Water pump seals

Rockman · 1 Water pump seals Sun Feb 02, 2014 6:26 pm

Rockman

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Number of posts : 517

My K100 has had a small oil leak from the seal behind the water pump for as long as I have had it (about 20000ks) but lately it has been getting worse. So I decided to change the seals. Ordered a kit from Motobins. Took it all apart no worries. Followed the instructions that came with the seal set when refitting. No oil leak now, but it pisses coolant out at an alarming rate. Obviously I've damaged the water seal Sad

, so I'll have to start again. No oil leak though Very Happy

I have 2 questions,

firstly, what is the best way to get the old seal out. I resorted to butchery with a screwdriver and a hammer first time, but maybe there is a better way??

and more importantly, what is the best way to put the new water seal in. I tried the "draw it in with the bolt" method recommended by motobins. This didn't work. My manual recommends using a large socket and carefully tapping it in. My thoughts are that the socket method is better because it doesn't put pressure on the centre part of the seal but I'm open to suggestions.

Rick G · 2 Re: Water pump seals Sun Feb 02, 2014 7:47 pm

Rick G

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I use a socket and a small press (a 6" vice will do the job) as for tapping it in well they are a ceramic seal and you could gently tap auntie flo's delf china but London to a brick it will break
As for getting them out brutality wins every time.
Have you used the pressed steel impeller because if you use the cast impeller the seal will shatter first time you run the engine. If you take 3mm off the boss of the cast impeller it will be OK.

Rockman · 3 Re: Water pump seals Sun Feb 02, 2014 8:03 pm

Rockman

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RicK G wrote:I use a socket and a small press (a 6" vice will do the job) as for tapping it in well they are a ceramic seal and you could gently tap auntie flo's delf china but London to a brick it will break
As for getting them out brutality wins every time.
Have you used the pressed steel impeller because if you use the cast impeller the seal will shatter first time you run the engine. If you take 3mm off the boss of the cast impeller it will be OK.

Thanks Rick, the vice idea seems a good one, so I'll try that. I also thought of using a socket to put the load on the outside flange of the seal and drawing it in with the shaft and bolt. Similar principle I suppose. I have the pressed steel impeller. On a side note, I have a second rubberised washer thing which was fitted between the seal and the spacer. I just reused this as there wasn't a new one with the kit. I assume it just seals the shaft from coolant leaking back along it. Is it ok to reuse?

Rick G · 4 Re: Water pump seals Sun Feb 02, 2014 8:07 pm

Rick G

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You do have to use the outside flange or it will more than likely break the seal. Draw the shaft through with a bolt and large washer on the top section not the flange.

Inge K. · 5 Re: Water pump seals Sun Feb 02, 2014 11:16 pm

Inge K.

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Rockman wrote:
On a side note, I have a second rubberised washer thing which was fitted between the seal and the spacer. I just reused this as there wasn't a new one with the kit.

??? Haven't seen that in any parts diagram, do you got a picture?

Could it be remains of the old seal? it have been a lot of different ones along the years.

It could be that this have added pressure to the ceramic seal and destroyed it,
depends on how thick and hard this extra part is.

Rockman · 6 Re: Water pump seals Sun Feb 02, 2014 11:32 pm

Rockman

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Number of posts : 517

Inge K. wrote:

Rockman wrote:
On a side note, I have a second rubberised washer thing which was fitted between the seal and the spacer. I just reused this as there wasn't a new one with the kit.

??? Haven't seen that in any parts diagram, do you got a picture?

Could it be remains of the old seal? it have been a lot of different ones along the years.

It could be that this have added pressure to the ceramic seal and destroyed it,
depends on how thick and hard this extra part is.

No pic - its still in the bike. About 2mm thick, same dia as the spacer. rubber in the centre and steel outer. Like a washer. I assembled it without it first time and it leaked, I then put it in place where it came from between the spacer and the seal and it still leaked. When I pull it apart again I'll post a pic.

New seals ordered from motobins. Took a week or so last time.

Inge K. · 7 Re: Water pump seals Sun Feb 02, 2014 11:40 pm

Inge K.

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A unknown part to me.....don't know if others in here.......Rick, Duck?

Rick G · 8 Re: Water pump seals Sun Feb 02, 2014 11:46 pm

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It is a part of the old seal, they have a tendency to fall out in bits but strangely enough still seem to work fairly well while you leave them alone.

Rockman · 9 Re: Water pump seals Mon Feb 03, 2014 5:57 pm

Rockman

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RicK G wrote:It is a part of the old seal, they have a tendency to fall out in bits but strangely enough still seem to work fairly well while you leave them alone.

