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+--- Thread: HYDRAULIC BRAKES , HELP PLEASE (/showthread.php?tid=6019)
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RE: HYDRAULIC BRAKES , HELP PLEASE - Colin Reed - 27-04-2021
HI All,
Just an update to my last post,
My advice is the same when drums and shoes are used Regardless of the means of actuation
Colin
NZ
RE: HYDRAULIC BRAKES , HELP PLEASE - Rpm - 27-04-2021
Thank you all so much. I now have the answer in your replies and will now take a look, working my way through them. having the drums skimmed hasn't helped the situation, with new old stock Lockheed brake shoes fitted, and fully adjusted, so will def need oversized shoes or shim the snails. Will measure the drums as stated first.
One question to be clear. Should the brake shoes at rest measure just shy of the 7" brake drums, thus minimal clearance with adjustment for ware, if so I can measure the difference and have oversized shoes made up for starters then move on.
Regards Rob.
ps I will report back when I've sorted this problem for future ref.
RE: HYDRAULIC BRAKES , HELP PLEASE - Stuart Giles - 27-04-2021
Yes, the brake shoes should have minimal clearance to the drum when properly adjusted. The 1/8" movement of the wheel cylinder pistons you reported in an earlier post is almost certainly the reason that you have such a lot of brake pedal movement. Click the snail cams up until the shoe binds and then click one notch back so that you can spin the wheel freely.
RE: HYDRAULIC BRAKES , HELP PLEASE - David.H - 27-04-2021
Which of the snail cams is best/correct? To make better adjustment, my fronts are fine, but rears don't function much on the handbrake, but are ok on the footbrake. If I overtighten the hb cables the stop lights come on!
RE: HYDRAULIC BRAKES , HELP PLEASE - Rpm - 28-04-2021
Thanks Stuart. The 1/8 cylinder movement is with the snails fully adjusted lol. Terrytune posted interesting pics of 2 x different snails so will look at mine and for the bigger type late.
Rob
Terry Any idea of dates for late and early snails ? re your Pictures, the larger of the two may do the job and save a lot of trouble. Great info didn't know there were different types. I'm sure that I have the earlier type, will check later today.
Rob
RE: HYDRAULIC BRAKES , HELP PLEASE - Dennis Nicholas - 28-04-2021
I have gone through a full refurb of hydraulic brakes. The usual ones are the Lockheed. (Morris Minors) and quite a lot of info can be found about the various sizes of cylinders; front, rear, and master; on various MM websites.
Be aware that rear cylinders were 7/8 inch 1948 to 1962 then 3/4 inch 1962 to 1971. The 7/8 inch are generaly no longer available but the 3/4 inch fit directly in place. ..... (I found my rears had one 3/4 and one 7/8 fitted because of lack of knowledge of this info in the past!!!) Less pedal travel but more force though you probably wouldn't notice the difference in either after a change. I have actually changed from the MM master to Mini master cyl. (but easy to mount on a Nippy together with a set of pedal from, I think, a Mini. = get rid of the heavy awkward MM master and get rid of pedal with slots in floor so less draft!.
1962 - 1964 7/8 bore master cylinder as fitted to van is what I removed. and one from a 2016 Mini fitted.
There were also different widths of "standard" shoes.....7 inch by 1 1/4 inch seem to be the ones I have noted as being the ones that make full use of the Girling A7 cast drums width. 948 shoes 1.22 inch wide. (1 1/4 = 1.25 inches.....every little helps!!)
The larger snail cam is actually from the 8 inch brakes (and you will need to slightly file out the slot in the shoe to take the slightly larger pin and the slots in the snail base if you use the larger snail in the smaller snail base. Depends on which cylinder cap you have to take width of snail base. 8 inch brakes MM 1000 and 1098 front drums.
I have used the Silicone fluid for over 20,000 miles since 1988 and had no problems whereas previously had rusting and usual 2 yearly change of fluid.........the Silicon has never been changed since first fill and no paint has been striped as used to be with the other stuff. (Previously away at sea and battle with siezed cylinders every time I came home.)
Of course all rubber seals were new with new Silicone.
My shoes still need packing out to get them to touch drums even though new shoes and with new drums otherwise most of snail used up. This is both front and rear.
Have fun
Regards Dennis
RE: HYDRAULIC BRAKES , HELP PLEASE - Terrytuned - 28-04-2021
The later brake cams 62-71 give an extra 1/8" of adjustment the small cams were used on the rear but soon run out of adjustment so use the front ones. I have seen brake cables adjusted up on MM instead of adjusting the cams which doesn't help pedal travel. I use a Girling 3/4" master cyl I would not use the heavy cast iron lump fitted to the MM and have used silicone brake fluid for the last 20yrs no problem.