If you service your own trailer 4 tips for you.
I have an SBS trailer which uses Al-Ko brakes, which in my opinion are a poor design, prone to corrosion, and unsuited to marine trailers.
For probably 5 decades trailer manufacturers have used rod-operated overrun auto-reverse brakes; while acceptable for caravans, certainly do not respond well to being submerged in salt-water.
Corrosion of all parts is very rapid and often total de-lamination of brake shoes, on the latter Al-Ko shoes are very susceptible to this, and when repeated failures were reported Al-Ko said they should not be submerged in salt water! (On marine trailers)
3rd party shoes from Taunton Trailers are much better quality, and cheaper.
The US (and others) have moved to hydraulic brakes, electric operated brakes (arrrrgh) and even stainless steel disc brakes.
UK trailer manufacturers have yet to join the 21st Century.
Anyway the 4 tips
#1 From new
Paint the back plate front & rear, and metallic part of shoes & drum with 2-part epoxy paint. Obviously not putting paint on stub axle mating surfaces, or where friction shoes touch the drum.
As well as enhancing protection, makes annual clean for service much easier.
#2 Masking Tape
When reassembling the brakes first put a layer of masking tape on friction surfaces of the shoes, as you won’t keep them clean otherwise.
#3 Fitting the brake shoe spring retaining clips (plates)
I have had many trailers with Al-Ko brakes and they were all difficult to install the plate spring on one side …. This is the side which is obstructed by the suspension swing arm. On the SBS trailers, this is very difficult, as you cannot even get a finger between the gap.
Here is a method I figured out that works.
1.use a wood work clamp, one part behind the swing arm, the other on the face of the spring . Line spring so the ‘hook’ faces vertically upwards.
2.Use a telescopic magnet to hold the plate ‘end on’
Position into place from above, then slowly release clamp, closing Spring hook into the appropriate holes in the plate.
Using a needle nose pliers, at the face of spring grab the central rod and rotate 1/4 turn to put sori g plate into correct location (horseshoe facing out)
This may sound convoluted but takes less than 3 mins …. Having spent a great deal of time trying to get plate on otherwise this is very quick, and saves a lot of swearing as you keep having to find & pick the clip up.
#4 Lanoguard
once all assembled spray everything with a light mist of Lanoguard, both front and back of brake plate, leave it a few minutes then peel the masking tape off the shoes, I apply film of Lanoguard on stub axle and bearing mating face, but none when shoes touch the drum.
Also coat outside of the drum when refitted (and the metal part of wheels)
https://www.lanoguard.co.uk/
Just a warning note, if you have Al-Ko hubs with parallel sealed bearings rather than pre-load taper roller bearings …. Be prepared.
The one-shot flange nuts must not be reused, and to tighten then back up you need a torque wrench at 290 Nm, that is a very substantial force, way above the torque wrench that most will have.
In my case I have a suitable torque wrench, and have to add a 4’ length of steel tubing to allow me to apply enough force.
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