Page 1 of 2
Rear main seal
Posted: Fri Dec 25, 2015 10:18 pm
by SteveD
There seems to be three-four options available for the rms.
Local parts seller here in Oz has the oem black BMW seal for $44 and a black pattern version for $32..."TEFLON DESIGN, **Supplied with plastic seal protector /lip form"
Motobins has a black "latest BMW version" for around $28 and a brown one with "Improved sealing with 2 lips, traditional type with garter spring"...same price.
The oil pump o-ring is pretty much the same price @ $4.
Considering local verses international post will probably even out the cost b/w the two sources, what's the consensus amongst y'all of which rms to buy?
Also, is it worth buying a tool that helps with installation? They're $80 or so.
Re: Rear main seal
Posted: Sat Dec 26, 2015 1:09 am
by SteveD
We have an offer to borrow the installation tool. 
Are the 81-84 oil pump screws still philips head? Do they need replacing if removed? Can they be replaced with an allen head bolt?
Re: Rear main seal
Posted: Sat Dec 26, 2015 1:32 am
by ME 109
10mm hex head, Steve.
Allen head will be unsuitable I think, there's not enough clearance for a big bolt head.
Re: Rear main seal
Posted: Sat Jan 02, 2016 11:41 am
by richard t
SteveD wrote:We have an offer to borrow the installation tool.
Larry fix-it use to use a piece of 3 in pvc pipe
Are the 81-84 oil pump screws still philips head? Do they need replacing if removed? Can they be replaced with an allen head bolt?
Re: Rear main seal
Posted: Mon Jan 04, 2016 10:39 am
by Duane Ausherman
The RMS installation tool is certainly nice to have, especially in a shop where time is paid by the customer. However, I have installed quite a few of them without any tool. Gently and careful use of a light hammer is enough. Getting it started in is the challenge.
Re: Rear main seal
Posted: Mon Jan 04, 2016 6:18 pm
by SteveD
Duane Ausherman wrote: Getting it started in is the challenge.
Is leaving it in the freezer for a while worthwhile?
Re: Rear main seal
Posted: Mon Jan 04, 2016 7:15 pm
by Major Softie
SteveD wrote:Duane Ausherman wrote: Getting it started in is the challenge.
Is leaving it in the freezer for a while worthwhile?
I would guess that it would greatly increase the risk of damaging the lip of the seal.
Re: Rear main seal
Posted: Mon Jan 04, 2016 8:45 pm
by Rob
They used to boil them in oil!
Re: Rear main seal
Posted: Mon Jan 04, 2016 10:29 pm
by Duane Ausherman
I would prefer it to be warm, or hot, certainly not cold.
Re: Rear main seal
Posted: Tue Jan 05, 2016 12:08 am
by SteveD
We've ordered the newer teflon rms. Install dry or soaked?
http://www.ibmwr.org/r-tech/airheads/rearseal.shtml wrote:3. The seal must be installed dry, as it is a teflon impregnated paper sealing surface and has to be pre-formed-hence the special tool.
Retort: I don't know which seal you're talking about - BUT - the newest seal (one I got about 2 months ago) is BLACK, and must be installed WET. The instructions are VERY SPECIFIC about soaking it in engine oil for an extended period of time in order to soften it up before installing it. This was supposed to be the hottest "trick" seal from BMW. Mine was for an R65 - but I believe the exact same seal is used on all the later boxer's (/5 on).