RV Electric Brake Maintenance - Help

[Bill Robison]

I'm sure many 'board members' do much of your own work, like I do. I would like to draw from some with more experience than myself regarding RV brake maintenance.

My EggCamper is 2008 - I am doing a bearing cleaning and re-pack, new seals, etc. The bearings and shoes are in great shape as are the magnets, but I have a question about the armature surface of the drum - where the magnet 'drags'.

I'm not able to find much of anything online regarding photos of actual surface condition and casual re-dressing or refacing that surface. I would think a good idea to remove any minor imperfections or micro grooves - even though the surface is generally very good? How much 'wear' is acceptable on that surface? How have some of you 'dressed' it up before reassembly?

Feedback of any nature is appreciated - even regarding magnets or wheel bearings (just so contributors don't have concerns about hijacking the post and to help some of the newbies).

Bill

[ken h]

Hi Bill

I have would say if the armature on the drum is in good shape and the magnet surface is somewhat the same , all is well .

I went to get my drums resurfaced and the shop said they did not do the armature surface because the bit on the lathe gets caught on the holes in the drum where the studs go through, the brake surface they would do. They advised me to get new drums, but they were in bad shape

So if they are not that bad maybe run them for the summer and check them in the fall , My new drums were 135.00 ea.

Hope this helps

Ken

[Casita Greg]

Here's a good site for trailer axle/brakes/parts/maintenance, etc. Handy reference link.
Dexter Axle - Trailer Axles and Running Gear Components - HOME

[Bill Robison]

Originally Posted by ken h

Hi Bill

I have would say if the armature on the drum is in good shape and the magnet surface is somewhat the same , all is well .

I went to get my drums resurfaced and the shop said they did not do the armature surface because the bit on the lathe gets caught on the holes in the drum where the studs go through, the brake surface they would do. They advised me to get new drums, but they were in bad shape

So if they are not that bad maybe run them for the summer and check them in the fall , My new drums were 135.00 ea.

Hope this helps

Ken

Thanks Ken and Greg for the feedback!

I have read everything available on the internet - including all the Dexter has to offer, which is not very much about armature surface condition. They mention to 'reface to 120 micro' - but how? and when?

I took matters into my own hands - the way my dad always did. I have a few pieces of heavy 2" solid brass round stock - so I took one that had a very true, flat surface put a piece of 60 carborundum in a U shape and taped it all around. It worked like a charm to dress the drum and the magnets so they were 'smooth as a baby's butt'. I stopped by a local RV dealer to see what the mechanic thought - he said he would put it back together and enjoy the summer! He said they typically don't touch the armature surface and mine looked MUCH better than what they put back together.

Having a pretty serious mechanical background (dad was a Millwright so he designed and fabricated anything) I didn't care for even minor groove lines in the armature surface or the magnets, since under 'load' use the transfer of metal particles will accelerate with continued use and eventually cause severe damage to machined surface. It doesn't seem reasonable to spend $135 + magnets ($20-50 ea) ...about $350 when a little 'elbow grease' solves the potential problem.

After I reassembled the brakes and bearings - I spoke with a friend about it and asked what he would use to redress the surface. He is a die maker - and suggested a Rolok. I'm going to invest in a Rolok arbor to fit in my drill and found new Rolok discs at the pawn shop for $2 each ;-) The nice small diameter disc will work perfectly in that recessed area of the drum!

Hope this give others a idea r to to build upon...

Bill

[Carol H]

Just last week the brakes were replaced on mine and the hubs were taken to a local brake shop who for a small charge put them on a machine they had to resurface them.

[Bill Robison]

Originally Posted by Carol H

Just last week the brakes were replaced on mine and the hubs were taken to a local brake shop who for a small charge put them on a machine they had to resurface them.

Hi Carol -

Electric brake drums have TWO surfaces, which can get scored with wear and require resurfacing OR replacement. Yes, they can resurface the curved part of the drum where the brake shoes ride, but not the flat inner surface where the magnet 'floats' - that's the "armature surface" of the brake drum.

It all gets a bit confusing - hope the pic helps. You might want to quiz your service guy about the condition of the armature surface, since the shoe surface was 'turned' and ask if he resurfaced the 'armature surface' as well. I spoken to several commercial and RV trailer dealers - none of them are capable of resurfacing the 'armature surface'. They put on new drums instead.

Bill

[Carol H]

Thanks Bill they were taken to an expert whos opinion was they only needed a *very* light resurfacing and they did not need replacing. Did not actually look over their shoulder to see all they did. But have had it out on a camping trip since and all works just fine.

[Joe Z]

I just ordered a new 10" Dexter Brake drum with bearings grease cap etc for $82
Joe
http://www.easternmarine.com/DEXTER-...ap-K08-247-94/

[Perry J]

[QUOTE=Bill Robison;248376]Hi Carol -

Electric brake drums have TWO surfaces, which can get scored with wear and require resurfacing OR replacement. Yes, they can resurface the curved part of the drum where the brake shoes ride, but not the flat inner surface where the magnet 'floats' - that's the "armature surface" of the brake drum.

