Rear axle seal installation, wheel cylinders, etc

[tiagosantos]

Howdy

Long story, but I had to flip my backing plates around on the axle tubes. I took the opportunity to replace the seals and gaskets on the bearing retainer (one side was damaged anyway).

First question: on the first bearing retainer, the new seal went in pretty easily - a press fit, but went in with more or less gentle taps with a rubber mallet. The other side, not so much. Tried pressing it in with a big parallel and some clamps and it just wouldn't go in straight. Tapping it with the mallet didn't help much, eventually I just mangled the seal and had to give up.

I'm buying another seal and I'll try again, but anyone have any good tips? Also, any difference between the 5 dollar mexican seals and the $16 SKF ones?

Secondly, I'm also replacing the wheel cylinders and brake hardware. I have two brand new pairs of wheel cylinders - one is TRW, the other is a generic "OE brand". The castings look similar, but the main difference I noticed was the slot where the brake shoe goes - the TRW cylinders have a very wide slot, whereas the generic ones have a slot that closely fits the shoe. The TRW slot is about twice as wide as the shoe. I also noticed some of the angled adjusters have a wide slot, others have a thin slot. What's the deal here? Seems like the thinner slots would avoid problems with the shoe moving around on the slot. Does it matter?

And finally - the "stock" brake setup uses two springs to retract the shoes. I've seen some people use 3 springs, one on the adjuster side and two on the wheel cylinder side. I guess it'll help prevent dragging shoes, but I did see some damage to the wheel cylinder, which I think might have been caused by the extra spring. What do you guys think?

[SR Racing]

Either are fine. (slots and cylinders) Even with the small slots it won't hold the shoe in place any better. The original OE were pretty wide (cylinder and adjuster).

2 springs in total (1 top and 1 bottom, or left right) are all that is needed if everything is working right.

In regards to the seal and retainer.. Don't think I have seen that particular problem. You have to be carefull installing them and they are a "light" press fit, but they should go. We have some press fittings that fit the edge of the seal perfectly, so they always go in pretty easy.

[tiagosantos]

Thanks Jim. I've picked up a couple of new seals and will try again tonight.. I don't have a press, but I'll rig something up and keep the mallet away from this thing

[FV80]

If you have a vice and a *LARGE* socket, that should do the trick. I don't recall having any real issues putting in seals before, so this seems rare to me. (you might try some lube on the seal outer ring - maybe that will help? - but it will make it tougher to 'handle'). - BTW - don't forget to put LUBE (oil or grease) on the INNER lip before assembly. The quickest way to ruin a good new seal is to put NO lube on it and spin the shaft at speed!

As an aside, I would NOT recommend replacing the seals routinely (I don't even replace the orings unless they seem to need it). I think I've replaced a seal (that was leaking) only about twice in over 30 years of vee'ing. The seals are intended to last at least 10,000 miles - probably more like 40,000. How many years of racing does that come out to ?? .

Steve, FV80

[tiagosantos]

Thanks Steve

I replaced one side cause it was damaged and leaking, and since I had to rotate the backing plate 180deg on the other side as well*, I figured I might as well do it. If these work and don't leak, I'll hopefully never touch them again!

*bought the transaxle from someone else, the flange on the axle tube was the wrong way around for my car, so I loosened the boot clamp and rotated the whole assembly. Which meant the wheel cylinders were now pointing down instead of up, etc etc etc

[BLS]

Tiago, when I first read the description of your brake cyl, I though that might not be a good idea. Mine are on the top, as are most cars I have pictures of. However, I have pics of them on top, front, and back, everything except the bottom. I guess it's OK... I think it changes which shoe is the "lead" shoe, so if the shoes are different you would need to account for that. I think...

[tiagosantos]

Hey Barry,

I think the main reason they shouldn't be on the bottom is it makes it harder to bleed properly, as air tends to go up.. But yeah, they were on the top, since I had to rotate the axle tube, they moved to the bottom - so I'm rotating the backing plate to move them back to the top

Thanks again!