of the car."

 

When the vehicle goes forward, the cylinder end of the leading shoe (i.e. on the front) tends to be pulled towards the drum by the drum rotation, increasing the braking effect. By putting the larger bore to the front, on this shoe, further enhances the braking energy.

[retiredmechanic74]

8 hours ago, Spinneyhill said:

Interesting.

 

My 1939 Studebaker Commander and President Shop manual shows the larger end of the wheel cylinder with the longer shoe.

 

To quote p.102 last paragraph:

"The wheel cylinder is of the step-bore construction and it must be remembered that the large bore always is assembled toward the front of the car."

 

When the vehicle goes forward, the cylinder end of the leading shoe (i.e. on the front) tends to be pulled towards the drum by the drum rotation, increasing the braking effect. By putting the larger bore to the front, on this shoe, further enhances the braking energy.

As I stated before, That could have been the thinking of that time. There have been a number of systems that were used...Two cyl's in each wheel..Step boor cyl's ...Cam eccentrics for adjustments. But in the end the car companies all settled on a single cyl. primary and secondary shoe set up and now disc brakes. Who knows what they will come up with next. But if your comfortable with those book instructions then I would say follow them.    

[Bill Harmatuk]

Large shoe to the front.

1/8 inch larger diameter boor, (bore), to the front.

Riveted brake shoes.

AAAANNNNDDDDD (And), silicone brake fluid with no leaks.

I'm sticking to it.

 

Bill Harmatuk

Edited February 8, 2018 by Bill Harmatuk (see edit history)

[retiredmechanic74]

Hey Guys on this brake subject........It's your investment and it is your judgement call. All I can say is you work on one car and I have worked on more then I can count and in my case my butt was on the line if I did it wrong. Good luck to all and I hope Spring is early.

[Spinneyhill]

@retiredmechanic74  I wonder if we are talking of the same thing. The wikipedia picture of simplex brakes shows more braking effort on the forward or leading shoe. I am thinking of simplex brakes with one double ended cylinder and fixed anchors. On the LHS of the car, the wheel is rotating ccw when it moves forward as I look at the car with front to the left. The brake shoes are pushed in the same direction. The force vectors on the front (leading) shoe add, increasing the braking effort. On the trailing shoe, the force vectors subtract, reducing the force of the shoe on the drum. Wikipedia shows a simple diagram of the effect - the black shadows show the braking force exerted.

I suppose one could put the larger end of the cylinder on simplex brakes on the trailing shoe in an effort to even up the braking effort, but those I have worked on, from the '30s, did not allow the cylinder to be on the other side because of the bolt pattern.

 

Later brake systems are also shown in the diagram, and it is clear that for the two servo types, the rear or trailing shoe does most of the work. Are you thinking of these types?

[retiredmechanic74]

59 minutes ago, Spinneyhill said:

@retiredmechanic74  I wonder if we are talking of the same thing. The wikipedia picture of simplex brakes shows more braking effort on the forward or leading shoe. I am thinking of simplex brakes with one double ended cylinder and fixed anchors. On the LHS of the car, the wheel is rotating ccw when it moves forward as I look at the car with front to the left. The brake shoes are pushed in the same direction. The force vectors on the front (leading) shoe add, increasing the braking effort. On the trailing shoe, the force vectors subtract, reducing the force of the shoe on the drum. Wikipedia shows a simple diagram of the effect - the black shadows show the braking force exerted.

I suppose one could put the larger end of the cylinder on simplex brakes on the trailing shoe in an effort to even up the braking effort, but those I have worked on, from the '30s, did not allow the cylinder to be on the other side because of the bolt pattern.

 

Later brake systems are also shown in the diagram, and it is clear that for the two servo types, the rear or trailing shoe does most of the work. Are you thinking of these types?

No, that could be a specific type of brake system I'm not familiar with. None of the shoes are floating, that system is before my time although I have worked on two cyl. systems. The duo-servo is the system I am most familiar with, which has been used widely on later models. The duo-duplex is a two cyl. system but was not as effective as the duo-servo. The difference in todays brake system is ( It's still a basic duo-servo) except it is allowed to move into a upward and backward stroke because of the star adjuster and therefore the primary and secondary shoes were introduced into the equation.  

[Spinneyhill]

1 hour ago, retiredmechanic74 said:

No, that could be a specific type of brake system I'm not familiar with.

 

Thank goodness. I thought I was going potty. So we are both right and that is an excellent outcome.

 

In vehicles with  Simplex brakes, often the trailing shoe is shorter at the bottom. There is very little difference in braking effort, but the saving in shoe lining can be significant - 1" x 45,000 cars x 4 shoes = quite a lot of lining material!