Grease on brake magnets

[ren walker]

thanks terry, i'll start checking around.

sorry for the repost, my computer (and sometimes myself) is kind of a spaz.

[Inland RV Center, In]

Originally Posted by ren walker

ok, i've gotten the airstream (now known as the bumblebee) back to our pole barn. Here are some pics of the brake magnet I need, which isn't at all square like I said before. Someone mentioned Napa might have them, but I'm sure KalTire, who was doing the brakes and repacked the bearings, would have checked with them. They said they could not find them anywhere. I am in Canada, so it might not be a standard thing up here. Do I need to get them from a special airstream dealer?

http://www.airforums.com/forum...1&d=1164434719

That magnet has been around for perhaps 50 years, and still is.

They are either for 10" or 12" brakes.

Your 67 trailer used 12" brakes.

It would appear that the servicing dealer is not familiar with older equipment.

Instead of replacing the magnets, you might consider replacing the backing plates. New backing plates (the complete brake assembly) now have oval magnets and are much more efficient than the round magnet type brakes.

Additionally, the oval type magnet backing plates have more stopping power than the round magnet type brakes ever did.

Andy

[RUSSELL]

I agrre with Andy. Replace the whole assembly. It is cheaper and safer to do this than buying the magnets alone. Also surface your brake drums becouse they will be rough and will tear up your new magnets and brake unit.
I did it few years ago and the cost was very reasonable. I did my own labor and the parts with resurfacing the drum ran about 80 dollars per wheel.
Regards Russell in Sunny Tucson Az.

[LI Pets]

A rebuild is fine, replace any rusty springs maybe .50-3$ per wheel, wire brush the backing plate etc. The individual springs can be bought at any local RV place.
It would be good to paint the backing plate etc..

You can replace any or all the magnets, the wear is easy to see and you can test them with a basic volt meter.

One thing that I did is solder the mag wires disgarding the wire nuts.

Clean the bearings put in grease new seals.

Your good for 10,000 miles before a recheck.

Andy, I think, likes to promote new parts

[Inland RV Center, In]

Originally Posted by Lipets

Your good for 10,000 miles before a recheck.

Andy, I think, likes to promote new parts

Most Airstream owners prefer to do the "best" reepairs that can be done, as opposed to "good enough."

Upgrading and/or improving performance is also our motto., especially when it comes to safety items such as brakes.

Some brake parts are no longer available for the old "round magnet" electric brakes.

Not any springs will do, but the correct springs.

Springs will eventually fatigue crack. Replacing all of them is the safe way to go.

If a spring breaks, the first time you back up, the adjuster will drop out, tearing up the brakes and the hub and drum assembly. Trailers that have the very old hub and drums, also have small spindles. That hub and drum assemble has not been available for years.

Magnets cost about half of the cost of a backing plate, and with round magnets, you still have old style brakes, that cannot and do not perform as well as the oval magnet type electric brakes.

Magnets, unless new, must be replaced in pairs on each axle. If not, then you will have a brake pull.

Most often, the magnet arm stud has become loose. If so, that arm has not been available for years.

Bottom line is to upgrade and not take any chances, especially with safety items.

Andy

[LI Pets]

Originally Posted by Inland RV Center, In

If a spring breaks, the first time you back up, the adjuster will drop out, tearing up the brakes and the hub and drum assembly.

Andy, can you explain how that can happen?

[Inland RV Center, In]

Originally Posted by Lipets

Andy, can you explain how that can happen?

That old fact of life called "experience," for over 40 years.

Andy

[LI Pets]

I have over 40 years experience too, can you tell us how that can happen or not?

I don't think it can. But I always want to learn

[TomW]

Originally Posted by Inland RV Center, In

If a spring breaks, the first time you back up, the adjuster will drop out, tearing up the brakes and the hub and drum assembly.

That's odd. When I took posession of my Overlander, two springs on two wheels were broken. There was no shrapnel damage nor any loose pieces of springs floating around. The adjusters were right where they were supposed to be.

IMO, if a spring breaks, accelerated brake wear can occur (which is, of course, not a good thing). Nothing else, though, will happen unless the brakes are criminally out of adjustment.

