15 - Differential strip.

[Robdavies]

Afternoon to you all,
I have a question for anyone who has stripped down their differential on their 15.
I have my differential on the bench today, strangely seems to be full of dead bees !
Anyway I've removed the twelve bolts on the crown wheel side and gently tapped it loose enough to take the brass shim/seals out, 4 top+btm.
I've also removed the U shaped retaining clip next to the bearing on the other side.
Do I need to remove the very large nut, a whisker shy of 2+1/4" to open the case or does it come off attached ?
It must be a big old box spanner to do it, my largest socket is a 1+1/8 bsw and it's much bigger.
Your thoughts would be appreciated.
Rob.

[qantasqf1]

Rob, the good news is that this nut doesn’t need to be undone to remove the diff., but the bad news is that the offside bearing must be removed by a special extractor to lift the diff out. This step allows the complete diff. assy plus the 12 bolt retaining plate to be tilted slightly to remove it from the case. The large nut can then be undone on the bench.
I should say that the manual here is damnably vague, but it looks to me that it may be possible to remove the offside bearing housing, (=the bearing sleeve) which, according to the illustration, maybe afford enough space to remove the diff. In either event an extractor is needed.
May I ask why you’re removing the diff? The reason I ask is that unless there’s a very good reason it’s far better to leave it well alone. If it’s solely to clean it up and ‘de-bee’ it then I would definitely not strip it. Just a suggestion.
Steve

[Robdavies]

Good morning,
Thank you for taking the time to give your good advice it certainly helps.
I was just going to peep through the filler plate and flush out but on seeing the crown wheel I thought I'd better take a closer look.
The outer edges of the teeth seem to be in fairly good condition, but the working face of the teeth all have quite serious pitting and there is some gold dust evident too so I thought whilst on the bench I'd crack it open and see what's what.
In turning it by hand there is a small amount of play / delay prehaps a 1/4 of an inch when the drive shaft is turned but I'm not sure if that is normal.
Only about a half cup of very dirty oil came out but some had dripped and leaked whilst in store.
That said the whole car has been through the wars and some scary botches found whilst restoring it so I imagine the differential may have been similarly ignored. I have a complete rear axel in bits but I've not seen inside to check it's condition yet.
The size of the nut is a worry, my biggest bsw socket is much too small at 1-1/8 .
It seems to be about 56.34mm so I wondered if I could get one a 57mm socket might do the job.
I don't suppose you know the correct bsw size do you, it sure is a big monkey.
Anyway thank you very much indeed for your time, it is most appreciated.
Regards Rob.

[qantasqf1]

Sorry, Rob. Can’t help you wth the size of the nut. The backlash is normal.

[qantasqf1]

Rob, here are the illustrations. If you need more advice email me, but it can be seen that the sleeve is threaded for the extractor.

[Robdavies]

Hello,
This is a tricky one, I wrote the following after studying the pictures and the drawings in the parts catalogue which seems to show a retaining sleave inside the bearing, but on studying the profile drawing of area it seems that the bearing sits directly onto the internals so how the hell does the extactor do its job ? Does it pull it out or push it in to free the gears inside.
So I'm pretty sure all the following is wrong but I'll leave it as I'm too worn out after a fruitless day in the workshop.

Thanks very much for the photos, having studied the extractor in the photo, which I must admit had me guessing for a while, I think it is just a nice factory version of a center pull extractor. Correct me if I am wrong but it seems that you screw the large bowl into the case then wind the center pull anti clockwise to pull off the retainer that has the spring clip groove in it, I assume it is just a push fit on to the through shaft. I cant see any other way it could be fitted, based on the parts shown in the parts catalogue. It can't pull the bearing as there is nothing for it to attach it to.
Have you actually done this operation ?
By the way, it's intresting to see the photos, I guess they must be from a workshop manual. Is it specifically for the Daimler 15 ?
Is it avaliable anywhere to copy/download /plaguerise/ buy/ rent/ etc ?
Yours Rob.

[qantasqf1]

The extractor is made up of 2 parts, an inner and an outer detail. The outer detail is threaded externally to thread into the sleeve as shown in the close-up illustration - it doesn’t screw into the aluminium casing! - while the inner detail butts up against the bearing. When the operator turns the inner detail clockwise it withdraws the sleeve, leaving the bearing in place. At least, that’s how it looks to me. The operation itself is simple, but the big problem is finding an extractor. Maybe others on the Forum have encountered this problem or know someone who has. Without the extractor this job would be extremely difficult, if not impossible. The part number for the puller is MT86. I ran a search on this but drew a blank.
The illustrations come from Newnes Motor Engineering Vol 4 published c1938. Covers loads of cars, not just Daimler.

[Robdavies]

Hello again.
Bingo now I get it, yes the sleeve is the trick but oh what a tricky trick !
I've made a few simple service tools in the past but this one would be a Doozy !
At least with the part number and an idea of what it actually does I feel better equipped.
Anyway some light has been shed in the darkness.
I think I'll try removing the large nut as that at least should be relatively easy to gain access to the inside for cleaning out the sediment.
It should mean the side cover can be removed without disturbing too much of the gubbins.
Funnily enough I recently bought the wonderful series of Newens books you mention but I've only read the first volume so far covering engines.
I'll let you know if anything interesting occurs,
Thanks again Rob.

[Sydsmith]

Rob, when it comes to a diff, if it ain't broke don't try and fix it, rinse it out well fill with the correct oil and leave well alone until it tells you otherwise. Been lots of discussions on here about which oil to use with the diff you have, put in the wrong oil and it will destroy the bronze. Syd

[Robdavies]

Good evening,
I must admit it is very tempting, it's not actually broken, but it does have a lot of sediment, metal flakes and crud in it.
That said, it does work, I don't have the right extractor or even a large enough socket so prehaps it is the one occasion when I should just do what I can and not think too much.
I don't like quitting, but when the job list says - fix everything, there are bound to be a few tough nuts that are harder to crack.
Cheers.