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Posted: 14 Oct 2006 05:53 pm
by sven360
Nice one Carl- you've taken the heat off me-thought the Mac would shun me if his R+D work went to waste
Just back from another callout so the lil' 360 lying at work all alone again.
Posted: 21 Oct 2006 05:51 pm
by Carl
Done about 100 miles now with the new gasket and there's no signs of any leakage
Update.
Posted: 25 Oct 2006 02:08 pm
by mac
Looking good for the gasket material - I shall almost certainly go for the 1.2mm. Unless there is a disaster in the next week or so I shall start qty. discount negotiations with the supplier.
I have found a supplier of the correctly sized drain and filler plug washers and intend to supply two with each gasket (should be about 50p). I have ordered a small number of both oval section (sump plug type) and flat section to have a play. I intend to go for copper not alloy (as even volvo seem to be going these days).
I have converted Varts old scrap diff casing into a sizing jig to ensure each gasket will fit before sending out (always a problem to be exact when each gasket will be hand cut).
The final pic shows the end result with the cover fitted with stainless steel capscrews and washers - I shall be able to supply a set of these as an option (depending on the quantity I buy a set of 10 should be around £1.00 or so.
Mac.
Posted: 25 Oct 2006 03:38 pm
by Ronnie
Nice work, Mac - your attention to detail is as awesome as ever

Posted: 25 Oct 2006 05:56 pm
by Chris_C
Pimp! Only thing I'd be worried about is the socket head cap screws doing what they do best, and turning into circle head cap screws (as even the Torx ones on my 1.7 timing belt decided to do...
Would they not do this being stainless, or do they all start out stainless anyway?
Posted: 26 Oct 2006 08:29 am
by mac
Mornin' Chris,
The standard fittings are 8mm inhex cap screws and are not s/s. Many of those on Varts old diff were basically F####D.
Using s/s and not overtightening avoids the inround syndrome - hence my intention to offer a s/s set as an option. You could of course use 8mm X 12mm hex head set screws but they are a lot easier to overtorque than inhex ones. It seems a major problem is distortion of the cover plate and I would tend to stick with OE but simply upgrade the material.
Mac.
Posted: 26 Oct 2006 08:35 am
by antiekeradio
s/s = stainless steel, I presume?
Posted: 26 Oct 2006 08:38 am
by mac
Correct Wouter.
Posted: 26 Oct 2006 09:00 am
by pettaw
Mac just a quickie thing, great work by the way. My rear cover plate on the red car leaks, but I can see its been bent, presumably by a spanner monkey jacking the back of the car on the rear diff
By anyway, to my question/point. I'm not altogether sure that they used oval section copper washers on 300s, either on the sump or the g/boxes and diffs. If they work better I'm quite happy to try, but I've always used the OE flat section ones.
Posted: 26 Oct 2006 10:21 am
by mac
Mornin' Andy,
I think you're right about the diff leak - I've seen similar several times - trolly jack under diff casing and the 'ears' on the jack pad catch the lip of the cover - bingo one leak and a f****d cover!. If you're lucky a little reshaping may well restore things.
As to the washers - quite correct the OE ones are flat section and that would be my prefered choice also. My only thoughts on using oval section are that in some applications I've found they seal a little better if the sealing face on the case/sump is not perfect. On a 20yr.old diff case with a bit of pitting on the alloy and a bit of rust on the cover they might compress and seal a little better. While I'm sourcing a supply of washers anyway I thought I'd have a play with different types - may as well look at all the options. (but I absolutely agree with what you have said several times before - generally OE stuff is the best for the job)
One option I won't be looking at is the use of aluminium washers that seem in vogue these days. Both the filler plug and drain plug seals on Varts old diff were alloy and had corroded almost through. I'v also recently seen cases where alloy washers had been used on brake pipes - and had rotted to the point of leaking !!!
Mac.
Posted: 26 Oct 2006 10:38 am
by pettaw
mac wrote:Both the filler plug and drain plug seals on Varts old diff were alloy and had corroded almost through. I'v also recently seen cases where alloy washers had been used on brake pipes - and had rotted to the point of leaking !!!
Mac.
Nice
Thanks for the info Mac.
Posted: 26 Oct 2006 03:42 pm
by Chris_C
And thanks for the confirmation on the screws Mac, sounds all good.
Posted: 10 Nov 2006 08:48 pm
by Fuse
I made a diff gasket too, it was supposed to be a test piece, but it came out kinda good so I think I'm going to try it.. It's not as nearly as smooth on the edges as the ones Mac has made but it'll do for me, dimensions are correct and as long as it holds the oil in I'm fine.
Mac huge thanks giving the dimensions! Very usefull.
Making model from cardboard
http://koti.mbnet.fi/mtn/images/autot/G ... G_2150.JPG
http://koti.mbnet.fi/mtn/images/autot/G ... G_2149.JPG
Gasket it self
http://koti.mbnet.fi/mtn/images/autot/G ... G_2151.JPG
http://koti.mbnet.fi/mtn/images/autot/G ... G_2155.JPG
http://koti.mbnet.fi/mtn/images/autot/G ... G_2156.JPG
http://koti.mbnet.fi/mtn/images/autot/G ... G_2161.JPG
http://koti.mbnet.fi/mtn/images/autot/G ... G_2162.JPG
http://koti.mbnet.fi/mtn/images/autot/G ... G_2167.JPG
Now I just need a better back plate than my current one is but luckily Aukki is bringing one over at the next week.
Btw. the model pic of the gasket is over the size of the A4. So if you print it with A4 printer without taking out the unnecessary white area, most programs will scale the pic and then the gasket will be wrong size. So it's better to cut out the unnecessary white areas so the pic will fit on A4 as a whole.

Posted: 11 Nov 2006 11:44 am
by mac
Nice work Fuse - I hope my drawing was accurate!!! (do check your gasket against your new cover before pulling everything apart - if you have scaled to the dimensions given you should be fine).
Mac.
Posted: 11 Nov 2006 10:13 pm
by classicswede
Nice work Mac - I'll be putting my name down for a kit when you are ready with them.