It all gets a bit confusing - hope the pic helps. You might want to quiz your service guy about the condition of the armature surface, since the shoe surface was 'turned' and ask if he resurfaced the 'armature surface' as well. I spoken to several commercial and RV trailer dealers - none of them are capable of resurfacing the 'armature surface'. They put on new drums instead.

Bill. you are going to spend a lot of money needlessly if you keep going to RV shops for your needs.
I bought an old Trillium 4500 to refurbish several years ago that had inoperable brakes. I replaced the entire brake assemblys. Both the interior surfaces of both drums were very rusty so I took them to a local brake shop and they resurfaced the curved area and what you refer to the armature surface. As I remember it cost about $20.00 a drum.
In the last 6 years I have refurbished and sold at least 7 older Eggs. I replaced or added brakes to 5 of them. The Trillium with the rusty drums was the only one that needed resurfacing. I would imagine the average of all the trailers was at least 30 years.
How many miles do you put on your car before you pack the bearings or turn the drums?
John

[Carol H]

Perry raises a good point - how many years or miles does one normally get out of a set of brake pads and the drums?

I'm have a pretty good idea that the ones on my trailer are/were original - 20 years old. The bearings have been repacked each of the 4 years I have had the trailer (and the previous owner suggested they did as well) but it was not until this year that the brakes were replaced as I did not feel the need as everything worked just fine. The pads themselves were actually in pretty good shape and may well have gone another year or more but the condition of the springs etc suggested they were pretty old so I thought it better to replace it all before there was a problem. It was while replacing the brakes that the decision was made to have someone with experence take a look at the drums to make sure they did not need replacing also. The experenced on advised that the drums did not need replacing - only a light resurfacing to remove a bit of surface rust - that was also in the $20 range. As I mentioned everything worked fine prior to putting on the new brakes and I really cant tell any difference between the old brakes and the new. But when I see people with trailers many many years younger than mine replacing brakes and hubs etc it makes me wonder why mine seemed to have lasted so long and is it normal?

[Greg H]

I'm just going to guess that the newer brakes are made in China like everything else.

[Bill Robison]

Hi John -
Judging from the responses coming in - it seems I did a terrible job expressing what I am looking for. I am a DIY guy and was hoping to hear from others who get greasy about 1) how they judge the quality of the magnet surface of the drum (armature surface) & 2) how DIY clean-up, 'dress' or resurface the armature surface of the drum.

Bill. you are going to spend a lot of money needlessly if you keep going to RV shops for your needs.

I don't have work done at RV shops - - I simply stopped by a local commercial trail place and an RV center repair shop to ASK how they address the two above questions. Sort of 'two heads are better than one' thing...

I bought an old Trillium 4500 to refurbish several years ago that had inoperable brakes. I replaced the entire brake assemblys. Both the interior surfaces of both drums were very rusty so I took them to a local brake shop and they resurfaced the curved area and what you refer to the armature surface. As I remember it cost about $20.00 a drum.
In the last 6 years I have refurbished and sold at least 7 older Eggs. I replaced or added brakes to 5 of them. The Trillium with the rusty drums was the only one that needed resurfacing. I would imagine the average of all the trailers was at least 30 years.

Now that's more what I was hoping to hear. How about those who have brakes in really decent shape - what do you do?

How many miles do you put on your car before you pack the bearings or turn the drums?
John

I grew up on a farm where we maintained all our equipment, as most do - as mentioned earlier, my dad was a Millwright and taught me mechanics inside and out - I have to respond to this one since a lot of folks may read these posts (which was also my original intent) who don't know much about brakes and bearings. I lived in an era when we DID clean and re-pack car wheel bearings, but today car bearings are totally sealed from the elements and are typically exposed to regular service, which tends to eliminate moisture and corrosion build-up inside the hub. Trailer brakes, on the other hand, are not sealed units and most are not used in regular service. While in storage or just sitting without being towed often, trailer brakes are at high risk of collecting moisture over time, which causes pitting and corrosion of the bearing cage and at times even the race. Not to mention how much oxidation (rust) forms on the magnets, drum surfaces and internal moving brake springs and levers. All of these are reasons it is difficult to compare car vs trailer brakes and why it is a really good idea to do at least an annual inspection, re-pack the bearings, replace the seals, grease the moving metal parts and generally 'clean-up' all friction surfaces.

I realize that if a trailer is not driven many lifetime miles the major brake components can have a life of 15-20 ...maybe 30 years, but not without TLC (including annual inspections) and replacing some parts along the way.

