Rear brake locking after new brakes.

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Pistons can also stick when new, a drip or two of brake fluid dribbled on top of the piston near the seal will help, I have had it where they stick a knatts cock and return the piston further back in than it should travel normally, leaving you with poor brakes until you pump the pedal a couple of times.
 
As the truck was stopping inline I will let them bed in a bit before I go too over the top. I will have a look at the pipes and look for kinks and see if I can identify any potential restrictions.
 
I have just swapped the rear axle case on my Defender 90 and at the same time I gave it a bit of a refurb. It's had new (refurb) case, new bearings (Timken), new calipers and discs (Britpart), new cunifer brake pipes (by me) and new Delphi/Lockheed pads. I have blead the brakes and the pedal feels good.

Took it out for a short drive today to test the brakes. The pedal was firm and it stopped so I decided to take it on the road. I slowly built up speed whilst testing the brakes. It stopped well without pulling so I deceded to try to get it to lock up.

So on pushing hard I got a rear wheel to lock. It was the rear left. I tried again and the same. Whilst doing this the truck did not pull, but I don't know if this is normal.

The road surface was a decent tarmac and dry. Front tyres are 6 month old General Grabber AT3s and the rears are older General Grabber TRs.

I was probably doing around 25-30 mph when testing.

What are your guys thoughts?
Brake pipes
View attachment 264372

View attachment 264373
Bleed, Bleed, and pressure bleed again! Regardless of hard pedal. I did a full end to end brake lines, braided flexi's, master cyl and compensator replacement....pesky micro bubbles, after a few miles of testing........ask me how i know? lol
 
There's an awful lot of air can hide in a Land Rover braking system. I've found that it helps to let it settle overnight and then bleed some more the following day.

The standard Land Rover brake pipes have a lot of sharp bends in them. Some seem particularly gratuitous, like the 'step' in the metal brake pipe that goes from the centre of the rear axle to the nearside rear. Having replaced all the metal pipes with my own over the years, with much softer bends in them (and only where necessary), I find it bleeds through somewhat more easily.
 
I have just swapped the rear axle case on my Defender 90 and at the same time I gave it a bit of a refurb. It's had new (refurb) case, new bearings (Timken), new calipers and discs (Britpart), new cunifer brake pipes (by me) and new Delphi/Lockheed pads. I have blead the brakes and the pedal feels good.

Took it out for a short drive today to test the brakes. The pedal was firm and it stopped so I decided to take it on the road. I slowly built up speed whilst testing the brakes. It stopped well without pulling so I deceded to try to get it to lock up.

So on pushing hard I got a rear wheel to lock. It was the rear left. I tried again and the same. Whilst doing this the truck did not pull, but I don't know if this is normal.

The road surface was a decent tarmac and dry. Front tyres are 6 month old General Grabber AT3s and the rears are older General Grabber TRs.

I was probably doing around 25-30 mph when testing.

What are your guys thoughts?
Brake pipes
View attachment 264372

View attachment 264373
PS admire your bravery using those widow maker axle stands lol
 
Although the calipers are new, one could be sticking or not travelling as far as the other. I'd drive around a bit more before doing anything just yet.

As per @mick the builder , where all the components are new it's best to bed them in first. Then go back and recheck.

Nineties/90's have a tendency to lock up the rear n/s as this is the corner with the least amount of weight/load. When I rebuilt mine...new drums, pistons, springs and Mintex 1144 shoes, pipes, the drums pre-scuffed and both sides set up/balanced to within a gnats cock...I can still lock up the rear n/s wheel under very heavy braking. Luckily this has only happened once, but it did happen on the M4 when a number of cars in front decided to play silly buggers at a junction. Importantly, the Ninety pulls up quick and straight.
 
That is some very neat brake pipe work, i would be very pleased with that.

As for the brake locking, I would go with the run it and see suggestions.
I have seen new calipers with dry seals, so you apply the brakes the pston moves out, as soon as you let go of the pedal the piston returns but to far back in its bore as the seal pulls it back in, maybe this is happening with the non locking side, ie the locking side is compensating, a few small drops of brake fluid on the piston allowing the fluid to run around has soretd them for me in the past.
 
PS admire your bravery using those widow maker axle stands lol
I do use these as they are all I have and didn't know there was an issue with them. Are they known to fail and if so, how?

I really don't want to be using stands that have a risk of failure.

I would normally leave the jack in place at the side of the stand, but these photos are from when I did my axle case swap and brake change, so the truck is bolted to a frame at the back - but that's not the point here as I want to know the issues - I don't want to be supporting the truck on my chest!!!
 
I do use these as they are all I have and didn't know there was an issue with them. Are they known to fail and if so, how?

I really don't want to be using stands that have a risk of failure.

I would normally leave the jack in place at the side of the stand, but these photos are from when I did my axle case swap and brake change, so the truck is bolted to a frame at the back - but that's not the point here as I want to know the issues - I don't want to be supporting the truck on my chest!!!
Those stands are unsafe due the fact that the locking clip can be easily knocked, by a leg / arm tool when working under a vehicle, some of this type do have an extra safety pin due to the dangers and history of collapse ( pic on left ) but not all. Even then I would not use them at all.
The safer option is axle stands that have a through pin. (Pic on right)
Plenty of stuff on you tube about how unsafe the first type are

Screenshot 2023-07-11 at 12.31.23.jpg
 
Those stands are unsafe due the fact that the locking clip can be easily knocked, by a leg / arm tool when working under a vehicle, some of this type do have an extra safety pin due to the dangers and history of collapse ( pic on left ) but not all. Even then I would not use them at all.
The safer option is axle stands that have a through pin. (Pic on right)
Plenty of stuff on you tube about how unsafe the first type are

View attachment 292711

I have a pair of each.
I must admit I am careful with the "ratchet" 1s (mine don't have safety pins) as to how I place them and lever direction. But (i havent tried) how difficult would it actually be to lift that lever with the weight on it?

I am lucky in that I have a pit so the axles stands dont have to come out often to work under the car. If I do have to like removing a wheel it always gets chucked under the sill of the car;) . And I have a quite few 6x6" wood blocks that get used too.

J
 
I will have a look at mine today and assess if I can add a safety feature. I could potentially add a swing down tab that covers the lever to prevent lifting inadvertently, but I will need to look at if its possible first. I am always careful and mindful of the position of the lever, but then accidents happen due to unforeseen circumstances!
 
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