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Whoa No Brakes!

ekamm

Jedi Warrior
Offline
Decide to work on my TR3 today. Wanted to adjust rear brakes, the handbrake wasn't really doing it's thing. Then decided to check the shoes to see if they needed replacing. And I was curios to see the mechanism never having pulled off the hub. After figuring out how to get the hub off (the work shop manual no help). I pulled the hub and the pad part of the lower shoe falls out. There was a little brake fluid in the drum so I figured that it had eaten the adhesive off. I had an older shoe that came in a box with the car so I wrestled and figured out how to change it. This is where the stupidity comes in, I pressed on the brake pedal to see the action of the cylinder and it moved after pushing a few more times there was a decent stream of fluid coming out and I assumed the seal was bad. When the drum wouldn't fit I noticed that I had pushed the plunger out too far and pressed it back and put the drum and wheel back on after adjusting. Went to drive it home and when I pushed on the pedal it was like bleeding the brakes slow pedal all the way to the floor. Large puddle under the wheel used the hand brake home.
So my cylinder no longer available, no repair kit. Looks like the only option is to change to an aftermarket cylinder and replace both. Is that my only choice?
 
Another way to go is to have the cylinders sleeved. White Post or Apple Hydraulics come to mind.

Cups should be available by size thru NAPA.

Are you SURE there aren't kits available?
 
Everything that I saw in my commission no. range said that it was no longer available. and superseded to a replacement no. I really think that all I need to replace the seal.
 
Before you search all over for a kit in the correct size -- check and see what size yours are -- i.e. don't assume they are as original. Over the years it is not uncommon to substitute whatever size was available (as you note should be the same both L&R) so you may find you have somehting other than that NLA size.

As for the brake shoe pad falling off -- are you sure it was brake fluid that caused it? I ask as I have had a diff oil leak produce the same result (400 miles from home). I always carry a hose clamping plier so I can pinch off that flex line to the rear axle in case of a rear brake leak or other failure and drive home on the front brakes (much safer than relying on the handbrake).
 
TRF has the 5/8" repair kit listed as available, P/N GISP2030.

But I agree with Geo, best to check that your cylinders are, in fact, 5/8" before ordering repair kits. Also inspect the bore to be sure the slave is worth rebuilding. If it's rough or pitted, the new seal will quickly start leaking again (and ruin another pair of shoes).

Note that it is best to replace shoes on both sides as a set; otherwise minor differences in friction compound can cause pulling (sometimes only when cold or hot).
 
Eric,

It looks like your car and mine would be in the same catagory if Moss Motors information is correct (Girling 5/8" bore reported as "Not available for many years." and N/A on the repair kit). I was surprised at there being 4 different rear wheel cylinders on the TR3's for the Girling brakes (again if Moss's catalog information is correct). Rimmer Bros lists a .70 cylinder and repair kit from TS34401 on instead though and doesn't show a .75 from TS56377 on as Moss does.

Scott
 
Victoria British has aftermarket replacement on sale for $40 for the pair and most kits would be more. I think that I'm going with the new ones and new shoes. There's a place here that will re-manufacture the shoes or new ones? Here's another question , a lot of the diagrams/ parts breakouts shoe the orientation of the backing plate that makes the hand brake activating lever horizontal and mine is vertical. Could some one have rotated it a few hole too far clockwise?
 
HerronScott said:
I was surprised at there being 4 different rear wheel cylinders on the TR3's for the Girling brakes (again if Moss's catalog information is correct).
The front/rear braking balance is affected by the relative sizes of the slaves. After the front disc brakes were introduced at 13046, the factory kept going smaller on the rear brake slaves to reduce complaints of premature rear brake lockup; until they finally reduced the size of the rear brake drums from 10" to 9" at TS56377.

The Moss catalog matches both the factory catalog and what I have found on my various TR3/As. Rimmer, as usual, is a lot more casual about listing approximate replacements without mentioning that they are not 'correct'.

