How do you test brakes are working sufficiently?

[Herzlos]

I picked up a utility trailer a while ago with a spring type overrun brake, from pre-1982 as it doesn't have auto-reverse.

I'm not convinced the brakes will work very well on it currently as I can push the trailer about with them on, but I'm stumped as to how I test how well they will actually work.

All I can do at the moment is lift the axle, spin the wheel and use the handbrake to stop it, or try to move it on the handbrake, but that's hardly accurate enough.

The best I can think of to do is take a fairly heavy load somewhere quite and see how it behaves under braking and reversing, but that seems pretty dodgy and unscientific.

This is one of the old ones where the coupling is pushed back against a spring, and the back of the coupling hits the handbrake lever which engages the brakes.

So how would you recommend doing it?

 

[ntsqd]

Given the Morris 1000 bits I suspect that you're dealing with European parts that few of us yanks have any intimate knowledge of. Perhaps a picture or two?

 

[Herzlos]

Ah yes, I'm in the UK. I'll try and take a picture or mock up a suitable diagram to explain how it works.

 

[FJ40-GARAGE]

Accelerate up to 15mph and hit the brakes hard a co-driver as watchmen helps.

Another way is go to a MOT station and get them checked there.

 

[Herzlos]

Apologies for the delay in replying with a picture of the hitch, here it is:

Essentially, on overrun the head compresses against a spring, pushing a rod out the back which knocks the hand brake lever and pulling the brake cable (it's about 30 years old so quite a crude system).

I was hoping to find a solution that didn't involve driving a laden trailer

Incidently, trailer is only rated at about 1500lbs, assuming that makes any difference.

 

[ntsqd]

Not the safest method, but one option would be for a helper to apply the brakes by hand while you attempt to pull the trailer. If the brakes are even moderately functioning it should slide the tires. Then put chocks down behind the trailer tires and observe the mechanism's function while gently reversing. Can try the whole procedure again when fully loaded for confirmation before entering public roads.

Clever system, I like that it also will allow the trailer to twist relative to the tow vehicle beyond the coupler's range while on rough ground. I note that there is a lever that appears to be intended to lock-out the brake actuation while reversing.

 

[Herzlos]

Testing the brakes individually isn't a problem, I can just apply the handbrake (it can lock on) and see if it'll move.

My biggest concern is in verifying that the over-run works; that the brakes are actually being applies when the towing vehicle slows.

If you look at the rod between the hitch head and the spring box, you should see how far depressed I've been able to push the head back manually after greasing (the grease mark about 1/3 in from the right). I'm assuming that brakes won't actually be activated until that is much pushed almost entirely back, and I'm hoping the only reason it doesn't so far is that (a) it's old and needed greasing (b) the trailer will apply for compressive force on over-run than I can by hand and the wheels chocked.

 

[Herzlos]

Excuse the typing errors. I don't appear to be able to edit my own posts?

 

[FJ40-GARAGE]

I would take the lid off of the housing that contents the push rod and have a look inside, guess there is a spring or a kind of damper inside.

 

[Herzlos]

There should be a spring damping the push rod. I'm not sure I'm able to actually get to the spring but I might attempt to dismantle the unit and hope it'll go back together again