Ah!

brickrider · 10 Re: Water pump seals Fri Feb 07, 2014 11:30 pm

brickrider

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I changed the oil in my '85 K100RS in the course of putting her to bed for the cold months. I found a wee bit of coolant in the belly pan at that time, so I took a keen interest in this thread. I also viewed a (fairly bad) video on YouTube on replacing the oil/coolant pump seals. Today I was at the local dealer for a another part and I asked if a kit was available or if a number of parts must be purchased separately. As it happened the mechanic was at the parts desk and he advised I remove the pump and bring it in for repair, as some special tools are required to do the job properly. The parts man observed that customers who do it themselves often return for a second seal. I'm inclined to follow that advice this Spring when I bring her out of winter's sleep.
I was also advised to use BMW coolant, as "Prestone ruins the seals."
What sort of credence should I give this? Is it true the brand of coolant makes a difference? Is this merely an attempt to sell expensive, branded consumables?

Rockman · 11 Re: Water pump seals Sun Feb 09, 2014 5:42 pm

Rockman

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Number of posts : 517

brickrider wrote:I changed the oil in my '85 K100RS in the course of putting her to bed for the cold months. I found a wee bit of coolant in the belly pan at that time, so I took a keen interest in this thread. I also viewed a (fairly bad) video on YouTube on replacing the oil/coolant pump seals. Today I was at the local dealer for a another part and I asked if a kit was available or if a number of parts must be purchased separately. As it happened the mechanic was at the parts desk and he advised I remove the pump and bring it in for repair, as some special tools are required to do the job properly. The parts man observed that customers who do it themselves often return for a second seal. I'm inclined to follow that advice this Spring when I bring her out of winter's sleep.
I was also advised to use BMW coolant, as "Prestone ruins the seals."
What sort of credence should I give this? Is it true the brand of coolant makes a difference? Is this merely an attempt to sell expensive, branded consumables?

If you have a dealer local to you, taking it in is probably the way to go. Doesn't take long to fit the seals. The nearest one to me is about 4 hours away and I wouldn't deal with them in any case (another story), so I'm stuck with doing it myself.

As for the coolant, sounds to me like "an attempt to sell expensive, branded consumables".

Rick G · 12 Re: Water pump seals Sun Feb 09, 2014 7:02 pm

Rick G

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I changed the oil in my '85 K100RS in the course of putting her to bed for the cold months. I found a wee bit of coolant in the belly pan at that time, so I took a keen interest in this thread. I also viewed a (fairly bad) video on YouTube on replacing the oil/coolant pump seals. Today I was at the local dealer for a another part and I asked if a kit was available or if a number of parts must be purchased separately. As it happened the mechanic was at the parts desk and he advised I remove the pump and bring it in for repair, as some special tools are required to do the job properly. The parts man observed that customers who do it themselves often return for a second seal. I'm inclined to follow that advice this Spring when I bring her out of winter's sleep.
I was also advised to use BMW coolant, as "Prestone ruins the seals."
What sort of credence should I give this? Is it true the brand of coolant makes a difference? Is this merely an attempt to sell expensive, branded consumables?

This man speak with forked tongue. No "special" tools are needed and no "special" coolant is needed but a some knowledge of seals and water pumps is needed.
Any mechanic who thinks a "special" tool is needed to do that job is a Tool

brickrider · 13 Re: Water pump seals Sat Feb 15, 2014 11:34 pm

brickrider

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Number of posts : 559

I was also told by the dealer's mechanic that BMW had modified the design of the pump impeller. If I remember correctly my 1985 K100RS should have a cast one as it came from the factory; the part was subsequently changed to a pressed steel item. I was advised I must buy the new one, as the seal for the old one is no longer available. I consulted a parts fiche and couldn't locate any impeller at all, cast or pressed steel.
What's a shade tree mechanic to make of this? Rolling Eyes

Rick G · 14 Re: Water pump seals Sat Feb 15, 2014 11:42 pm

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machine 3mm from the boss of the impeller

MikeP · 15 Re: Water pump seals Sun Feb 16, 2014 12:58 am

MikeP

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brickrider wrote: I consulted a parts fiche and couldn't locate any impeller at all, cast or pressed steel.

BMW call it a "rotor".

