Replacement brakes for 1983 scamp 13?

[FJ40Jim]

Been searching for hours, but can't find any info, so here's the question:
Is there a source for replacement brake assemblies for a 1983 Scamp 13 that came from the factory with 7" electric drums?

Backstory:
When I got the Scamp a few years ago, the droopy torsilastic axle was replaced w/ a new Dexter 2200# axle w/ brake flanges. The original brakes & drums were moved over to the new axle, since the brakes did not look like they had been used. With new Timken bearings, a good brake controller and correctly adjusted brakes everything worked great for 2 years.

On our trip a few weeks ago, a squeaky sound was heard from one side of the trailer brakes, and that hub/drum was too hot to touch. Pulling the drum revealed the shoe linings had failed their glue bonds, the linings banged around inside the drum, knocked the return spring and adjuster loose, which got stuck between the drum & shoes. It was total carnage of brake shoes, spring & adjuster on that side. Drum was OK, just had a couple grooves. Other side was about to suffer the same delaminated lining fate. Removing loose pieces from bad side and disconnecting brake controller fixed the problem so we could continue on our trip.

The original shoes measured 7 x 1-1/2". The new loaded brake assemblies all measure 7 x 1-1/4", but everybody said they would fit, the shoes would just be not quite the width of the drum. Well, they are wrong. The backing plates themselves are dramatically different. The new backing plates are much more offset, so they pull the shoes about 1/2way out of the drum, and the magnet can't reach the inner face of the drum.

What's stumped me is that this is a new Dexter axle w/ standard brake flanges installed. Why do the new brakes not line up, and where does one source the correct brake assemblies?

Any info is much appreciated.

[Darwin Maring]

Try Northern Tools
Tow Zone Electric Drum Brake Kit — Pair, 10in., Model# 56125 | Drum Brakes| Northern Tool + Equipment

[floyd]

Your original axle had a straight 1" spindle, a new one has a straight 1-1/16" spindle. The visual key is that the magnets are different shapes.
Good news is that you can buy a complete brake kit including bearings and seals for well under $200.

[FJ40Jim]

Thanks for the responses guys.

Some updated info: The original brakes on my 1983 Scamp are 7-1/4" diameter x 1-1/2" wide Fayette electric brakes. I've never heard of them before. They were going obsolete in 1983, so there seems to be zero parts availability now, 32 years later. If it was only the shoes that had de-bonded, they could be relined and the brakes would be ready for another 30 years, but there is still the issue of the destroyed adjuster & return spring. It looks like those parts can be fabricated by copying the good parts that remain on the other side of the trailer. I will post more info here as I get it.

[FJ40Jim]

Further brake updates:
Nobody in central Ohio does automotive brake relining anymore, only giant semi-truck shoes.

Found a very friendly shop in Indiana that says it's no problem to reline & radius grind these little shoes. Should be $60 for the set of 4.

Their page:
http://brakematerialsandparts.webs.com/

Will post up when the parts are back & reinstalled.

[Perry J]

Originally Posted by FJ40Jim

Further brake updates:
Nobody in central Ohio does automotive brake relining anymore, only giant semi-truck shoes.

Found a very friendly shop in Indiana that says it's no problem to reline & radius grind these little shoes. Should be $60 for the set of 4.

Their page:
http://brakematerialsandparts.webs.com/

Will post up when the parts are back & reinstalled.

I just checked in my Northern Tool catalogue and a complete pair of 7 inch electric brakes is $114.99, the same price for 10" brakes.

They come already mounted on a new backing plate that will bolt right up to your axel.

Over the last 10 years I have ordered 5 sets of electric brakes and never had a problem.

Check on line at NorthernTool.com.

Good luck,
John

[stevebaz]

I would think that if you replaced the backing plate and shoe assembly with the new Dexter backing plates you would also have to replace the Fayette drums with the Dexter drums to match the Dexter backing plates and brake shoes.

[Perry J]

Originally Posted by stevebaz

I would think that if you replaced the backing plate and shoe assembly with the new Dexter backing plates you would also have to replace the Fayette drums with the Dexter drums to match the Dexter backing plates and brake shoes.

Drums are generic.
A 7 inch brake takes a 7 inch drum.
I have replaced the brakes on several Scamps I have refurbished.

[FJ40Jim]

Yes, changing from 7-1/4" down to new, smaller 7" Dexter brake assemblies would require buying new 7" drums as well. Since the only thing wrong with the brakes is the bad shoes, we will just replace the shoes for now.

[Perry J]

Originally Posted by FJ40Jim

Yes, changing to new, smaller Dexter brakes would require buying new drums as well. Since the only thing wrong with the brakes is the bad shoes, we will just replace the shoes for now.

I dropped the 1/4.
You will not need new drums.
The brake assemblies are complete with new magnets.

Bolt the backing plates on and hook up the wires.

[FJ40Jim]

I already bought a pair of the 7" brake assemblies. They do not fit the 7-1/4" drums, in either diameter or width.

[FJ40Jim]

Quoting myself:

Is there a source for replacement brake assemblies for a 1983 Scamp 13 that came from the factory with 7" electric drums?

No, because the factory brakes on this trailer are 7-1/4", which is a non-standard size nowadays.

Comparison of OE Fayette 7-1/4" x 1-1/2" shoe and new Dexter style 7" x 1-1/4" shoe.

