Gen light off

[dewane]

I have an '83 R65. Got a new dynacoil to replace the cracked original coil. Had the gen light go on dimly, so replaced the diode board and checked all wires and shot some contact cleaner in the connections.

That worked for all of 100 miles. Now the gen light doesn't go on when I turn on the key. Can you let me know of likely culprits, and ways to check? I'm sure this is here somewhere.

Thanks

[Bob_Roller]

Seeing as how you were just in the area doing some work, I would go back and recheck the connections, something may have just become disconnected.

If everything checks out, then you need to do a little trouble shooting .

First, I would check the light bulb, they don't go bad too often, but not difficult to get to, unless you have a fairing, it's what is commonly called a 'wedge' type bulb, it sits in a socket, doesn't lock into the holder, not a great design for this application, bulb may may come out of it's holder.

The bulb is a common SAE 168 or 194, available at most auto parts stores, don't get an LED replacement bulb, the charging system won't work correctly with one installed .

Second place to check, is the alternator rotor, an 'open' rotor will cause the 'GEN' light not to come on .

[donbmw]

Everytime on I have had the Gen light is dim it has been brushes needed replacing or not contacting or bad contections with the voltage regulator harness or some of the contectors at the alternator.

Don

[nhmaf]

Along with the possibility of sketchy connections on the other side of the bulb (going to voltage regulator and from there down to the alternator) you could also have a corroded contact in your ignition key switch or on the terminal from that switch that feeds the bulb/v-reg/alternator branche of the circuit.

[montmil]

... don't get an LED replacement bulb, the charging system won't work correctly with one installed.

An Led GEN light most certainly will work if you also fit the Generator Light Auxiliary Circuit.

http://www.motoelekt.com/genlightacc.htm

I have this setup on my 1981 R65 and it functions just fine.

Monte

[Semper Gumby]

... don't get an LED replacement bulb, the charging system won't work correctly with one installed.

An Led GEN light most certainly will work if you also fit the Generator Light Auxiliary Circuit.

http://www.motoelekt.com/genlightacc.htm

I have this setup on my 1981 R65 and it functions just fine.

Monte

Now that is an idea!  What are the part numbers for the LED bulbs?  I hate diging into that instrument.

[Bob_Roller]

If they are available at your local auto parts store, they are the same numbers as the incandescent bulbs, 168, 194 .

[montmil]

Radio Shack gots 'em.



Monte

[Bob_Roller]

I think Bill was looking for a direct replacement bulb .

[montmil]

I think Bill was looking for a direct replacement bulb .

:-/

[Bob_Roller]

I've tried the LED replacement bulbs in the instrument background lighting, high beam indication and turn directional indication, they were not suitable for any of the uses on an R65, just too dim compared to an incandescent bulb .

[dewane]

Hey guys, if we could get back to my problems, which naturally are the most important things...heh

The gen light is not dim, it is off. I pulled the tank (again) and checked the wiring (again). all wiring in the alternator area there looks fine. Pulled the diode board (again) and checked the wiring there.

The light is fine, I swapped the gen light with the oil light and that is not the problem.

Can you let me know how to do a continuity test for the alternator?

I'm normally a pretty patient guy when it comes to wrenching, but looking at the wiring job that somebody did under the tank just makes me mad. They routed the throttle cable like a preschooler would do, and wires go every which way with no sense to the routing they would take as a matter of common sense.

I had a slash 5 and the alternator went out and I swore off German bikes for a while. If this one is out, it's "cut bait" time.

Then again, I think I'm feeling like my friend says when he's working on something and gets a problem: "you want to buy this truck for 10 bucks?" "why what's wrong with it?" "this bolt won't go in right".

[Bob_Roller]

To check the continuity of the rotor with it still installed, you need to raise the brushes and place a piece of paper between the brushes and the slip rings .

With that done, you need to place the test leads from a multimeter one on each slip ring, with the meter set to the ohms position a good rotor should read a couple of ohms, can't remember the exact value right now .

A faulty rotor would read 'open', no continuity .

We were just killing time until you got back !! [smiley=1drink.gif]

[dewane]

Hey, thanks!

I blew a fuse in my multitester. So I just shorted those two brass rings, per another thread I read. And, the gen light goes on.

Would that indicate a bad rotor as well? I need to go to the store and get a fuse anyhow

[Bob_Roller]

When you touch a metal object between the slip rings with the key in the on or run position, you are testing the wires from the brushes all the way up to the light bulb .

Seeing as how the light goes on when the test is preformed, the wiring is good .

So now you need to check just the rotor, that's why you need to insulate the brushes from the slip rings .