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16Back to top Go down   oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 Empty RE: Oil Leak from oil pump hole Tue Jul 13, 2010 8:36 am

Dennis


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The reason for the metal to metal joint and not a gasket is because the oil pump is a gear pump, which relies on minimal end clearances for efficiency. So use of a gasket would cause that efficiency to be compromised, and in a worst case scenario, if some one was to make a gasket which was too thick the the result would be very low oil pressure and reduced flow.
Also, the metal joint assures perfect alignment with the drive, which in this case is from the end of the output shaft.
The reason for leaks when using silicone (sometimes) is because the oil pump internal pressure could be as much as 70 PSI (4.8 Bar) when the engine is cold, so there is some serious pressure acting on the case to pump joint.
Hope this helps to understand the reason for attention to detail when assembling the pump back onto the engine block.
Spend time getting everything clean, do not touch the joint faces with a file as any damage will cause a leak.

    

Crazy Frog

Crazy Frog
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If the cover is leaking due to small scratches, you could take your pump to a good hydraulic shop to have the pump and cover corrected on a lapping machine. A lapping machine is like a turn table with an extremely flat surface and using a very fine grinding compound (800 to 1200 grits).
After an hour on the lapping machine, the pump body and cover surfaces will have a mirror finish.
In order to lap the pump, everything has to be removed from the body (oil and water seal too affraid).

Here is what a lapping machine looks like:
oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 Lapping%20Machine


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oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 Frog15oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 Logo2101986 k75, 1985 K100rt, 1985 K100rt/EML GT2 sidecar, 1999 K1200lt/Hannigan Astro Sport sidecar.
    

Kerswellcrank

Kerswellcrank
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Scottie, sorry to have sent your thread off on a tangent, but the oil pump is one of those topics that seems to have have affected a lot of us.

Once again, I'm amazed and grateful for the wealth of knowedge and experience from the folks on this forum

Cheers,
Steve.

    

Avenger GT

Avenger GT
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When I fitted the new pump I used Loctite 5920 Premium Copper Silicone. I also used it on the timing chain cover. So far so good 600 miles later. I always use the least amount of silicone or any other gasket maker I can on any mating surface and after 40 odd years building and repairing engines I dont think I have ever had to re-make a joint for a leak. There is nothing worse than a pile of silicone sticking out of a joint, because you can be sure that there is just as much sticking into the engine, breaking off and going where it's not wanted! oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 Icon_cool

    

blaKey

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I like the lapping machine, but in the past I have used a sheet of glass and a sheet of wet-and-dry paper clamped to it.
Keep the paper wet and move the piece in a figure 8 fashion until the mating surface is nice and shiny.

Of course you may not be able to do this on every part that requires a clean mating surface, but it works a treat on those bits you can.


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Neil
K100RS 1986 RED!

Dress for the ride and the potential slide.
    

k75c-nz

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Hi Steve, if you are in doubt then yes, you should check it.
Its not too much bother and will give peace of mind if nothing else.

I have been trying to find the web page that guided me though this, but it had a page from the Klymer manual outlining the refitting of the pump and this return channel, so perhaps you can track that down?

This is an odd thing as the pump on my K75 did not have a matching hole, was blank, but the hole is in the block and it was full of silicon, a real neat plug of it attached to the pump!

Just the slightest smear in the pump is all it requires as alluded to by AvengerGT above!
When I had the flywheel off to replace the rear main seal, I spent quite some time removing little silicon threads that had become lodged in the splines in this area, obviously propagated from other locations via oil delivery(no thanks to heavy handed application)!

I am not sure of the risk of damage, but is the cause of oil leaks around the pump as the high pressure return to the sump has no path and forces its way out wherever it can once that channel is blocked.

Its so small that you would not think it relevant but as soon as I had the pump off, it made sense as that was the area that the pump was leaking from.

Was really odd for me as the front main seal was also leaking, previous owner or dealer had replaced this, but in the assembly process had managed to get the seal to invert and crankcase pressure would force oil out the front of the engine and out this hole also.
I fixed that and then found the leak around the pump some time later when I noticed that it was still making the oil pressure sensor wet with oil!!