Please don't think I am contradicting you, since apparently you know what you are doing - this is posted for those who aren't aware why brake & bearing care is so important on a regular basis. If you tow in the mountains a watchful eye is even more important due to the extremes of heat and wear exposure under such conditions. Some people tow their camper 100 miles to park it at a local lake - - others tow 10,000 miles or more in a year under severe service needs. The care and maintenance required by each of these eggs won't necessarily be the same, but I'm afraid some folks on the board may not realize that to be the case? Be safe;-)

I appreciate all the input - let's hear from a few more guys and gals who get 'down and dirty' doing their own brake work ;-)

Bill

[Bill Robison]

Originally Posted by Greg H

I'm just going to guess that the newer brakes are made in China like everything else.

Hi Greg -

Yes, I was surprised to see the original bearings on my Dexter axle were made in China...

Bill

[Greg H]

Go figure.

[Perry J]

Originally Posted by Bill Robison

Hi John -
Judging from the responses coming in - it seems I did a terrible job expressing what I am looking for. I am a DIY guy and was hoping to hear from others who get greasy about 1) how they judge the quality of the magnet surface of the drum (armature surface) & 2) how DIY clean-up, 'dress' or resurface the armature surface of the drum.

Bill. you are going to spend a lot of money needlessly if you keep going to RV shops for your needs.

I don't have work done at RV shops - - I simply stopped by a local commercial trail place and an RV center repair shop to ASK how they address the two above questions. Sort of 'two heads are better than one' thing...

I bought an old Trillium 4500 to refurbish several years ago that had inoperable brakes. I replaced the entire brake assemblys. Both the interior surfaces of both drums were very rusty so I took them to a local brake shop and they resurfaced the curved area and what you refer to the armature surface. As I remember it cost about $20.00 a drum.
In the last 6 years I have refurbished and sold at least 7 older Eggs. I replaced or added brakes to 5 of them. The Trillium with the rusty drums was the only one that needed resurfacing. I would imagine the average of all the trailers was at least 30 years.

Now that's more what I was hoping to hear. How about those who have brakes in really decent shape - what do you do?

How many miles do you put on your car before you pack the bearings or turn the drums?
John

I grew up on a farm where we maintained all our equipment, as most do - as mentioned earlier, my dad was a Millwright and taught me mechanics inside and out - I have to respond to this one since a lot of folks may read these posts (which was also my original intent) who don't know much about brakes and bearings. I lived in an era when we DID clean and re-pack car wheel bearings, but today car bearings are totally sealed from the elements and are typically exposed to regular service, which tends to eliminate moisture and corrosion build-up inside the hub. Trailer brakes, on the other hand, are not sealed units and most are not used in regular service. While in storage or just sitting without being towed often, trailer brakes are at high risk of collecting moisture over time, which causes pitting and corrosion of the bearing cage and at times even the race. Not to mention how much oxidation (rust) forms on the magnets, drum surfaces and internal moving brake springs and levers. All of these are reasons it is difficult to compare car vs trailer brakes and why it is a really good idea to do at least an annual inspection, re-pack the bearings, replace the seals, grease the moving metal parts and generally 'clean-up' all friction surfaces.

I realize that if a trailer is not driven many lifetime miles the major brake components can have a life of 15-20 ...maybe 30 years, but not without TLC (including annual inspections) and replacing some parts along the way.

Please don't think I am contradicting you, since apparently you know what you are doing - this is posted for those who aren't aware why brake & bearing care is so important on a regular basis. If you tow in the mountains a watchful eye is even more important due to the extremes of heat and wear exposure under such conditions. Some people tow their camper 100 miles to park it at a local lake - - others tow 10,000 miles or more in a year under severe service needs. The care and maintenance required by each of these eggs won't necessarily be the same, but I'm afraid some folks on the board may not realize that to be the case? Be safe;-)

I appreciate all the input - let's hear from a few more guys and gals who get 'down and dirty' doing their own brake work ;-)

Bill

Bill, I'm 69 y. o, and have been towing something all of my adult life. I have towed boat trailers, stock trailers, TT's and car haulers.
At the present time I have a sailboat trailer, an ATV trailer and my Scamp. I'm retired so they all get used more than average.
I have lost one bearing and that was on a boat trailer years ago.
I do my own work. My Scamp has about 15000 miles since I checked the brakes and bearings 18 months ago. I just took a short trip with my Scamp. The brakes are working well and the bearings are cool so I won't check them this year. The only time I have had to replace brake shoes was on my 6 horse trailer and a boat trailer that was used exclusively in salt water.
I live in the Mountains and 99% of my camping is boondocking in the Sierra Nevada Mts. or the Mojave Desert in the winter. My favorite areas are about 25 miles on a 4X4 road.
I think new to towing trailer owners worry to much about brakes and bearings which takes away from enjoying the trailer experience.
If you get a little rust on the surface of the brakes while it is stored in the winter. A few stops will clean and polish the drums.
The only time I have ever had rust on bearing or spindle surfaces was on my boat trailer that was used in the ocean in southern Cal. It was caused by a bad seal.
My experience has been that your windows will leak before you lose a bearing or need brake work.
Routine maintenence is a good thing, just don't become obsessive about it.