Just stops running

[Jethroww]

Hi, Euro Motoelectrics is shipping everything except the vibration damper.  Would the pump filter screen
from Euro Motoelectrics  fit a pump damper from the beamerboneyard or the other places that sell
the vibration damper? Have put about 400 Kilometers so far on the bike without any problems.
Thanks for all the help.
Jethroww

[Laitch]

It's the pump diameter and the damper diameter that must be compatible. The cylindrical filter screens fit the 52mm pumps. The pump fits into the damper then the screen fits to the bottom of the pump. So when parts are ordered, it's important to know what you've got.

[Jethroww]

Hi Laitch,  I did measure and I have the 52 mm pump. The damper that's on now just feels
soft and it seems a bit swelled up. Had to force  the damper into the pump screen first .
Them the pump in. Seems to be working  ok.
Thanks  Jethroww

[Laitch]

You didn't remove the damper holder from the tank and do the assembly outside the tank?

[Jethroww]

Laitch  I did remove the damper and pump from the tank. Cleaned  and reassembled  it. New filter and reassembled
all back in the tank without any problems. Ran great today in this hot weather.
Jethroww

[know_fear]

Even a new damper is a tight fit.
Damper into the pump screen first, then slide the pump down into the damper.
WD-40 is your friend here.
Sounds like you've got it.

[Laitch]

I'll just join the TED talk going on here with these illustrations from the BMW K100/K75 Repair Manual downloadable from this site. :laughing4-giggles. Boringly, installation is the reverse of these steps.

[Jethroww]

Hi, I do have the Clymer manual.  It just seems the damper has swelled up a bit making it very hard to get the pump screen on . So that's why I put the pump screen on first. That's why I was thinking of getting a new damper.
Thanks  Jethroww

[Laitch]

Hi, I do have the Clymer manual.  It just seems the damper has swelled up a bit making it very hard to get the pump screen on . So that's why I put the pump screen on first. That's why I was thinking of getting a new damper.

Well, I guess aging is finally working its magic on my comprehension. First, the images aren't from Clymer; they're from BMW and have more detail. Secondly, the damper shouldn't make the pump screen "hard to get on" because you push the pump screen onto the pump after the pump has been installed into the damper.

But all this is fuel through the return line anyway, because you're back underway regardless of the convolutions in the route you took to get there. 

[Gabriel70]

Hi

I experienced a similar problem.
Intermittent shut down of the motorcycle.
Fortunately for me, I traced it back to the connector to the alternator.
It’s a spade connector and over time, became loose.
I tightened the connector and all is well.
Perhaps check all your electrical connections and ground points. Clean and retighten.
Throwing money and parts at your bike won’t always fix the problem.
Good luck!

[Jethroww]

Hi just an update,  been my daily driver since the repairs with no problems.
Laitch I was thinking of getting the - fit for E10 fits 52mm pump damper from
tills.de.  Would that be the better choice to prevent this  happening  again?
I will be buying 2. I am working/resurrecting a 1989 K100RS-SE
Thanks

[Laitch]

I was thinking of getting the - fit for E10 fits 52mm pump damper from
tills.de.  Would that be the better choice to prevent this  happening  again?

Jethroww, my dude, congratulations on your outcome, but botched assembly and neglect were likely the major factors in this incident and you can control them. In the tills list I'm reading, there is "no fit for E10" pump damper for a 52mm pump like the one you seem to have, only a "fit for E10" pump damper for a 43mm pump. All those dampers should be suitable for E10 if you ride your motorcycle plenty and not use it for a fuel storage dump.

By all appearances, your current pump is a 52mm therefore a 52mm damper is required, and probably a new pre-filter. Measure the K75 pump's diameter to verify and measure the K100's pump also because pumps get changed and swapped among some motos during their lifetimes and their measurements might not conform to the published specs for their model years. If a damper is firm and not "swollen" or gooey, it doesn't need to be replaced.

[Jethroww]

Hi Laitch,  I found the E10 when I clicked on the description. Here is the link.
https://www.tills.de/vibration-damper-fuel-pump-52mm-replacing-bmw-16121464628-and-bmw-16121450712-745-1077.html
Thanks Larry

[Laitch]

Clicking on the description—what a concept!    Get 'em if you need 'em. Mine has its original.