Good luck!

    

Kerswellcrank

Kerswellcrank
active member
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Right then, I've taken my pump back off to check that the groove isn't blocked (it isn't), but I don't understant what the groove is for.

One end meets up with a small hole in the crankcase face (circled red in the photo's). But the other end goes nowhere. I've scraped the groove looking for a blocked hole in the oil pump itself but there is no hole. neither is there a hole in the crankcase. As far as I can see it's a dead end.

There is a small square hole in the pump too (circled blue), This seems to be blank as well, and doesn't join to the groove.

Can anyone shed any more light on what the groove is for, as I just can't figure it out, and I'm reluctant to just put the pump back on in case there is something wrong that I am missing.

Many thanks,
Steve.
oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 OilPump1a oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 OilPump2a

    

Crazy Frog

Crazy Frog
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You really like to quiz us..
I don't have any definitive answer, but here is what I think. This small hole (circled in red) is on the pressure side of the pump. It may be there to catch any leak on the mating surfaces of the pump/engine assembly. It seems to be a simple return to the crankcase.
The curved groove also reduces the area of the mating surfaces. Without any seal, a larger surface would be more difficult to perfectly mate.

Could you take a small wire and poke the hole to see if its open to the inside of the crank case? This would reinforce my theory.

Just for everybody information, because the pump being mounted at the end of the output shaft, when running the engine at full rpm,the oil debit riches 3,500 liters/hour or almost 1 liter/second. In comparison, the same type of gear pump mounted on a /5 flat twin gives only 1,4 liters/hour.

Here is a schematic of the oil circuit. You will notice that this oil passage is not represented on it.

oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 Oil-pa10


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oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 Frog15oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 Logo2101986 k75, 1985 K100rt, 1985 K100rt/EML GT2 sidecar, 1999 K1200lt/Hannigan Astro Sport sidecar.
    

Avenger GT

Avenger GT
Life time member
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You have the later type pump. The early type does not have that groove. The small gear is larger on the old pump and the mating surface ofthe pump is narrower at this point. There are two square holes which go nowhere. I took comparison pictures when I was fitting the new pump, but I can't get them onto the site for whatever reason. Must be doing something wrong. oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 Icon_scratch

    

ReneZ

ReneZ
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I think Bert is right here. The groove was made to ensure the mating surface is more or less equal between the bolts. This is very important as it is a steel on steel connection with just a tiny bit of sealant in between. It is really important that the pressure on all the area where the pump meets the block is the same.
It would be interesting to know if BMW applied the sealant to the inner surface in way of the groove or left it out, creating a preferred 'bleed' opportunity. If the pump is not bolted right (with the right sealant) to the engine they will sweat at the seams.


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Greetings from Florida Australia! Having a 'new' K     Surprised-o: 

Rene


BMW K100 - 1985 (0030029) Scotland oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 Rain
BMW K1200GT - 2003 (ZK01223) Florida
BMW K1200GT - 2004 (ZK27240) Australia
    

ReneZ

ReneZ
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Life time member
I wonder about AGT's comments above; as far as I know the pumps are exactly the same, but the newer ones had finer teeth (more teeth per circumference).lOve to see those photos!


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Greetings from Florida Australia! Having a 'new' K     Surprised-o: 

Rene


BMW K100 - 1985 (0030029) Scotland oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 Rain
BMW K1200GT - 2003 (ZK01223) Florida
BMW K1200GT - 2004 (ZK27240) Australia
    

Avenger GT

Avenger GT
Life time member
Life time member
oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 Bmw_pu17



Pic of pumps; old type on left, new type on right.

    

ReneZ

ReneZ
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I stand corrected, you were right! oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 Icon_biggrin I can see why you wanted to replace the old one!


