Thread: Brakes!!!

Just a stab in the dark, but could it be one of the cups/seals in backwar4ds? I have vague memories of a friend spending a whole week trying to fix a mystery brake problem that turned out to be that

Early land Rovers are notorious for brake bleeding difficulties.

Try and isolate the problem. Begin with the M/cylinder and go from there. Block off the rear brakes by carefully clamping something onto the rear brake hose . Most times its the rear brakes causing a problem, the pipe that goes across the rear axle housing has ups/downs and air becomes trapped in the pipe .

On my 80" , I ended up filling the rear cylinders manually, I removed the pipes and sat a can of fluid high up on the side of the car . I ran the fluid from the can through plastic hoses into the cylinder pipe hole til it ran out of the bleed screw hole . I reconnected the pipes and then ran fluid down the pipe where the flex hose fits until fluid poured out the bleed holes . It worked for me

As series1buff says - clamp off all three hoses for a start. This should give a solid pedal with only a little lost motion. Then release the hoses one at a time, starting with RH front then LH, then back. in all cases you should get a solid pedal with little movement, but increasing as more brakes are brought in. If the pedal is solid, you do not have a bleeding problem, even if it comes solid after pumping, but goes to the floor on the first push.

If this is the case, either there is excessive shoe clearance or there is a leverage problem.

Excessive shoe clearance is caused by incorrect shoe installation, shoes cocked sideways, or adjusters that don't stay put.

A leverage problem will be something mechanical that limits the travel on the master cylinder - have any bits been rebuilt? Is the master cylinder correct?


It could also be a hydraulic leverage problem - if fitted with 11" front brakes, presumably off a 2/3, then it has six wheel cylinders instead of four, and almost certainly needs a Series 2/3 lwb master cylinder.

When actually bleeding, remember that you can bleed from any union by slackening it. Also, you can reverse bleed by injecting fluid into the bleed nipple, and you can also prevent air being stuck in cylinders by removing the drums and clamping the cylinders (or shoes) together to minimise the volume of fluid in the cylinders.

John

Thanks for all the suggestions, I'll start with clamping off the hoses and go from there.
The master cylinder is a correct resleaved unit with the three hole flange, I put this in as it had a series three unit bolted in the flywall. Did the 107 have 11 inch brakes in the front? I thought it was the same master cylinder for both the 86 & 107.
Cheers
Jason

Just a general observation, many master cylinders I have had trouble bleeding have had blocked transfer holes between the reservoir and the working chamber. It might be worth removing the piston and checking that this hole is indeed properly drilled through the new sleeve. The primary piston should be just uncovering the hole in the "off" position. Pedal to pushrod adjustment is critical for the transfer port operation too.

One more thing to check is that the top cam adjuster spring is anchored to the backing plate, not the opposite brake shoe. Yes, I really saw this once on all four wheels (SII).

OK,
I'm making progress, I clamped off the rear flexible hose and after a few pumps had a spongy third of pedal pressure. Clamped off both front hoses as well and have a rock solid pedal!!!
Let off the rear clamp and back to spongy pedal, clamp back on and still solid pedal. I have jacked up the front end and drivers side wheel is difficult to spin, passenger side spins freely.
So tomorrow, front wheels off and check alignment, adjustment etc. Then re-bleed the long pipe in the rear and see how we go.
Cheers
Jason

Originally Posted by Jcrowe69

Thanks for all the suggestions, I'll start with clamping off the hoses and go from there.
The master cylinder is a correct resleaved unit with the three hole flange, I put this in as it had a series three unit bolted in the flywall. Did the 107 have 11 inch brakes in the front? I thought it was the same master cylinder for both the 86 & 107.
Cheers
Jason

From my information the 107 had 11" brakes with two leading shoes on the front. I can't locate whether the master cylinder was the same as the 86/88 or not, but since it was operating six not four cylinders, either the wheel cylinders were smaller or the master cylinder was bigger - and I am guessing the master cylinder was bigger. This may be the basic problem you have.

John