Part #11 41 1 461 173

Item #14 here (ignore the look of the thing in the image though)

Water pump seals B0003650

charlie99 · 16 Re: Water pump seals Sun Feb 16, 2014 4:22 am

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heres a pic of the updated parts from motobins ...but i'm sure available everywhere
just for clarity

you will notice that there is a spacer to make up the difference between the cast impeller removal and the newer pressed impeller type
https://i.servimg.com/u/f57/16/13/61/46/41149k11.jpg
Water pump seals 41149k11

the newer impeller
https://i.servimg.com/u/f57/16/13/61/46/4117710.jpg
Water pump seals 4117710

85 had the nut on the thread ...rather than the bolt into the shaft to hold the impeller
just hope that the thread doesn't break off the shaft ...go carefully
here is the newer designed shaft
https://i.servimg.com/u/f57/16/13/61/46/1153510.jpg
Water pump seals 1153510

hope it helps

good luck !

brickrider · 17 Re: Water pump seals Sun Feb 16, 2014 5:07 pm

brickrider

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Thanks for the clarification. Very Happy

gabriel · 18 Re: Water pump seals Mon Feb 17, 2014 3:39 am

gabriel

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Hi
Inge and rick are correct. The metal spacer you described is part of the old seal.
It forms the top part of the old seal and sits flush against the bottom half of the seal to create a watertight seal.
Ibmwr? Includes a photo of the water seal and the spacer you described is visible underneath the plastic cap with the tabs which break off when the seal is installed.
You should consider removing the spacer from your bike. The newer version of this seal does not have this spacer/washer.
Hope this helps.
Cheers

Inge K. · 19 Re: Water pump seals Mon Feb 17, 2014 9:05 am

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gabriel wrote:the spacer you described is visible underneath the plastic cap with the tabs which break off when the seal is installed.

gabriel · 20 Re: Water pump seals Mon Feb 17, 2014 10:01 am

gabriel

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Hi Inge

I have a leaking wAter pump and I have purchased the older version of the water seal which is displayed in the photo you recently posted.
My question is how much of the plastic cap is retained when the seal is installed?
I know the eight tabs break off, but what about the main body of the plastic cover.
I have the cast impeller but I want to try and replace the seals using the existing impeller.
Cheers

Inge K. · 21 Re: Water pump seals Mon Feb 17, 2014 10:10 am

Inge K.

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When the tabs have breaked, rest of the plastic cap should be removed.

brickrider · 22 Re: Water pump seals Tue Mar 25, 2014 12:00 pm

brickrider

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My K100RS has a slight drip of coolant when it's parked in the garage. I'm not in a position to repair it just now. My question: is the seal likely to fail catastrophically in the near future, or will the leak gradually increase? I'd like to continue riding it for a bit longer, but don't fancy being stranded on the side of the highway.

charlie99 · 23 Re: Water pump seals Tue Mar 25, 2014 2:09 pm

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just keep an eye on the reservoir ,,,and when the bike is actually running , given enough fluid level
you should be able to squeeze the lower radiator hose as it goes into the pump (the one that goes through the crankcase )
you should be able to see the reservoir level rise and fall with the thumb - forefinger press on that hose

don't think we have seen a major failure ...except for during fan failure in stopped highway traffic

the real issue is when the high pressure oil pump seal is also gone and floods the water system with oil as well (if the breather vent has become clogged )

brickrider · 24 Re: Water pump seals Sun Mar 30, 2014 1:31 pm

brickrider

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"the real issue is when the high pressure oil pump seal is also gone and floods the water system with oil as well (if the breather vent has become clogged )"
Hummm. That is a scary scenario! Is that seal likely to fail about the same time as the coolant seal?
I've really got to attend to this before the riding season here begins in earnest.
Let me pose another question that may sound stupid.... when I pull the pump, I understand the coolant must be drained. But, must the oil be drained as well?
Thanks in advance for keeping me out of trouble. It isn't always easy being a bush mechanic.... Laughing

kartooo · 25 Re: Water pump seals Sun Mar 30, 2014 3:29 pm

kartooo

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Number of posts : 80

brickrider wrote:"the real issue is when the high pressure oil pump seal is also gone and floods the water system with oil as well (if the breather vent has become clogged )"
Hummm. That is a scary scenario! Is that seal likely to fail about the same time as the coolant seal?
I've really got to attend to this before the riding season here begins in earnest.
Let me pose another question that may sound stupid.... when I pull the pump, I understand the coolant must be drained. But, must the oil be drained as well?
Thanks in advance for keeping me out of trouble. It isn't always easy being a bush mechanic....

just did mine a 1985rt and i have done a few others in the past.
yes, drain the engine oil, just save it and re-use if it's too early for a change.
i had the early "nut" version shaft. it was badly pitted and i sprung for the big $$ new shaft.
your anxiety will pass when you get into it. knowing you have all nice new parts in there will make you regain confidence in the bike again.
mine had a small engine oil weep outta the drain hole. i was just going to put it off until the fall.
crappy weather still here so i dug into and got it over with. after you have done a few i'd say about an hrs time.