Tom

[john hd]

i'm gonna jump in here, missed most of this thread since i was away deer hunting.

replacing the whole backing plate assembly is the safest and least expensive way to go. around here you cannot buy just the magnets for the cost of brand new dexter backing plates with new everything including the nuts and bolts!

ususally i get them from pioneer wheel and they are 50 dollars each. no headaches, just new parts.

john

[Inland RV Center, In]

The adjuster springs sole job is to hold the adjuster in place.

If the spring breaks, the adjuster will eventually fall out.

Andy

[TomW]

Originally Posted by Inland RV Center, In

...If the spring breaks, the adjuster will eventually fall out...

I agree IF the brakes are not adjusted every 3000 to 6000 miles.

My point is that it is not an immediate reaction.

Tom

[overlander63]

Originally Posted by Lipets

I have over 40 years experience too, can you tell us how that can happen or not?

I don't think it can. But I always want to learn

There is more than one spring. Andy's scenario is a worst-case, if the spring that holds the bottom of the shoes against the adjuster break, and cause the damage he describes. If the other spring breaks, usually you will wind up with dragging brakes, which you may not notice until you notice the brakes grinding. Another thing I have seen, especially on trailers with brakes that are used occasionally, is the epoxy that holds the friction material will completely delaminate from the base, also known as the table. When this happens, the friction material will ride up over the friction material of the other shoe, causing the wheel to lock. That is another good reason to just replace the whole thing, even if the shoes have a lot of friction material left, the epoxy does have a finite life.

[TomW]

Originally Posted by john hd

...missed most of this thread since i was away deer hunting...

Any luck?

Tom

[LI Pets]

Originally Posted by Inland RV Center, In

The adjuster springs sole job is to hold the adjuster in place.Andy

I've been into cars a long time, I disagree, it primary job it to keep the adjusting wheel from turning freely not keep it in place that is done by notches in the shoe plate.

As far as replacing the whole thing that is not common on cars, they are always rebuilt.

If you check your wheels every 10K you should be in good shape. To have the other possible failures mentioned may only happen if you ignore the brakes for a very long time

[scottanlily]

Ok ,the spring does hold the adjuster star wheel piece from turning ,but if the
spring breaks ,the adjuster does fall out absolutely .It did on my 60 when i first purchased it .going along i heard a squeal from the wheel ,pulled over
in a good spot and proceced to pull the wheel and drum .found the adjuster
in the drum and broken spring for it ,it does not stay in place by itself ,must
have the spring in place ,dual purpouse ,not one or the other .further, the
spring on most all Bendix or other drum brake setups that are self adjusting
(our brakes on the trailers are not) do use the spring to hold the adjustment ,it holds the self adjuster lever tight against the star wheel adjuster so it cannot turn but with the lever and cable mechanism that
actuates it . Any time that spring breaks parts do fall out .The reason for
complete backing plate replacement is for the ease of replacement and repair
and cost effectiveness .If you pull apart your brakes and its all great,but a worn magnet only ,Id replace the magnet only .Most of the time ,it needs
shoes ,or grease contamination and all ,then Id replace the whole backing plate ,its the best way to get a complete job with all new parts .Id go for
peace of mind and a quality job always .

Scott

[john hd]

Originally Posted by TomW

Any luck?

Tom

not yet, i have til dec 10 here....

john

[markdoane]

Originally Posted by scottanlily

.It did on my 60 when i first purchased it .going along i heard a squeal from the wheel ,pulled over
in a good spot and proceced to pull the wheel and drum .found the adjuster
in the drum and broken spring for it ,it does not stay in place by itself ,must
have the spring in place ,dual purpouse ,not one or the other .Scott

I think the adjusters on the older brakes had a shorter notch so it was easier for the works to fall out if the spring broke.

[TomW]

Originally Posted by scottanlily

...but if the spring breaks ,the adjuster does fall out absolutely .It did on my 60 ...

It didn't on my '67. Perhaps a picture would help. As everyone knows, properly adjusted brakes drag ever so slightly on the drums. Study the adjuster with respect to how the shoes rest against it.

The adjuster can not immediately fall out on an original 1967 backing plate when the spring breaks if the brakes have any modicum of adjustment.

Tom

[markdoane]

Originally Posted by TomW

. Perhaps a picture would help. Tom

Here's pictures of the old brakes with the shorter adjuster, and the new Dexter brakes with the longer adjuster.

The earlier brakes shoes also appear to have less toe, so if the spring breaks it has less of an overhang to hold the adjuster from falling out.