On our trip a few weeks ago, a squeaky sound was heard from one side of the trailer brakes, and that hub/drum was too hot to touch. Pulling the drum revealed the shoe linings had failed their glue bonds, the linings banged around inside the drum, knocked the return spring and adjuster loose, which got stuck between the drum & shoes. It was total carnage of brake shoes, spring & adjuster on that side. Drum was OK, just had a couple grooves.

This is what fell out when the drum was pulled off. Shoe linings, mangled spring & adjuster.

The original shoes measured 7 x 1-1/2". The new loaded brake assemblies all measure 7 x 1-1/4", but everybody said they would fit, the shoes would just be not quite the width of the drum. Well, they are wrong. The backing plates themselves are dramatically different. The new backing plates are much more offset, so they pull the shoes about 1/2way out of the drum, and the magnet can't reach the inner face of the drum.

This pic shows the different depth of the backing plates. Fortunately, these loaded 7" brake assemblies were super cheap on ebay. Unfortunately they cannot be returned.
Fortunately the adjuster, adjuster plugs, wiring, springs and mounting hardware were used to fix the OE brakes.

[FJ40Jim]

The original shoes were pulled off and mailed to Brake Materials & Parts
in Ft. Wayne, IN.



Shipping each way only took a day or two, and they got the job done in a few days. The shoes were sandblasted, new linings were glued on, painted, radius ground to match the 7.256" ID of the drums. Cost ~$80 with shipping. A week later, these beauties arrived back at the shop:



While the shoes were off at the spa, the other parts were cleaned & serviced.

The actuator arms & magnets were in good shape, just needing cleaning. But I don't like the way the wires went through the backing plate in a solid strain relief. This is acceptable for a table lamp that doesn't go down the road. For a bouncing, vibrating environment, the solid strain relief merely provides a focus for all the movement of the wires. So these were discarded, along with most of the brake wire.



Ox-gard is used on EVERY wire connection & light bulb on the trailer.


Note how the wires are cut in a staggered fashion so the 2 butt splices don't end up right next to each other.


The wire & nylon fingertrap loom was borrowed from the dexter magnets. The nylon loom is VERY tough, and can just lay through the backing plate, so the wire can flex along it's length, rather than flexing right at the backing plate.

[FJ40Jim]

Reassembling the oddball Fayette 7.25" electric brakes.

Actually, the thing that makes these odd is they are a miniaturized version of the 10 or 12" brakes, which is a more robust & effective system.

Apply hi-temp grease to the brake arm pivot and the stamped tab that the center of the brake arm rests against. Place the arm in position and feed the brake wire through the hole in the plate.



Grease the contact points for the shoes: raised bosses on the plate, top pin, square driver on arm... Put shoes in place and then place hold-down springs. The special tool to grab the hold down springs is one end of the return spring. A small vise-grip is handy to manipulate the stiff springs.


Spread the bottom of the shoes slightly and insert a thoroughly greased adjuster, followed by the small return spring. Then use the small vise-grip again to grab the big return spring and get it in position. No pics in process, not enough hands. Note the orientation of the upper spring so coil is away from actuator arm, and lower spring is in holes that are away from the backing plate. Should look like this when done:


Back side should look like this. Verify that the wire is coming through & not kinked, adjuster is accessible through slot, hold-downs are fully seated in plate.

[Carol H]

New dexter hubs can be had for about $50 each - perhaps even a little less on line. Not bad considered having old ones spun/buffed up locally to remove heavy rust was about 3/4 the costs of new ones as I recall at the time I had to deal with refurbishing my Scamps brakes.

I purchased a complete new dexter brake assemble complete with pads for just under $50 per side.

I think $200 for new hubs and brake assembles is an investment well worth making it if it saves messing around and worrying about old obsolete parts - especially for a future owner of the trailer.

[FJ40Jim]

Repeat mirror image assembly with parts for other side.



First QC test: are there any leftover parts? No? Good enough.
Next QC test: check the wiring/magnets for conductivity. Should be the same on both sides. This is close enough, 4.4/4.3 ohms. 3% variance seems acceptable. From this we can calculate the amp load the brakes draw at full power.
4.3/2=2.15ohms total resistance.
14V/2.15= 6.5A max current, or 3.25A per brake.
I thought the OEM 16ga wire to the brakes was small, but 3.25 is well below the 11A capacity of 16ga.






We've checked out the drums and know they are 7.256" on a 7-1/4" nominal size. How will we know if the drums are worn out if there is no service literature anymore? How about reading the face of the drum I've been looking at for a month. doh!



Max Diameter is 7.310 and they are currently 7.255/7.256. Plenty of wear left in the drums.

Also, if I had looked at the drums more closely I would have noticed they are marked HD 7.25 right on front.


Nothing left to do now but reinstall. Hang the backing plates on the trailer axle & tighten the 4 nuts & lockwashers. Reconnect wires, adding some convo tubing where wire passes through the axle bracket. Be sure to use the Ox-gard grease for these crimps that will be very exposed to road splash.



Slide the drum in place, grease the outer bearing, shove it in w/ the D-washer & install nut & cotter key. Whack the new Bearing Buddies in place. (they are replacing the chi-comm dust caps from Vatozone that keep falling off.) Finally, install the freshly blasted & painted wheel with the blasted & painted lug bolts. Tork to 90 ft/lbs, according to stamping right on bolt heads.



One last step, adjust up the adjusters until it is hard to spin the wheel, then back off until they are just barely dragging.

Alright, let's go Scamping! In the mountains! With no fear of steep downgrades!