Hi, i have an 84 k100 rs and it has the weep, actually its getting quite bad now so have purchased a seal set from motoworks, gave them the vin number as they asked, but found out recently that the pump underwent a change of design, what was this change and when was it implemented? I am assuming that I will get the correct type for my bike as its my only transport and i cant afford to hang around if the wrong parts are delivered!

As long as you also get the new stamped steel impeller along with the upgraded seal set you should be right. Have a good squiz through the various posts on the subject and you'll find what you need.

Ahh, I didnt order the impellor, best go back and have a look to see if they stock them!!

Motorworks dont stock the uprated impellers, though motobins do, however i dont have the correct debit card that they require, is there anyone else out there in the uk who stock them?

Jonno
I got the kit from motobins and it has all the bits you need if you have the
original cast impellor
I bought part numbers
Part No.41149K, seals etc £17.50
and
Part No.41177 steel impellor £7.35

i also had to buy another seal as I broke the first one cos i didnt RTFM
Part No.41150 £11.50

but its pretty straightforward really

I take it the mechanical seals are a bit brittle then,same as the cx 500,i managed to mangle a new one trying to fit it, the beemer looks easier tho'.

CX500 mech seals?
Done loads, my other bikes a CX........ .
Yep, its easier than dropping lumps a la CX
you just need to support the top of the mech seal when pulling the shaft through
I didnt, rushed things and broke it DOH!
I also found you need to pay attention on the face to face seal when refitting the pump to
the motor, or you may get oil weeping out.
It took me two goes to get that right.
As said, theres lots of info on the job here.

Edit:
its similar to a CX mech seal but the CX mech seal has two parts
the ceramic part sits in the impellor and butts up to the carbon face of the seal
the BMW is an all in one assembly which is why you need to take care.
Once you understand the caveats (and RTFM in my case) its quite easy

While I'm rantin on.......
When pulling the shaft through, STOP when the oil gear gets flush to the inner face
dont keep compressing the mech seal any more, it wont help
Also ensure the oil pump gears are fully home and flush with each face
before fitting the pump
A mate didnt get the smaller one fully seated and it sat proud of the face
so when he tightend up the pump bolts it cracked the casting. Ooh nasty !!
Tears before bedtime and all that and he had to buy a second hand pump.

Have taken all that on board, as you say at least you dont have to drop the lump out a la cx, it'll be nice to do it on a nice clean work bench!
By the way, when ordering the seal set,(i didnt know i needed the impeller) i had to quote the frame number,will i get the set for the older design allowing me to use the cast impeller?
sorry to cast confusion on this issue but it is a cause for concern and as i stated earlier it's my only form of transport at the moment and need it for work. anyway thanks for your help!!

Jonno
to quote the bins site
"K OIL/WATER PUMP KIT (CONSISTS OF 1x41150,41155, 41160, 41165 & 41175)
ALL K100 & K75 PRE 01/1994 REQUIRE 1 * 41177 IMPELLER"

I take that to mean you need to buy the new type impellor as well
Not sure if you can use those seals with the older cast type
and not sure if you can even get the old type seals anyway.
You may be safer just going the whole hog.

Once you get the outer cover off revealing the impellor
I expect you'll see loads of crap and stuff thrown up from the
front wheel in all the nooks and crannies.
before removing the pump assembly I suggest you take a bit of time to
clean it up as best you can to keep the nastys out of the oil/pump.
I used an old screwdriver, small paint brush and white spirit.

This wll also help you find all of the bolts, 7 in all I think
Its also a good idea to clean any crap out the heads before trying to remove the bolts
cos if one rounds off because the hex drive hasnt fully located, the job could turn into
a nightmare.
its good practise to work clean anyway.
I used a hex drive socket thingy rather than hex/allen keys
and glad I did, mine were pretty stiff and I was sweating when trying to remove then and muttering
"dont you round off on me you b*st*rds"
I copperslipped everything on reassembly so next time I dont have to struggle.
Stainless replacement bolts are also available.

i will get the new impeller and just take it easy till it turns up, the bike has only 9000 miles under its wheels and the coolant looks clean as does the oil, and the front of the engine has been cleaned up in readiness, luckily, working in an engineering environment, i can get my hands on almost any type of stainless fastener so that should help prevent any problems in the future!

Hi Jonno, I would suggest you also change the large gear in the oil pump for the later type if it has not already been done on your bike. The early type has the water pump impeller held on to the shaft by a nut, and the threaded portion of the shaft shears off very easily. It is easily checked by removing the water pump cover from the front of the pump. This is a known weak spot and later shafts have the impeller held on by a bolt which is threaded into the shaft. If you do like I did and chance it you will wreck the new water seal when you try to remove the shaft again. The gear/shaft is part No. 11535 on Motobins website, and the bolt is 11526. A complete oil/water pump is also available, which is what I fitted in the end. Take a look at the thread "Water pump seal special tool" on the forum.

Thanks, am now armed with the info I need, Its important I get this right, or i'll be forced to put the triumph back on the road,and its a horrible top heavy lump of a thing, to all you trumpet lovers, joking!

The early type has the water pump impeller held on to the shaft by a nut

Good point ! I never knew that
Its not in the Hyenas manual

I would take a guess that i will be needing a new style shaft ......will i?

works will flog you a later SH pump for £65
As they do a 14 day no quibble guarantee
its an option...............

sounds a bit more like it, think i may go down that road,i think it'll be less hassle,cheers chaps!!

jonno1962 wrote:I would take a guess that i will be needing a new style shaft ......will i?

No, you do not necessarily need a new shaft.
I did my double-pump a month ago, and re-used the old-style shaft, with the nut on the end.
I had no problems with that bit...

Good luck!

Rick

Well thank you, i have plenty of options to choose from, may go down the secondhand pump route seeing as i have a seal set anyway i can refurbish and fit, in a trice without any hassle,thank you all for your support, i look forward to bombarding you with more inane questions soon!!