[Jethroww]

Hi, It's back. This morning going to work doing about  140 KMH. The bike just died again about 40 minutes into my commute.  Three lanes over to my right got on the shoulder and coasting.  Maybe about  15 seconds later still coasting the bike came back to life. Back up to 140 KMH and 20 minutes late made it to work without any problems. On the way home driving for about 1 hour. Hit a few red lights in town before the bike just died again. Tried starting it a few times and wouldn't start. Parked bike on shoulder of road and went to my appointment. Came back about an 1 hour  and 20 minutes  later.  The bike just started right up. It did cut out about 2 minutes late but instantly  came back to running  with no problems.  Made it home in about 20 minutes with no other problems.  I thought I had found the problem as a bad/corroded fuel pump conection under the seat last time. I cleaned it a few times with Deoxit and put a small amount of dielectric grease on the connection. I now have 138,584 kilometer on the bike. Will give another good cleaning to the connector and hope that fixes it. Any other ideas to solve this problem would be appreciated.

[frankenduck]

It's usually either a flaky ignition switch or power to the fuel pump. And even though you cleaned the ignition switch it still might be flaky

Here's what I'd do to diagnose:

Get a couple of 12V LEDs.  Wire one between ground and the green wire from the ignition switch. Wire the other to ground and the green/white wire on the tank side of the connector.

Tape the LEDs to the front of the dash pad so that you can see them while riding.

If the ignition switch LED goes out when the bikes dies then you probably need a replacement ignition switch.

If the ignition switch LED stays on but the fuel pump one goes out then it's probably the fuel level sender connector.

If both stay on when the bike dies then it could be a flaky connection where the fuel pump power passes thru the fuel level sender.

(PosiTaps are useful for tapping into wires.)

[Laitch]

Hit a few red lights in town before the bike just died again. Tried starting it a few times and wouldn't start

Does that mean it would crank but wouldn't start, or wouldn't even crank?

[Jethroww]

Hi, will try and get some 12volt led lights and see if that works.
The bike cranks over just won't fire/start. The lights on the dash
 still work and it seems everything else is working.  Just seems
like a kill switch was pushed. It doesn't miss or sputter/lug etc.
Just stops running/firing with everything else working.

[The Mighty Gryphon]

The ignition switch on my K75RT does the same thing every 4-5 years.  A good cleaning as and careful reassembly fixes it.  That switch is a piece of poorly designed crap.  There is almost no pressure pushing the contacts together.  The smallest spec of crap will break the connection.

[Jethroww]

Hi, will clean the ignition  switch again. Might try and find a stronger spring for the switch.
Thanks

[frankenduck]

Another thing that might be worth checking/cleaning is the kill switch:

http://www.kbikeparts.com/classickbikes.com/ckb.tech/0.ckb.tech.files/startkillrehab/startkillrehab.htm

[Jethroww]

Hi, cleaned start/kill switch. The picture on the white paper is before I cleaned it.

20220820_193057.jpg (30.59 kB . 576x576 - viewed 305 times)
20220820_193135.jpg (29.62 kB . 576x576 - viewed 359 times)
20220821_185159.jpg (34.65 kB . 576x576 - viewed 370 times)[attachment id=4

Have bought 2 12 volt led bulbs to attach as frankenduck suggested to see which one goes out when bike stalls.
Only problem is I can't find the  PosiTaps here in Cambridge Ontario Canada.  Any suggestions on were I could get
some would be appreciated.
Thanks
][/attachment]

[Laitch]

Here's what happened when I put the words positap canada in Google's search window and click to search.
https://motorcycleinnovations.ca/products/posi-tap-connectors-16-18-ga You could also order through Amazon. I haven't found them locally in Vermont so have always bought them online.

[The Mighty Gryphon]

If you can't find the Positaps locally, you can accomplish the same thing with a couple straight pins and some alligator clip test leads. 

Carefully push the pin into the wire you want to test, no need to go all the way through, just far enough to reach the conductor inside.  Clamp the alligator clip test lead to it and connect to your test equipment. 

When you are done pull out the pin.  The hole is very small, but if you are concerned about water getting in, you can seal it with a drop of nail polish or paint.

[Jethroww]

Hi, just thought I would mention that about 4 weeks ago my fan stopped working . Ordered a Spal and installed it. The old one was completely melted together.  I do have the switch installed to turn it on. Could this heat from melting the fan contribute to this engine just stopping? Should I take the tank off and clean the 2 big switch wires? Waiting for the Posi Taps to try and see if that could be the problem.    Thanks