Thread: So, 101 drum brakes DO work!!

Originally Posted by Blknight.aus

assuming the proportioning valve is working correctly you should ALWAYS have a small percentage of pressure going to the rear wheels even if they are completely off of the ground. Theres a few reasons for this and my favorite is that it gives you something on the brakes at the back just in case the fronts let go.

There is a weight shift in the vehicle to the rear which opens the proportioning valve making the rear brakes more effective.

Garru

Originally Posted by garrycol

Oh, do you like your box style brake fluid reservoir. I hear they work OK but do not look as good as the originals .

Garry

It is fine, but you are right - doesn't look as good as the originals, but it is compact and allows good visibility of my new gauges, and allows me to mount the tacho where I have. They may have fitted with the originals, but the photos I have seen shows it would be tighter. Not sure if it will suffer from UV exposure at all - time will tell.

To fit a series booster you need to change the rod for the booster from a series one and reuse the one for a 101...........I think.........I haven't needed to do that sort of a job yet.
To get improved vacuum assist, you need stronger vacuum or a bigger surface area of booster diaphragm for the vacuum to work on.
Neither are easy.
There is not much room to fit a bigger booster under the dash board.
To improve vacuum you could use a diesel type altenator with a vacuum pump on the end.
You could fit a remote PBR brake booster on the chassis somewhere .
Another option is to improve the brakes themselves.


If you really want to get a 101 to stop is .........
Drop the wheels off and then the brake drums and check for leaking hub oil seals and wheel cylinders........it is a good safety check and easy to do.

101s tend to get oil or fluid on the shoes.
Wear limit on drums with standard shoes is only 1mm O/S
If all is well throw it back together and do a good brake adjustment.
I found with correctly and freshly adjusted brakes the 101 stops well and will reduced pedal effort.
If you can get the pedal to start working early as possible in its travel, pedal effort seems to have abit more leverage over the shoes than with brakes slightly out of adjustment.

As my post said, I'm not after better brakes - they work fine, I just want to reduce the pedal pressure I have to apply if possible so I don't wreck my knee - I already struggle sometimes to get into it, so I want to help my cause as much as possible. As I've just posted on he thread Garry gave me a link to, AJ has a D1 booster fitted to his, but I didn't look how he did it, but he is one smart cookie, so if there was a lot of fabrication, he would be able to do that whereas I may struggle a bit.

I have had the wheels off it, and the brakes are A1 as are all the mechanicals on this unit. The wheel cylinders look almost new and there are no leaks. Brake shoes are almost new as well. It doesn't pull one way or the other at the moment, so not even an adjustment is required. I have had to stop in a hurry once or twice, and it pulled up better than I expected, but boy was I leaning on the pedal!

Originally Posted by vnx205

No, because if you braked while travelling backwards, there would be weight transfer to the back wheels, so the valve would open.

This is quite funny......... Yossarian would understand.

The rear brakes mightn't work until there is enough weight transfer due to the rear brakes working.

DL

I do not think the vacuum surface area on a disco booster is much different than a 101s unless it is a double type.( I suspect the fitting of a disco booster is only to replace a unrepairable 101 item which are no longer advailable)
I can not see a double/tandem type which is much longer than a 101s fitting in without major work.


Hows the rear brakes working.........If you cannot bleed them, most likey the load sensing valve is jammed up.........common problem.

Make certain the basics are correct, before the spending time and money on the other stuff.

Thanks Ron. The D1 booster is a double diaphragm unit, and is not small, so that's why I was wondering if anyone had managed it, but as mentioned I know of 1 example that I need to go and have a close look at.

Back brakes look like new as well, but I haven't tried to bleed them, so I have no idea if they are actually doing anything - I will try and bleed them and see.

Gav - if you have your drums adjusted up right it might feel that you do not have a lot of braking assistance but I can assure you that when the time comes and the pucker factor kicks in when braking heavily the standard booster does its thing and provides more than enough braking effort to lock wheels - the issue is what direction you will be going and this is not a booster issue.

I was looking a the double diaphram D1 booster to deal with the heavier requirements of the disk brakes. Clearly can be put in with a bit of mucking around but an additional in line booster just on the front brake circuit would be easier to do and for about the same cost.

Garry