Author Topic: 4yr stored k75--prob?  (Read 1193 times)

Offline BZABILL1

  • Curious
  • Posts: 2
4yr stored k75--prob?
« on: November 04, 2019, 11:05:43 PM »
Mate has aquirred k75 stored with fuel for abt 4 yrs in temparate to hot dry area.    apart from battery, what should we look closely at to make run/ridable?   I used to have an r60/2, but this is his first bmw.  We re diy'ers from way back, but know our limits.    A competent inspection is prob a good investment.
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Offline Stumpy

  • Motobrick Curious
  • Posts: 10
Re: 4yr stored k75--prob?
« Reply #1 on: November 05, 2019, 12:20:31 AM »
Drain the tank and check for corrosion. Look at the fuel pump and it’s mountings, they tend to rot, I would replace them.
Clean out the fuel rail.

Check the condition of the wiring, plugs and the regulator / rectifier.
Most problems with the K’s is the electrics, the wiring is getting old and brittle.
  • Croydon
  • K100RT

Offline Laitch

  • Redline 7000
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Re: 4yr stored k75--prob?
« Reply #2 on: November 05, 2019, 12:49:06 AM »
. . . apart from battery, what should we look closely at to make run/ridable?   
As an addendum to Stumpy's astute list:
  • the fuel hoses within the tank should be replaced
  • the fuel filter should be replaced
  • the breather hose from the crankcase to the air box should be inspected for cracks or replaced outright
  • the spark plugs should be replaced with ones that have had the gaps checked
  • the vacuum caps on the throttle bodies should be inspected and replaced if necessary
  • the air filter should be removed, tamped on the floor to remove dirt then reinstalled
  • the muffler should be checked for obstruction by rodents, wasps or stashed contraband.
Before trying to start it, the spark plug of each cylinder should be removed and the cylinder sprayed with fogging oil to help seal the rings in a bid to increase compression and aid starting. Maybe you won't need to clean all the the electrical connectors—including the four-pin fuel pump connector, the electronic ignition control unit connector, and the fuel injection control unit connector—but you should. :-) After that, it's good to go, maybe. Before you roll off on the vision quest, check the valve clearances, balance the throttle bodies and replace the tires.

ˇHasta la vista!
  • Along the Ridley in Vermont.
  • 1995 K75 72,000 miles
I wept because I had no radials until I met a man who had no splines.
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Offline BZABILL1

  • Curious
  • Posts: 2
Re: 4yr stored k75--prob?
« Reply #3 on: November 05, 2019, 03:11:24 AM »
tks.  that starts us off.  btw, fuel pump-repair/flushable if fuel gone jelly?
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Offline Laitch

  • Redline 7000
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  • Posts: 7755
Re: 4yr stored k75--prob?
« Reply #4 on: November 05, 2019, 07:57:11 AM »
  • Along the Ridley in Vermont.
  • 1995 K75 72,000 miles
I wept because I had no radials until I met a man who had no splines.
https://tinyurl.com/RillRider

Offline volador

  • ^ SuperNatural Motobricker
  • Posts: 892
  • NEEDS MORE CHROME
Re: 4yr stored k75--prob?
« Reply #5 on: November 05, 2019, 09:09:32 AM »
tks.  that starts us off.  btw, fuel pump-repair/flushable if fuel gone jelly?

Soak fuel pump in kerosene, mineral spirits or comparable
With some test leads reverse polarity to the pump will expel any crud
  • NYC NY
  • 1991 K100RS 1993 K75S ABS
5 BOROUGHS SISYPHEAN SOCIETY  MAINTAINING THE OBSESSION

Online Martin

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  • Posts: 4162
Re: 4yr stored k75--prob?
« Reply #6 on: November 05, 2019, 02:03:17 PM »
If left for too long pumps can suffer from corrosion internally. And it  has been reported that the seals can dry out, and while the pump may run the pressure will be too low.
Regards Martin.
  • North Lakes Queensland Australia
  • 1992 K75s Hybrid, Lefaux, Vespa V twin.

Offline Past-my-Prime

  • ^ Proficient Motobricker
  • Posts: 240
Re: 4yr stored k75--prob?
« Reply #7 on: November 06, 2019, 08:28:32 PM »
Not to forget:

Oil/Filter
Brake Fluid flush
Coolant flush / refresh
Transmission Fluid
Final Drive Fluid
Driveshaft Spline Lube

None of these things takes too long. All together took me about two days as a DIY'er
  • North Shore of Lake Superior
  • BRICK: 1989 K75 RT - Rocinante; NONBRICK: 2007 F650 GS Dakar - not yet named

Offline The Mighty Gryphon

  • ^ Quintessential Motobricker
  • Posts: 5199
Re: 4yr stored k75--prob?
« Reply #8 on: November 07, 2019, 08:11:47 AM »
Don't be surprised if the rear master cylinder is whack.
  • In my garage in Marilla, NY
  • '94 K75RT Mystic Red, '91K100RS White/Blue, '89 K100RS Special edition White/Blue
Current:
'94 K75RT "Ilsa, She Wolf of the SS"
'91 K100RS "Moby Brick Too
'89 K100RS SE

Offline natalena

  • ^ SuperNatural Motobricker
  • Posts: 523
Re: 4yr stored k75--prob?
« Reply #9 on: December 02, 2019, 11:51:54 PM »
Great advice above. It's worth cleaning/checking all your light bulbs while deoxit'ing the plug connectors. It's easy and gives instant results and success that helps counterbalance any bumps in the rehab process. Good luck, you'll have fun, as these are great machines to work on. Cheers
  • East of Joshua Tree
  • 1987 K75s #0919
On Holy Quest seeking Techron equivalent for splines.

Online Martin

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Re: 4yr stored k75--prob?
« Reply #10 on: December 03, 2019, 12:10:17 AM »
Fuel pumps can be obtained from AliExpress they also have rear master cylinders.
See here http://www.motobrick.com/index.php/topic,10054.msg86054.html#msg86054
and here http://www.motobrick.com/index.php/topic,9364.msg116179.html#msg116179
Regards Martin.
  • North Lakes Queensland Australia
  • 1992 K75s Hybrid, Lefaux, Vespa V twin.

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