1 K100 Cooling Fan Problem Wed Dec 29, 2010 9:10 am
MGM
active member
Need a bit of advice
I’ve purchased a 1985 K100RS for a charity bike ride from London to the South of France (and hopefully back). You know the type of thing, max budget £500, challenges along way etc.
Bike had been standing unloved outside under a sheet for a couple of years, a lot of TLC it now runs.
I’ve found the info on this site excellent and could not have got the old girl running again without it, so thanks to all who contribute.
Problem is when testing at idle I noticed that I had never seen the cooling fan running although never ran her for very long. Not wanting to cook her I followed the test procedures that Jeff posted but have come to a dead end.
Ran the bike at idle for 20min fan didn’t come on.
It was about 5 degC in the garage but radiator and hoses to hot to touch.
Left her overnight to cool down. It’s just above freezing today,
Tested the fan by jumping relay connections 15 and A2, fan ran ok.
Checked resistance between E and 9 but appeared to get an open circuit
Disconnected temperature sensor checked resistance across terminals, got (9.7K),
Jumped sensor connector - fan didn’t run
Cleaned all connections, no joy
Checked continuity between 9 and sensor OK
Checked continuity between sensor and connection 10 on the EFI female connector - OK
Checked resistance EFI connector 10 to ground (4.8K)
Checked overheat light - OK
Resistances seem high but it was cold overnight, but can’t explain why no resistance between E & 9 and why jumping sensor connector didn’t work
Any suggestions?
I’ve purchased a 1985 K100RS for a charity bike ride from London to the South of France (and hopefully back). You know the type of thing, max budget £500, challenges along way etc.
Bike had been standing unloved outside under a sheet for a couple of years, a lot of TLC it now runs.
I’ve found the info on this site excellent and could not have got the old girl running again without it, so thanks to all who contribute.
Problem is when testing at idle I noticed that I had never seen the cooling fan running although never ran her for very long. Not wanting to cook her I followed the test procedures that Jeff posted but have come to a dead end.
Ran the bike at idle for 20min fan didn’t come on.
It was about 5 degC in the garage but radiator and hoses to hot to touch.
Left her overnight to cool down. It’s just above freezing today,
Tested the fan by jumping relay connections 15 and A2, fan ran ok.
Checked resistance between E and 9 but appeared to get an open circuit
Disconnected temperature sensor checked resistance across terminals, got (9.7K),
Jumped sensor connector - fan didn’t run
Cleaned all connections, no joy
Checked continuity between 9 and sensor OK
Checked continuity between sensor and connection 10 on the EFI female connector - OK
Checked resistance EFI connector 10 to ground (4.8K)
Checked overheat light - OK
Resistances seem high but it was cold overnight, but can’t explain why no resistance between E & 9 and why jumping sensor connector didn’t work
Any suggestions?