Changing oil on EDC III shocks

[shogun]

This we did as an experiment on an E32 750iL Alpina B12. In general it is said the shocks are non servicable, but it is possible, we already had some apart from the rear and replaced some o-rings. Front shocks are a bit more difficult, but this time we welded 2 washers to the top plate and then we could lift the top seal out without damaged it like this
http://8810.teacup.com/750hiline/img/bbs/0001321M.jpg
http://8810.teacup.com/750hiline/img/bbs/0001321_2M.jpg
http://8810.teacup.com/750hiline/img/bbs/0001321_3M.jpg
Then we attached a slide hammer and pulled it out. Actually it was a dent puller as we borrowed it from a friendly paint shop which allowed us to use their shop, looks like this
http://toolmonger.com/wp-content/upl...ntpullerlj.jpg
In case someone is wondering why the wheel is still on (or again on), that we did re-attach to have the shock nicely secured and have power when using the slide hammer.

The oil inside was quite dirty from >20 year or working and tiny material from the seals was found when we filtered it and it looked similar like Pentosin. We measured the drained oil and replaced it with the same volume of about 400 ml. We used oil for motorbike shock absorbers and so far so good. Were also thinking about forklift oil
From what I have got as info from someone who is also studying this, the original fluid/oil is

ESSO EGL 45 374 or DEA 5045 f (the f stands in a circle O)
volume/quatity:
The piston must be in oil up to the upper rim of the cylinder (a small amount of oil must flow into the spare/reserve area between inner and outer cylinder when closing the cylinder, but the spare area should not be filled more than 2/3 filling height. Pictures or drawings I unfortunately cannot send you. The sealing cap of the front shock probably must be destroyed, for example by heating, the inner gaskets melt. But you must keep them, as most of them you have to re-use.In case you find a good way to add compressed air, please let me know., thank you. 3 Bar

[gregeast]

Hi Shogun, just curious how these shocks are working after ~8 months?

[shogun]

Works fine, we did it meanwhile on 3 more E32 750iL Alpina B12.
We also found out that a slidehammer/dent puller is not absolutely necessary to do the job.

[gregeast]

Excellent. Did you only change the oil or did you replace seals as well?

Assuming only oil, was that enough to improve the damping?

[shogun]

We only changed the oil and that was enough to improve the damping.

[gregeast]

Simple enough then. My struts seem ok in compression but are under damped in rebound, so I'll probably give this a try sometime.

Thanks as always, hope you had a great trip.

[gregeast]

Sorry to resurrect this 4 year old thread, but do you know what viscosity motorcycle fork oil you used Shogun?

[shogun]

My wrenching buddy has a list on his Japanese website, click in the index on EDC http://e32b12.blogspot.jp/ there are different brands listed like from Yamaha and the viscosity
language can be changed to English on the left side. And below these are for comparison the data of Pentosin CHF 7.1 and 11S.

In an old thread from the E34M5 forum in Germany I once posted this info, which I got from someone who researched a lot
ESSO EGL 45 374 or DEA 5045 f ( f in is in a circle) , 11 years ago http://www.e34m5.de/board/showthread...fer-Reparatur&
But no one can find these oils, so we too shock oil

more pics under struts http://e32b12.blogspot.jp/search/label/Strut

https://www.bimmerforums.com/forum/s...-refurb-shogun

interesting youtubes for RC track oils, just for info:
How to choose shock oil and oil weights https://www.youtube.com/watch?v=dRxIs1q9tKE
Shock oils https://www.youtube.com/watch?v=Z16X-lKOMhw