Larry

charlie99 · 26 Re: Water pump seals Sun Mar 30, 2014 3:42 pm

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I don't think that the water seal letting oil in is an issue in itself ,as its more or less a pressure seal in one direction ....the real issue is letting the oil in to spoil the water system ...

if you are seeing drops of water under the sump hopefully the breather is still open... well sounds like it this wont happen .

I think the blockage happens when the oil seal weeps and it goes on for a long while, attracting debris to accumulate and then partial blockage just below the air gap between both the seals along the impeller shaft at the top of the breather port .

the oil pump doesn't hold that much oil ...but still enough to put a big stain on concrete .
because the oil picks up from a tube that extends to the bottom of the sump the oil level is below the pickup tube feed into the pump , I haven noticed it drained the oil pan when done

...just make sure that after the process is done and you have confirmed that all is well ,,,(test ride etc )

there will likely be dags of sealant in both the oil and water paths so go carefully with the quantity of sealant used

you will find the sealant collects in the radiator input side and hopefully not much in the oil ,,,which then feeds straight to the filter before to the rest of the bike engine .

change the oil and filter , then drain the water and clean out the radiator (maybe some suction device would be good for this as the left hand tank-feed is deeper than your fingers )

Inge K. · 27 Re: Water pump seals Sun Mar 30, 2014 7:03 pm

Inge K.

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Be aware so you don't fill the oil return passage with sealant, or you would get a leak from a different place than earlier.

Water pump seals Retur_10

Gergely · 28 spare parts, water/oil seals Mon Mar 01, 2021 2:13 pm

Gergely

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Number of posts : 48

Hi! I ride a K75 from 1991 for 12 years as 3rd owner, made 40k kms approx in this period. Now 56k ...but counter has stopped 2 yrs ago. Only minor services till now (tyres, oils, filters, spark, fuel pump). Now I have mayor issues with ignition...probably clutch free wheel and water/oil pump rebuild (with bad results by now). I read a lot your stories but I need to ask also.... thanks for the possibility to do so! Greg

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1 Water pump seals Sun Feb 02, 2014 6:26 pm

Rockman

2 Re: Water pump seals Sun Feb 02, 2014 7:47 pm

Rick G

3 Re: Water pump seals Sun Feb 02, 2014 8:03 pm

Rockman

4 Re: Water pump seals Sun Feb 02, 2014 8:07 pm

Rick G

5 Re: Water pump seals Sun Feb 02, 2014 11:16 pm

Inge K.

6 Re: Water pump seals Sun Feb 02, 2014 11:32 pm

Rockman

7 Re: Water pump seals Sun Feb 02, 2014 11:40 pm

Inge K.

8 Re: Water pump seals Sun Feb 02, 2014 11:46 pm

Rick G

9 Re: Water pump seals Mon Feb 03, 2014 5:57 pm

Rockman

10 Re: Water pump seals Fri Feb 07, 2014 11:30 pm

brickrider

11 Re: Water pump seals Sun Feb 09, 2014 5:42 pm

Rockman

12 Re: Water pump seals Sun Feb 09, 2014 7:02 pm

Rick G

13 Re: Water pump seals Sat Feb 15, 2014 11:34 pm

brickrider

14 Re: Water pump seals Sat Feb 15, 2014 11:42 pm

Rick G

15 Re: Water pump seals Sun Feb 16, 2014 12:58 am

MikeP

16 Re: Water pump seals Sun Feb 16, 2014 4:22 am

charlie99

17 Re: Water pump seals Sun Feb 16, 2014 5:07 pm

brickrider

18 Re: Water pump seals Mon Feb 17, 2014 3:39 am

gabriel

19 Re: Water pump seals Mon Feb 17, 2014 9:05 am

Inge K.

20 Re: Water pump seals Mon Feb 17, 2014 10:01 am

gabriel

21 Re: Water pump seals Mon Feb 17, 2014 10:10 am

Inge K.

22 Re: Water pump seals Tue Mar 25, 2014 12:00 pm

brickrider

23 Re: Water pump seals Tue Mar 25, 2014 2:09 pm

charlie99

24 Re: Water pump seals Sun Mar 30, 2014 1:31 pm

brickrider

25 Re: Water pump seals Sun Mar 30, 2014 3:29 pm

kartooo

26 Re: Water pump seals Sun Mar 30, 2014 3:42 pm

charlie99

27 Re: Water pump seals Sun Mar 30, 2014 7:03 pm

Inge K.

28 spare parts, water/oil seals Mon Mar 01, 2021 2:13 pm

Gergely

29 Re: Water pump seals

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