Hi,

I'm on the process of recovering the sierra donor parts. I've now reached the part where I get the diff housing to sandblasting to be powder coated next, but I haven't solve the mystery of disassembling it...
Has anyone ever disassembled one or have done it recently? I could use some lights on this matter! Pics would be an excellent bonus...

Thanks

[Edited on 1/5/11 by Tilo]

Unless you know there is something wrong with it, leave it alone bar a lick of paint and an oil top up.

no, i wouldn't. i wouldn't take it apart myself, and i wouldn't sandblast it either. imagine the bits of grit that might get trapped in there!
no, soda blast the outside, and paint, leave the insides well alone

They come apart quite easily to a point if you have a tool to undo the 2 castellated nuts on either side. However to reset the pinon after fitting new bearings requires a load of special 'Ford' tools which you cant get hold of.

Leave it alone and just give it a coat of paint. Wash it with gunk to get rid of the oil and muck off it first.

Well, getting access to Ford tools is no problem to me, unless they're very, very old...

I've already taken off the back plate, drained the oil and gave it a clean with air gun and solvent to have a better look. Tomorrow I'll have a look at the shop for the special tool for the side nuts. What's the next step, after removing the side nuts?

If you look on my website you'll find this:

http://gtslocost.locostsites.co.uk/diffoverhaul.pdf

Which is the ford manual that details the full procedure...

If you need them, I have a set of new pinion bearings and crush spacer in the garage which are surplus.

Awesome tutorial! But, do I really have to go through all that to get the housing free for sand blasting? From what I saw, the crown wheel comes off right after I remove the side nuts and the pinion after the flange nut. Case is now empty, no need to go further, or do I?

i don't want to be rude, but if you don't know how to take it apart, how are you going to put it together again, properly, and have it work without chewing itself up?

and remember, sand blasting will leave hidden grit in there. bad idea

[Edited on 1/5/11 by blakep82]

The fact that I've never done it doesn't mean that I am not capable of. That pretty much applies to the whole build. Never built one before and, well, I got so far...

very true.
well, good luck

Check on the driveshafts topic... It totally worth it! They're a beauty...

http://www.locostbuilders.co.uk/viewthread.php?tid=153981&page=1#pid1307014

quote:

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Originally posted by blakep82
very true.
well, good luck

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The castelated side nuts will be tough to remove, wire brush around and soak where the hidden treads are in decent penetrating oil 24 hours before you try undoing as the ali of the nut will have corroded to the casing above the rubber sealing ring.

On mine I also had to apply a little heat to the casing to get it to move.

To remove the pinion you need a very long socket, I cannot remember the size but I got a suitable short air socket from halfords for £5 and cut the square drive end off and extended with a couple of inches of 2" scaffold tube.

I was able to twiddle off the castelated nuts with a bit of bar across the lugs, do not hit them or they will drop off.

Good luck

Regards Mark

Its not taking it apart thats the hard bit, its putting it back together properly afterwards as you need the range of special measuring tools to set the pinion height again. Which will need doing irrespective of if you change the pinion bearings or not. Just removing and replacing the crown wheel is easy.

But you would be a fool not to replace all the bearings while its totally stripped.

You asked for advice, my personal advice would be to leave it intact, clean the outside and paint it. Not sure what the heat from powder coating would do to the casing either. I would put money on it moving a bit somewhere.

If you want to do it, go for it, you might be lucky and it wont whine or clonk when you get it back together...

So, took a look at the shop tools board and can get hold to most of the tools needed for the job... The case is cast aluminum, don't think the 200ºC of the powder coating are enough to distort it. The finish and appearance of a powder coated piece is completely different than just drop a bucket of paint on it!

A lot of effort for something you'll never see....

You'll be suprised how much a casting will move when its heated.

Up to you

Just read through this thread with interest, I remember Dave (Flak Monkey) posting the diff stripdown - sounds 'diff'icult to say the least.

I have one thing to add - you seem to have been given quite a clear message - ignore it and it may be ok, but if it fails, there's always This.....

Good Luck!