Service Brake Cross Shaft

petew

petew

Senior Member
Question,
The service brake cross shaft has the split bushings on the ends of the shaft and these are held onto the shaft and mounted to the frame by the brake cross shaft to frame brackets.
Does the shaft pivot within the bushings or do the bushings pivot within the frame brackets ?
Upon disassembly I discovered mine were bone dry and there was corrosion on the shaft ends where the bushings ride .
There were some witness marks on the insides of the frame brackets that indicated movement .
 
The cross shaft moves in the bushes. There being no facility provided to lubricate them, they do dry out. I give them a squirt of a Teflon penetrating spray when I grease the car.
 
Pete, lets start from the beginning on this.

The original bushings were not split bushings. Originally they were a solid bushing that used a cotton woven inner liner. (Below is a link to the original style) The brakes when properly adjusted only rotate the cross-shaft about 15° or less, -so lubrication during the rotation is not that big of a deal however the Ford service mechanics usually oiled the insert wicks which kept enough lubrication to do the job. Just like many other components, these were a wear-item that after years of service, they were to be replaced. Unfortunately, many restorers took the easy way out and used the split bushing which are junk IMHO.


https://www.snydersantiqueauto.com/product.htm?pid=977599&cat=0
 
A lot of folks shy away from removing the arms due to the rivet situation. Folks that have the tooling and the know how will remove them. It allows a better clean up of parts for full restoration.

Back in the day folks just wanted to fix it quick and go so the split bushings came along to facilitate that.
 
Well Brent I appreciate you advise and your honesty.
This is my first stock model A and I am learning about corrosion and mechanical brakes !
The brake crossover is just one of the parts that requires attention .
The drums were steel and way oversized , the cam assemblies for the rear brake actuation were seized , the shafts turned but the floating bar that moves the shoes were rusted solid.
As a result I had Randy Gross set me up with cast iron drums front and rear with fresh shoes.
I will be studying my options will the cross shaft before proceeding.
 
Petew, I think Randy can restore your X shaft too. Else, Snyder's can. I was lucky; our car didn't need so much.

Good Luck, have fun learning.
 
There is no question that restoring the brake cross shaft bushings is challenging. When I got my first Model A in 1964 and still a student, my Town Sedan bushings in the cross shaft were very loose. I made a crude repair by taking a small length of copper pipe equal to the length of the bushings and cut it in half to make a couple of split bushings. I heavily greased the bushings (pieces of pipe) and then hammered them in between the worn bushings and the steel shaft. They went in tight but when I worked the shaft back and forth they eventually broke in and made a perfect repair. I did not have to take out the rivets and I sold that car 34 years later and the cross shaft was still very serviceable.

Advance to the present and now I am restoring a 31 Cabriolet. Cost and time is not an issue. I did buy the split bronze bushings and removed the rivets. I liked using the split bronze bushings because I was able to fit them to the existing, worn shaft. I found that I had to install shims between the bushings because if they were installed as is, the shaft was locked up tight when assembled the unit. By using shims, you have the capability to place the shims so that you have a perfect snug but smooth moving cross shaft fit. Don't forget to grease everything before you put it together.

One last step, you have to install the rivets. I found a neat trick to do this, that is if you have access to a mig welder. Assemble everything, insert the rivets of the correct size and place the assemble on the conrete floor well supported in a position to hammer the rivet. Set the mig welder on high and heat the end of the rivet for about 4-5 sec. Quickly pickup your rivet setting tool and give it a quick firm whack. That rivet will form perfectly, with a nicely rounded squashed end. It is better to hit it a little harder than necessary to complete the forming process. I also used this process on the front and rear spring clamps. Oh, this restoration stuff is so much fun!! Ed
 
Dino's A said:
Now your talking. Especially brass, needs lubrication!
Click to expand...

...or does it? Maybe some clarification on what kind of lubricant??

There are definitely dry lubricants that are designed for not attracting dirt and grit that would cause premature wear on the bushing. Grease applied through a Zerk fitting is likely an inferior idea, -especially when there is not a seal to prevent dirt from entering the pin area. Farmer and Heavy Machine operators have known this for years which is why they constantly grease their equipment as a way of letting the newly applied grease plush out the dirt & grit that has worked its way into the grease that surrounds the pin.

A better choice IMO is a product called Slip Plate Dry Graphite. Because the bushing in this application (-note it is a bushing and not a bearing!) carries very little load, the graphite would be well suited for this application. One proper application of the Slip Plate would likely last for many, many years of driving.
 
I would clean up the bearing surfaces before installing the split bushings.
All I can say is my experience. I use split bearings on my cross shaft. I installed them 21 years and 40,000 miles ago. I coated the bearings with grease when installed and I greased them again about 10 years ago. The cross shaft still functions properly. JMO
 
On Bert’s Model A parts, they sell a nylon bushing and they suggest it can be cut and placed in hot water to soften it. They say the bushing can then be slipped over the cross shaft. Does anybody have any experience with this repair or have any technical tips how to install these bushings without removing the levers? Steve at Bert’s claims there is a YouTube video but after an exhaustive search, I cannot find any opinions.
 
I was told same cut on a 45 deg and boil to soften and they'll slip on. I'm looking for the same video info but I've found nothing yet.
 
I have these nylon bushing on both my Model A's. The first se was installed over 20 years ago and still works great. The other set was installed about 5 years ago, like first ca,r it is also working great.
I cut them at 45 degrees, put in hot water to soften, cleaned and greased the bearing surface when I installed them. I also turned the cut to 3 O'clock to help compress the bushing when I mounted it in the car.
 
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