Any difference between brake M/C rebuild kits?

[tdskip]

Any difference in quality between the normal vendors? This is for the early dual bore M/C as fitted on a 948 Bugeye. Was about to order a kit from Moss and it occurred to me I should ask first.

Thanks!

 

[DrEntropy]

Moss kit should be fine, likewise the Beck/Arnley.

Just give the bore a good hone with a "brake hone" tool and visual inspection for pitting before you trust it. A tool like a dental pick on rust spots in there can reveal problems before they bite you on the highway, too. :wink:

 

[jvandyke]

I did mine (early one like yours) 3 times before I realized the bore was pitted too badly and seals were getting chewed up (I had honed it and inspected it but not well enough apparently). I went with a 7/8" out of a later car since 3/4" aren't to be had and resleeving is $$. I certainly think it's worth a $13 kit to try it but if there is any doubt, do it right. Failing brakes aren't very fun.

 

[fordtrucks4ever]

You may be able to bore your existing m/c out to 7/8. Should be much cheaper than a resleeve and then good as a new one. I recently picked up some small bore mandrels for a Sunnen. If my 3/4" m/c doesnt clean up well enough to use, it will be bored and honed to 13/16 first, and then 7/8 if I goof. If nothing works, then it gets resleeved. Right now I dont have anything to loose, since car is a long way from completition and having the equipment to play with, its hard to pass up. In the end, if all I need is a new master cylinder to finish the car, i can justify the expense.

 

[Guest]

You may be able to bore your existing m/c out to 7/8. Should be much cheaper than a resleeve and then good as a new one. I recently picked up some small bore mandrels for a Sunnen. If my 3/4" m/c doesnt clean up well enough to use, it will be bored and honed to 13/16 first, and then 7/8 if I goof. If nothing works, then it gets resleeved. Right now I dont have anything to loose, since car is a long way from completition and having the equipment to play with, its hard to pass up. In the end, if all I need is a new master cylinder to finish the car, i can justify the expense.

I like the way you think. ( leave it to Texan )

Hey, you know if "Mark's Rebuilders" is still around in Keller?

I was a tech for him 'bout 17 years ago. He had some LBC stuff laying around but I don't remeber what. He was/is more of a VW guy.

 

[JPSmit]

can you get the seals that size? is there a way to order them by size rather than model?

 

[Guest]

can you get the seals that size? is there a way to order them by size rather than model?

Yes, some manufactures offer just the seals. We use to have a bin with all of the different sizes in it. You WON'T get this at Autozone or Advance,however ; the guy that works in the commecial dept might be able to find them if he knows his stuff. I know of two guys here (town) that can.

Pistons are avaible as well (kits for other makes) but you're on your own for matching things up for liability reasons.

 

[jvandyke]

I think you need "correct" seals though. I found this out the hard way as well, any old 3/4" cup seal won't cut it, it has to have the correct "skirting". I documented it here a while back. I imagine that to be true for 7/8" also. If you have the tools and ability and time to mod a 3/4" into something else, I'm jealous. I bought a decent 7/8" rebuildable for $25 and went on to something else.

Here's a picture from that other thread

 

[tdskip]

Well I'm glad I asked;

Are you folks saing that #2 180-970 $12.55 REPAIR KIT, clutch & brake
from Moss won't work properly?

 

[jvandyke]

180-970 is for a 948 so I think it's a 7/8" bore for front drum cars, then the 1098 went to 3/4" for a few years, front disc, then to the dual master system starting with 1275? I don't know anymore. The kits from Moss or VB should come with the proper diameter and "skirt". But "generic" cup seals may not work. They may have the correct diameter but not "depth", they maybe intended for wheel cylinders or such, not the MC. There's a small hole above the bore and it must be revealed/covered at the right time and this seems to be where the "skirt" comes into effect. Hey, I don't know, I'm a noob. I'd definitely get the kit intended for your specific MC.

Here's my saga
https://www.britishcarforum.com/bcforum/ubbthreads.php/topics/518691/3

Using a 7/8" bore (like for a drum brake BE) in a disc brake 1098 (mine) works but changes the pedal feel and such a bit, working fine for me, much better than a $200 resleeve, IMHO. Replacement or decent rebuildable 7/8" bore dual bore common reservoir masters like on a BE and later cars are plentiful, 3/4" bore ones like needed are non existent.

 

[Guest]

I think you need "correct" seals though. I found this out the hard way as well, any old 3/4" cup seal won't cut it, it has to have the correct "skirting". I documented it here a while back. I imagine that to be true for 7/8" also. If you have the tools and ability and time to mod a 3/4" into something else, I'm jealous. I bought a decent 7/8" rebuildable for $25 and went on to something else.

Here's a picture from that other thread

Just wondering, did you test it out or didn't proceed because of the difference?

 

[jvandyke]

I tested. And got the "burp" as in that thread linked in earlier post. But soon after determined that master was trash (pitted bore) and then got a 7/8" bore one, rebuilt with kit and have not had to mess with since.

I thought 50 cents and 5 minutes (at local parts house) was better than $13 and several days......wrong. Generic seals are not direct swap into a master was my conclusion.

More info on pushrod differences and all that, good history of it.
https://www.brakecylinder.com/spridgetbrakes.htm

 

[Guest]

Didn't checkthe link first, thanks.

Some m/c's do that, (GM if I remeber correctly) but right is right. If it aint supposed to then I wouldn't use it either.

Seems a shame though HAVING to go throw a LBC parts distributor.

 

[JPSmit]

Well I'm glad I asked;

Are you folks saing that #2 180-970 $12.55 REPAIR KIT, clutch & brake
from Moss won't work properly?

It's always worth the repair kit first as the cost differential between repairing and buying new is so large. I had no problem with my Brake MC and my slave cylinder with the rebuild kits, but the Clutch was too pitted so I bought a new one.

The "won't work properly" applies to the pitting of the Cylinder and not the quality of the kit

 

[nomad]

I've had both the 7/8 and 3/4 on disc front brake cars and while the 7/8 will work I believe you will appreciate the better pedal feel of the 3/4 if you can save it. They are like hens teeth so if you don't use it pass it on to someone who will. 3/4 that is.
KA.

 

[jvandyke]

I've had both the 7/8 and 3/4 on disc front brake cars and while the 7/8 will work I believe you will appreciate the better pedal feel of the 3/4 if you can save it. They are like hens teeth so if you don't use it pass it on to someone who will. 3/4 that is.
KA.

Agreed although any MC can be made to any bore so if you really want a 3/4 you can sleeve a 7/8" down to 3/4", those guys at the above posted link will do it. My 3/4" is in the pile of bits now. I'm happy enough with the 7/8" and honestly don't notice much difference. I expected some weirdness on the clutch side but it seems the same to me. When the MC needs work again I'll probably send the 3/4" in to be sleeved but remain 3/4".

 

[tony barnhill]

Has anybody called Moss to see if they know about the problem? & what their solution is?

 

[tdskip]

Thanks guys - I just ordered the Moss kit and will let you know how it works out.

I appreciate the help.

 

[jvandyke]

Has anybody called Moss to see if they know about the problem? & what their solution is?

I don't think we identified any problem with a Moss product. Just a problem trying to use "generic" off the shelf seals.