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Greetings from Florida Australia! Having a 'new' K     Surprised-o: 

Rene


BMW K100 - 1985 (0030029) Scotland oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 Rain
BMW K1200GT - 2003 (ZK01223) Florida
BMW K1200GT - 2004 (ZK27240) Australia
    

Kerswellcrank

Kerswellcrank
active member
active member
Ah, so there are two types of pump! It looks like on the earlier pump the small oilway in the crankcase might have been lined up with the main oil cavity of the pump, and maybe on the later pump the small oilway is redundant.

I poked a piece of stiff wire about 150mm long into the oilway and it felt partially blocked, but after pushing it in an out it a few times it now feels clear, and the wire pushes in all the way , so I assume the oilway is just open to the sump.

It's all back together again now, and seems leak free. I ended up using high temperature silicone again (but a smaller amount) as I couldn't source anything else locally and needed to get the bike useable again quickly. So fingers crossed that it lasts ok.

Cheers for the interesting and educational info.
(I love this forum) oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 Icon_cheers

Steve

    

Crazy Frog

Crazy Frog
admin
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Kerswellcrank wrote: I poked a piece of stiff wire about 150mm long into the oilway and it felt partially blocked, but after pushing it in an out it a few times it now feels clear, and the wire pushes in all the way , so I assume the oilway is just open to the sump.
Steve
Thanks for testing that. it reinforce my theory.

Kerswellcrank wrote:
Cheers for the interesting and educational info.
(I love this forum) oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 Icon_cheers

Again we all learned from this post. Thanks to Avenger GT to share the pictures of the 2 pumps.
This forum is like riding a bike. If one find a biker stranded on the road, I believe that we (all of us) would stop to offer assistance.


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oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 Frog15oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 Logo2101986 k75, 1985 K100rt, 1985 K100rt/EML GT2 sidecar, 1999 K1200lt/Hannigan Astro Sport sidecar.
    

k75c-nz

avatar
active member
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That is really good to see the difference between the pumps.
Bugger, I have an old style on my K75 and yet I thought they had the newer ones.
It is dated 85 so must be right on the cusp of changes.
As long as both the galleys are clear it is all well.
Really dumb though that the return channel is so small, but I read that it is only used when the oil is not able to get fully circulated, ie a high pressure relieve path of some sort.

All is good in the wonderful world of Bayerische Motoren Werke AG !

    

Finally_A_K

Finally_A_K
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Silver member
Like a Band of Brothers Bert.....

Rick

    

33Back to top Go down   oil water pump - Oil leak from oil pressure sensor wire hole - Page 1 Empty Question Sat Apr 21, 2018 4:12 pm

Postman

Postman
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ReneZ wrote:I think Bert is right here. The groove was made to ensure the mating surface is more or less equal between the bolts. This is very important as it is a steel on steel connection with just a tiny bit of sealant in between. It is really important that the pressure on all the area where the pump meets the block is the same.
It would be interesting to know if BMW applied the sealant to the inner surface in way of the groove or left it out, creating a preferred 'bleed' opportunity. If the pump is not bolted right (with the right sealant) to the engine they will sweat at the seams.

An old topic but interesting. I had to remove my repaired water pump because I put too much sealant (Permatex Right stuff) and oil pressure light didn't come off at all. When I opened the pump I realizer that "groove was full on sealant and a tiny hole was partly closed also. So I really f****d up my pump installation [smiley]https://2img.net/i/fa/i/smiles/icon_sad.gif[/smiley] 

Permatex tube head is not good to make thin line of sealant. Next time I don't use this original head and I'll use hypodermic syringe that I can control the pressure.

All I want to know is do I have to seal around this groove or can I use sealant only outside of the groove?

    

Rick G

Rick G
admin
admin
Just around the outside would be fine.


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"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1999 K1100 LT with a Big Block 1200
    

Postman

Postman
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How about O-ring part? Also sealant outside O-ring?

Sent from Topic'it App

    

Dai

Dai
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Life time member
Not needed.


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1983 K100 naked upgraded to K100LT spec after spending time as an RS and an RT
1987 K100RT
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