77-78 Rear Wheel Cylinder Brake Rebuilds

[Zed Head]

OReilly Auto has them for about $22.  Just realized that there are zero Oreilly's in the Philadelphia area.  Must be some mafia thing.  Weird.  But, the local auto mafia, whoever they are (probably the same crew that sells beer by the case from open warehouses), probably has some.  They're not that NLA yet, I think.

https://www.oreillyauto.com/shop/b/brake-systems-16456/brake-hydraulics-16513/wheel-cylinder-11318/5020ef8206ed/1978/nissan/280z?q=brake+cylinder

[Captain Obvious]

Yes, Granny... Sorry, I was talking to you. I saw the feet and got all confused. Thanks for the info. I suspect the cast iron units are older and have been knocked around. I think the aluminum casting versions are newer. In theory, form, fit, and function should all be the same. In theory.

And Zed, I've actually got SIX cylinders and five of them leak. One good one on the car, and one leaker, and then four old ones hoarded away in a box on the shelf. I have a bunch of old dead seals there too, but the old dead ones are even worse than what's on my car. I looked everything over carefully trying to come up with a combination I could just run for a couple days while waiting for new replacements, but to no avail.

However......

Because I hate to lose (well, that and some OCD), I figured I had extra pistons, so I chucked up a piston on the lathe and started cutting:

First one turned out OK, so I did a second. Original pistons and seals on the left, modified on the right with the smaller hole seals:

Put seals on the pistons, and they look great. Looks just like the one that Granny got:

They slid nice and snug into the wheel cylinder, and while this is a temporary fix, I'm hoping it holds until new replacements get here.

Someone may ask why it's just a temporary solution? Because during the machining, it was clear that the piston was case hardened, and I cut through the hardened skin down into the softer interior. If I were to heat treat the modified pistons, they could become a permanent solution, but I could probably purchase a lifetime supply of wheel cylinders for the cost of that heat treating.  

[grannyknot]

We do get a couple of months of bare foot weather each year  Nice fix, I would be temped to leave the repaired wheel cyl. in just to see how long they lasted, I'm willing to bet you would get years out of them.

[Captain Obvious]

I put that wheel cylinder back together with my modified pistons and made it around the block, but I really have no idea about the longevity. I do know just from messing with them that the pistons really should be hardened, even if it's just a case hardening like the original.

I know this because I had put a seal on the first piston just as a trial test fit, but when I took it back off, I could see the scrape marks from the tool I used to pry the seal off. With the machining modifications, I can now get the seal ON without tools, but I can't get it off by hand. Tools area required. The original hardened surface was hard enough to prevent those marks, but the softer underbelly beneath the hardening is not. So they may be fine until it comes time to replace the seals, and then I'm gonna scratch them up getting the seals off.

So I'm going to order two new cylinders from the crapshoot that is rockauto, but the basic underlying mystery still remains...

"The rebuild kits they sell do not fit the wheel cylinders they sell. WTF?"

So a little more about the cast iron wheel cylinder you got. Guessing by the shape of the dust boot and the piston seal, it looks like the small seal design. I have a couple rebuild kits here that have boots and seals that look exactly like that. What brand cylinder were you ordering when you got that one? Of course, I have no idea if I would get the same version though. Even you didn't get two of the same when you ordered two of them!

[grannyknot]

I ordered 2 Raybestos p/n RAY WC37405,

[Captain Obvious]

Thanks bud. Appreciate the help.

I did some digging around and I've turned up a couple of the cast iron versions. Now I have to wait a couple days while paypal uses my money for free. I didn't notice, but my acct had gone too low to pay for the wheel cylinders. As soon as they are done fondling my dollars, I'll buy some cylinders. I'm hoping the cast iron versions used the smaller hole seals. So in the event that I have to go through this again, I'll have the correct rebuild parts next time.

@madkaw, Did your old ones turn up? Or did they leave the premises?

[Zed Head]

This might be of interest.  Not much but more than just two hard to find years in one model.

[Captain Obvious]

Update... I purchased a couple wheel cylinders off ebay, and at this time I've got a Tokico (which uses an aluminum body) and a Wagner (which uses a cast iron body). Interesting to note, however that both of these cylinders were in Wagner boxes, even though one of them is a private labeled Tokico.

Here's a pic of the two with one of the pistons pulled out of each:

And looking closely at the seals they used, both of these cylinders could easily be rebuilt by the plethora of rebuild kits available everywhere. I didn't pull the seals off the pistons because of the damage risk, but here's a close-up where you can see how deep the seal goes onto the piston. They clearly use the smaller holed seals. This is the Wagner branded piston:

And this is the piston from the Tokico branded piston. Note the dried up crusty grease from sitting on someone shelf for decades:

So... As far as the whole rebuilding process, it's starting to look like many of the wheel cylinders out there can easily be rebuilt with the ubiquitous rebuild kits, and so far the only ones that CAN'T are the ones that are (and were) on my car. I don't know who the manufacturer is of these cylinders with the "L" logo, but they are the only ones I've found so far that will not work with the rebuild kits.

If you want to be able to rebuild your cylinders in the future, avoid these made in China versions:

[Zed Head]

So this has no value to you now?  I've been saving it.

Just curious - where were those parts made.  Should be shown on the box. 

 

[Captain Obvious]

Where were they made? Interesting story...

The labeling on the one box which contained the Tokico cylinder looks like this. Has made in Japan on it in a couple locations. On both the UPC label with the Wagner P/N:


And another sticker elsewhere on the box:

The OTHER cylinder... Made by Wagner in a Wagner box. Clearly has "Wagner U.S.A." cast into the cylinder body:

And interestingly, there is no "made in Japan" sticker on the back of the box, and the UPC label looks like this:

I you look at that UPC sticker at the correct angle under the correct light, you can see that it says "Japan" under the black marker. I don't know who obscured the label, or how many years ago, but it's certainly interesting.

[Captain Obvious]

And my old "L" logo cylinders... I bought that pair from Rockauto some time ago, and they were AUTOSPECIALTY / KELSEY-HAYES W51104 and while there are no markings on the cylinders themselves, the box said "Made in China".

Oh, and forgot... The other side of the Tokico has "Japan" cast into it.

[Zed Head]

I wonder if the Wagner cylinder is a reman, so they covered the "Made in" mark.  I'm fairly certain that my rusty piston is original Nissan.  So, in 1978, probably made in Japan.

Seems odd that Wagner made molds and had a process for casting Nissan replacements, for a fairly limited number of vehicles.  Things were different back then, I guess.