The other part that I find disconcerting is that the original 5/8" slaves had rather deep slots for the shoes to set into; while the generic replacements being sold have no slots at all. When Girling switched from slaves with slots to no slots, they also added pins and springs to hold the shoes to the backplate (and hence in position against the slave piston end). It doesn't seem like it could be a problem; but ...
 
Well all of this still leaves me with the same decision. The Vic. Brit. catalog says that the cylinder is slotted. Does any one have a pic of the rear brakes, under the drum? (hopefully the last generation before they went to 10")
 
ekamm said:
Well all of this still leaves me with the same decision. The Vic. Brit. catalog says that the cylinder is slotted. Does any one have a pic of the rear brakes, under the drum? (hopefully the last generation before they went to 10")

Eric, here's a shot of a 3A, 10-inch rear drum setup.

10inch_TR3A.jpg
 
That looks just like mine except the whole thing seems to be turned maybe one hole counter clockwise. Also I noticed that the steady post that is on moss parts break down isn't visible. I assume that it is there to replace the retaining pin of earlier com. nos. I just want to make sure that everything goes back the way it should be.
 
TR3driver said:
The Moss catalog matches both the factory catalog and what I have found on my various TR3/As. Rimmer, as usual, is a lot more casual about listing approximate replacements without mentioning that they are not 'correct'.

The other part that I find disconcerting is that the original 5/8" slaves had rather deep slots for the shoes to set into; while the generic replacements being sold have no slots at all. When Girling switched from slaves with slots to no slots, they also added pins and springs to hold the shoes to the backplate (and hence in position against the slave piston end). It doesn't seem like it could be a problem; but ...

Nice to hear that Moss's catalog is accurate. I was surprised not to see more info in TRF's catalog.

It's a shame that there aren't at least rebuild kits available for the 5/8" wheel cylinders.

Scott
 
HerronScott said:
It's a shame that there aren't at least rebuild kits available for the 5/8" wheel cylinders.
As I mentioned above, the kits <span style="font-weight: bold">are </span>available.

The problem with TRF is that they simply do not publish a full TR3 catalog. Charles has been promising one for many years, but just never seems to find the time. However, the combination of a factory spare parts catalog plus TRF's various little guides (the Glovebox companion, plus web mini-catalog and hints found in the parts database) work reasonably well.
 
Randall,

Ah sorry, I missed that part of your post earlier with the TRF part number! It's interesting that Moss shows them as not available.

Scott
 
I searched it and they have it. Here's the deal wouldn't I be better off with a new pair of cylinders rather than repairing a pair that may or may not last very long? I'm not terribly concerned with originality under the brake drum as long as the work properly.
 
HerronScott said:
It's interesting that Moss shows them as not available.

Scott

And even more so since Moss Europe shows them available, part no. GRSP2030Z!
 
ekamm said:
I searched it and they have it. Here's the deal wouldn't I be better off with a new pair of cylinders rather than repairing a pair that may or may not last very long? I'm not terribly concerned with originality under the brake drum as long as the work properly.

I'm sure opinions vary, but as long as the cylinders are readily available that's been my approach.
 
ekamm said:
as long as the work properly.
Aye, there's the rub. The factory had a reason for using .625" instead of .7".

And while I've not tried them, there might also be a reason those replacement cylinders from VB are so cheap.
 
And I really thought I recalled TRF having supplied the things a few years ago. Just didn't have current info.
 
TR4nut said:
Moss Europe shows them available, part no. GRSP2030Z!
Oddly, Moss also lists GWC1154 as a 5/8" wheel cylinder, but the listing at British Parts Northwest describes them as a .7", slotted-piston cylinder used to replace the 5/8" cylinder. Very confusing....

Meanwhile, there appears to be a 5/8" Girling type wheel cylinder for the Spitfire MkIV and GT6 and other small Triumphs; I've no idea if it's the same physical size to fit a TR3 backing plate, handbrake lever, etc. Anyone know? I'd think not, but.... ????
 
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