Rear upright assembly
 

Aaaarrrggghhhh!!!!!

Trying to find out how to assemble my rear hubs/uprights and finding nadda!

I've got a set of off-verticle rear uprights (compatible with both drum and disc) and rear hubs off a disc-braked sierra.

My question is this: How should the uprights be alligned (leaning forwards or backwards?) and where should the caliper mountings be pointing on the hub once attatched?

I've spent an hour searching through posts and using the search fuction and found almost nought! Did find one brief post saying that the uprights should lean back on a drum brake system, but thats it!

Am I being dense? Not looking in the right place? Any help to aleviate my frustration would be greatly appreciated!

Ive got a set too at 45 degrees i got off Talon, ive been meaning to look into which way the slope goes as well!? :confused:

Im glad you've asked :D

Will

Put the uprights side by side and hope I've supplied you two that are pair, ie they face away from each! The caliper goes at 10:30 if seen from the drivers/off side and at 2:30 when seen from the passenger/near side.

Bought so many parts at the same time I completely forgot I bought the uprights direct from the manufacturer!

Just had a quick look Talon (yes, they are a pair!), I take it that means the calipers are towards the rear and up, requiring the top of the uprights are closer to the front.

That sound about right?

Is that am or pm phil:confused: :p

bob

That would depend when you start the job and if you stop for lunch or dinner.

I thought it was simply the old 48hr clock? At least that's how long any "simple" job seems to take...

Oscar,
I have the same uprights as you, but with drum brakes. I guess for disc brakes, they should be the other way around.
For drums : the two top holes of RU8 are towards the front of the car if it makes sense. On this picture: the left side of my chassis (driver side for me but passenger side for you :) )

Attachment 1582

Hope this will help.

I'm thinking, what effect would such orientation have when bleeding the cylinders? A pocket of air against the piston might be a nightmare to get out.

Now I'm even more confused! :confused:

Two top holes towards the front is how i'd guessed the uprights would be for discs. Need someone who's built a disc rear with these. Maybe Talon will be able set this to rest...

The bleeder is of course on top position on the wheel cylinder and is at the highest point of it. So it is theoretically even easier to bleed than a flat mounted wheel cylinder.

http://www.haynes.co.uk/forums/attac...1&d=1357384227

Oscar, Phil (Talon) told in the first place to put them the other way around for drum brake, but if I do so, the handbrake cable sleeve is too short to go to the back of the drum flange. So I had to put them this way which I thought was the normal way for drums. But perhaps it isn't, and the disc set-up is "top holes towards the front" as well. Sorry to get you even more confused :o

[quote=voucht;87700]The bleeder is of course on top position on the wheel cylinder and is at the highest point of it. So it is theoretically even easier to bleed than a flat mounted wheel cylinder.

Alga is corrrect on this. Both of the drillings into the brake slave are angled towards the center of the unit. If the piston is not pushed fully back when the brakes are bleed the piston looking skyward will have air trapped under it.

Bob

Bob, I don't know if you had a look at the picture I put a link to, but to me it looks pretty obvious that the air can only go up to the bleeder, even more if as you say, "the drillings into the brake slave are angled towards the center of the unit", no? With this set-up, "the centre of the unit" is still lower than the bleeder and the bleeder seat. Or I don't understand anything any more...
Well, I haven't tried to bleed the brake so far, so I can't say for sure, but I don't see where a bubble can be trapped inside the cylinder with this set-up :confused:

Yes I did see the link. Think of it like this, the bleed screw and the feed pipe are both channeled to the center of the cylinder, the bleeder can only let air out up to and below that point. Once the brake shoes and drums are on the upper piston will push out and that will be the pocket of air that that cannot be bled off as the bleed nipple is below the pocket of air.. I am crap at drawings so I cant do you a diagram:o .

Bob

OK ok, I totally get your point now, sorry I didn't get it the first time :)
Yes you are right, this might be a problem.

But note that on the Sierra, wheel cylinders are not flat either, but they lean backward too, not as much as these 30°, but they do (I would say about 15°).

The other point is, when you bleed, the pistons don't move and stay in the "closed" position (if I can say so). So if in this position, the bottom of the top piston is lower than the bleeder hole (depend on the piston's thickness, I think it is but it has to be checked), the problem you describe should not occur.

Or at least that is my hope :eek:

We'll see when I bleed my brakes :p

It might be best to centralise and clamp both pistons shut to bleed the rears then fit the shoes+drums after. Just thoughts.

Bob

Hang on, am I the only person on here using discs?!?! :eek:

Just had a look through my dismanling photos and can say for certain that the rear disc calipers sit practically on top of the disc, slightly back.

This leads me to conclude that the top holes of the rear uprights must be forwards! :cool:

Anyone disagree?

Now looked at Janne's and superseven's builds, both use discs and have the calipers mounted on the rear.

This talleys with what Talon has said and indicates the top holes are indeed forwards. This also keeps the bleed tube at the top.

Sierra rear calipers original position:


And some MK Indy caliper position (upside down) - similar to Haynes Roadster I think:



Hope this will be helpful for you...

Thats looks almost exactly as I thought. Cheers Loony

And yes, the mk Indy ones are very similair to the sierra ones, right down to the Ford marking!

Haynes Roadster upright is similar to MK Indy... not the calipers ;)

Important question - I didn't find answer.
Rear hub mounting plate is rotated 30 degrees... so the one hole is on top... which hole is this ?
Is it the the top right one (in book drawing - 90mm spacing) ?

I can't find OD127 tube, so I "design" my own upright - something like MK Indy..

You could just ask the people who make Roadster parts on here if they sell the 5" by 10g tube as a part......I have around 40 pairs currently in stock.

I know that some people offer them even at ebay, but I don't think it's cost effective as I live in Poland ;)

But - if I got this tube, I still have to know how I should position RU8...

I found this (by Spikehaus):

but I can't definitely say how it is positioned.

Haven'y got the book to hand, but I think you mean the hexagonal plate visible on top in your photo?

If so, the holes are central around the 5" tube, and you make one the reverse of the other. The right hole topmost on one, left topmost on the other.

From looking atmy calpiers, I believe the best way for the bleed valve and handbrake cable is for the topmost hole to be the one that is closer to the front. i.e left hand upright has left hole topmost.

OK - everything is clear now...
I stick to drum-brakes RU8 drawing... and forgot about one drawing in "the book" ;)

So - the top holes are this at 94mm spacing... left (left upright) or right (right upright)

Sorry for my mix-up...

Easy enough to get confused.
The plate is the same whatever setup your using, because the hubs are the same. The only thing that changes is how you have it angled. And the angle is up to how you can make it all fit!

Glad to have helped, it's about time I gave a bit back to this forum! :cool: