1972 SRS 111 BRAKES.

[GUYZER90]

Hi Folks

Your help is needed !! , last month i went for a trip to ireland to re chassis a 1972 srs3 diesel safari lwb fitted with sailsbury rear axle.

Re chassis all went according to plan with no real issues , untill it came to bleeding the brakes , it has had all the wheel cylinders replaced ,all the shoes replaced , master cylinder replaced and all brake lines replaced , being an early srs3 it dose'nt have a servo.

Rite we bled the brakes as it sais in the book of words, adjusting them all up solid ,starting with the wheel nearest the master cylinder and working round , have a pedal but very low (nearly on the floor} 1 pump and the pedal is rite up the top where it should be.

So thinking there is more air in there, bled it all again , exactly the same!! still on the floor.

So , time had run out and we had to return home leaving the landy with iffy brakes , since then it has spent 3 weeks at a local garage in Donegal for them to try and sort this problem out with out any success , they have checked all shoes and return springs to make sure that we assembled it all correctly , they have changed the master cylinder for a genuine Girling instead of the BRITPART 1 we fitted and changed front cylinders for yet another new set and pressure bled the system , and guess what they still have the same symptom.

Any body got any ideas what it could be. please please please

Regards Guy.

[rtbarton]

Try to isolate where the problem is by clamping the flexibles one at a time.

You really need to flush the fluid through quickly as the ports on the front cylinders aren't at the top so you have to cause plenty of splashing to scoop the air out.

Do the LH one first with the rear & RH flexibles clamped, when you get a hard pedal remove the clamp off the RH front and bleed that one, then when you get a hard pedal remove the clamp off the rears, do the LH rear first then the RH rear.

Finally centralise the PDWA if fitted and adjust the shoes.

[GUYZER90]

Cheers for that, all ideas greatfully appreciated and will be fowarded to ireland .

Cheers Guy.

[ludylandy]

You say that you have a good firm pedal on 2nd pump. If there was still air in the system the pedal would be spongy on 2nd pump but if it's all been pressure bled by a garage they should've got all the air out.

Assuming the system is free of air either the master cylinder is not moving enough fluid into the cylinders or the shoes are sitting too far away from the drums to make contact with them on the first push. So questions I would ask are as follows.

Is it the correct master cylinder?

Are the shoes correctly adjusted?

Are the drums badly worn?

One other thing I did wonder about was the new brake lines. Does copper pipe come in a variety of diameters and have you used the correct one? If the pipes are too big the master cylinder wouldn't be able to move enough fluid. Perhaps someone else will know the answer to that one.

Good luck in getting to the bottom of the problem.

Adrian

[Phil Hancock]

With the 2ls front brakes it bleeds best if the rear hose is clamped off and the pistons in the front wheel cylinders are G clamped fully in to reduce the volumne to minimum, pressure bleed fronts till it runs clear then remove the clamp on the rear and give that a quick bleed to be sure then refit the front shoes and drums. Adjust up and you should have brakes.

[rtbarton]

With the 2ls front brakes it bleeds best if the rear hose is clamped off and the pistons in the front wheel cylinders are G clamped fully in to reduce the volumne to minimum, pressure bleed fronts till it runs clear then remove the clamp on the rear and give that a quick bleed to be sure then refit the front shoes and drums. Adjust up and you should have brakes.

Dead right, I forgot about that dodge! I made some special clamps out of old brake shoes to do just that.

[Greg S]

LWB right? And nobody else has spotted the problem yet? The locating pin for the snail cam on the rear brake shoes is located ever so slightly different from one shoe to the next. Two of your shoes have the pin just a few mm closer to the shoe than the other two. You have to have one shoe of each on each side then you hold a shoe up to it's proper spot and see how far the pin is from the snail cam. One shoe will line up "just right" with the front snail cam and the other will line up for the rear cam. The pin is just a few millimeters different from one shoe to the next but it makes a heck of a difference as you are finding. Hard to see by eye till you catch it, then it stands right out for you but only as you are comparing two shoes side by side.

Commonly know by people with LWB.

[rtbarton]

Does that apply to the Salisbury axle?

Also the OP states the pedal pumps up on the 2nd stroke, suggesting air in the system.

Clamping the rear flexible will eliminate that cause.

[DaveSIIA]

Rite we bled the brakes as it sais in the book of words, adjusting them all up solid ,starting with the wheel nearest the master cylinder and working round , have a pedal but very low (nearly on the floor} 1 pump and the pedal is rite up the top where it should be.

So thinking there is more air in there, bled it all again , exactly the same!! still on the floor.

The brakes should be bled with the adjusters backed off fully (pistons pulled right back in to the cylinders). This gives the least volume in which to trap air and makes bleeding much easier.

Once you have bled all the air from the circuit, then set about adjusting the shoes and centring them in the drums.

[Phil Hancock]

http://www.expeditionlandrover.info/landRoverFAQ/FAQ_rearbrakes.htm

[GUYZER90]

Cheers for all the ideas chaps , i will let you know the outcome as soon as i know.

Regards Guy.