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1994 K75, Starting, running, and charge light issue

heejrbmw

New member
I have noticed the last few times I started my K75 the alternator light stayed on very dimly after the engine was running. Every time, it went out in a few moments.

Yesterday, after the engine was warm,
1) I attempted to crank engine and the fully bright oil and alternator light went to half bright and the engine did not start.
2) I let off the starter and tried again. The lights this time were full bright, and the engine started. However, it quickly died.
3) I tried to start again, and same scenario as (1).
4) Once again I pressed starter, and engine started normally and appeared to be OK. However, even with mid-range choke/mid level high idle engaged, at the first traffic light, the engine suddenly turned off.
5) It started again normally.

In the evening when I left work,
6) I pressed the starter, and the lights went dim again as in (1). I let off the starter.
7) I tried again, and it sounded like the starter solenoid hung (sounded like a loud crack or pop). I thought something broke!
8) I tried again, and everything seemed normal.

I rode ten miles to a meeting and it ran fine.

When I left the meeting two hours later, I experienced 1) above and then 5). The engine seemed to run flawlessly for the 25 mile trip home.

The battery appears to be charged and is kept on a Battery Tender Jr. most of the time, although I understand from all I'm reading on the forum that it could still be bad. I don't know the age of the battery. It was in the bike when I bought it, so it is at least 4 years old. It is a WestCo.

I suppose I should go ahead and change the battery, but I would like to know that my problem is the battery.

Does this sound like a weak battery / soon to stick solenoid issue? Or something different?

Thanks for any help!
Ed
 
Ed,

The battery's a question; without a load test, it'll remain so, and that uncertainty complicates the diagnosis of whatever else might ail the bike. I'll observe that it's four years old, and getting to or past the point where failure is likely - DonE would say it owes you nothing at this point. I'd replace it.

The rest of the symptoms could be the result of a bad battery, or of bad connections (battery cables, both ends of both cables), or of a dirty ignition switch. Replace the battery, and clean the connections, and see what happens.
 
When my WestCo died in my K75RT it exhibited the following symptoms:
- key to on, everything lights up as normal.
- hit starter, lights go out, starter does not engage, rpm meter slowly goes up to 4k and slowly returns to zero.

Echoing David, were I you I'd be looking at the ground wire to make sure you've the improved beefier version and that it is not loose, corroded or the eyelet broken. I'd also look at cleaning the starter and ignition switch, tutorials on the IBMWR site here:
http://www.ibmwr.org/ktech.shtml
 
Ed,

The battery's a question; without a load test, it'll remain so.

I had the battery load tested at two locations today. At the first, my WestCo battery reported 12.88 volts and 283 CCA. At the second location the report was 12.79 volts and 288 CCA. I do not know what the CCA is supposed to be, but I have seen new batteries advertised with more and with fewer. There is a number stamped in the top of my battery. It is 051117F. I wonder if that means November 17, 2005? Anyone know? If it does, that means it is 7.5 years old. The number on the battery is 12V20P. I'm relatively sure it is an AGM. I know it is lead-acid.

I see the WestCo battery was made in Vietnam. I might have a problem with buying one for that reason. Oh well! Old wounds!

I will begin at the starter I suppose. Any other ideas welcome!
Ed
 
Clean the ground contacts. Maybe upgrade to a heavier ground cable. FWIW I'd clean the starter too. Easiest way to find the actual problem is to remove the simple and obvious possibilities first.
 
If you have a voltmeter, measure the voltage at the battery terminals. Then, with the key and kill switch on, take the positive probe of the voltmeter and put it into one of the two open spaces on the back of the top fuse in the fuse block and put the negative probe on the bolt where the ground wire bolts to the transmission. If that voltage is more than a half a volt less than the battery voltage, it indicates that the ignition switch contacts are probably dirty. But if the voltages are the same, it does not necessarily mean that they are clean. This is just a quick and easy way to confirm if they are dirty, not to prove that they are clean.

I've had them with almost 5 volts difference and had similar problems and cleaning the ignition switch fixed the problem.


:dance:dance:dance
 
Just a reminder that a lot of times when these problems manifest themselves they are the result of several things which together become quite noticeable. Doing the ignition switch and starter is an easy afternoon job, and while you are in there the ground cable is easy to check.
 
TED;880366 Doing the ignition switch and starter is an easy afternoon job said:
I removed the starter and did a full cleaning and it looks like new inside. It was dirty, and the brushes had what I would consider a normal amount of brush residue on the rotor. I shined it and reassembled. It works fine. I took the ignition switch out and did a full cleaning. There was some buildup on the contacts, but it did not look too serious. I removed all the residue and shined the contacts.

Reassembled everything and cranked engine with no problem. I have started the engine about 10 times, and so far so good. I will have to wait now and see if the problem reappears. Perhaps one or both actions cured the problem. I will probably go ahead and order a new battery at the first hint of any remaining problem. I have searched the Internet to try to find any reference to a date code on the WestCo battery, but so far no reference found. I feel almost certain that the number I found stamped into the top of the battery is a date code. If it is, it has been almost 8 years since it was manufactured.

I also checked the ground wire. It is beefy and the ends are clean and shiny.

Gentlemen, thanks for help and references/links. The links were very helpful for the starter and ignition switch rehab.

Ed
 
When I have had to clean the ignition switch, it LOOKED fine inside, but the cleaning fixed the problem.



:dance:dance:dance
 
I am happy to report that I have not had a single starting, charging, or running issue since performing the recommended service to the ignition switch and starter. I have started the engine about twenty times, and so far, everything looks good.

Thanks for all the good advice and instructions!

Ed
 
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