Removing a generator

[1955fle]

I found the problem with the GEN light staying on with my '55 FL. It is an original 3-brush generator. I removed the end cap and wiggled the brushes to see if they were sticking. Closed it back up and the bike started first kick. The GEN light goes out. All fixed great. But no!! If I rev the engine the light comes on, and goes off, and comes on, and goes off. I also took the regulator and cleaned the points inside. So my guess is that I need new brushes. I also took a meeter reading. With the light on 5.65V with the light off 7.25 V. Does this make sense?

So how do I remove the generator? Do I need to remove the right side case cover to remove it? Where is the best place to get it rebuilt? Any help will be appreciated.

-Carl

[NightShift]

Dear Carl,
Please tell me you have the service manual?

"Spectful always,

[steve_wood]

Carl:

You might be able to change the brushes without removing the generator. Remove the end cover and see if you can get at them. You might need to put the bike on a lift to get at the bottom one.

Try that first....

[fourthgear]

Yes get a shop manual & don't forget to clean the commutator , I know I didn't spell that right , its what the brushes ride on . if there is debris between , on the insulators, it will cause all kinds of problems , not to mention grease or oil on it. Clean the contact area on it too , that too will cause problems( scotch brite pad will work ) . There are other things to check, that would be a start.

[1955fle]

Thanks for the reply. I do have a service manual and have read through the generator area. I think I understand what to do, but I am not that up on the electrical aspects as I should be. So some of the terms are throwing me. Also the manual I have came from Antique Cycle Supply and the photos are not the best.

When I took the end cap of there was some oil coating the inside of the cover. Does that mean there is a seal leaking?

To check the brushes do I remove the outer grease retainer? It looks like one of the brushes is under that. Do I need to remove the armature to get to the other 2 brushes?

Thanks for the help.

[Hauula Pan]

It is easy to remove the gen. If you have a strap over it loosen it there are 2 screws in the timing cover that actually mount the gen. One at 11 o'clock and one at about 5 o'clock, disconnect the 2 wires and that's it, it will slide right out. WARNING !!! Do not use after market Taiwan relay - They are all junk ! Every one of them will stick and some are even wound backwards. Pay the extra and get a Delco. The voltage readings are about right, you adjust the output by moving the 3rd brush. The 6 volt system is pretty basic, just the battery, gen. & relay, the relay cuts in or out as the load demands. The one drawback is that if you do a lot of stop & go and idling with lights on you can't keep the rpm's up and the gen. can't keep up with the load draw and gharge the battery too, so it runs down. The problem with the cheap relays is they stick and when you shut the bike off the circuit is still made and the battery runs down. For a long time before I figured it out I used to run an in-line fuse and just disconnect the battery so if the relay got stuck it wouldn't drain the battery. I now use a good Delco relay. I still have a cut off switch on my pos. bat. lead that I turn off just in case. Some people used to remove the third brush and rewire the gen to run without it, this basically keeps the output high enough to keep the relay closed and constantly charge the battery, the drawback is on a long highway run you can easily over charge & cook it. These are reasons so many have switched to 12 volt systems. But if you take care of them the 6-volt system is just fine.

[1955fle]

Hauula, thank you for the reply. I do have a Delco relay which is in good condition. I do believe that I removed the generator about 15 years ago and replaced the brushes, but I haven't touched it in a long time so of course I forgot everything. This weekend I will remove the generator and disassemble it and clean everything. Should be an exciting journey. I will let you know how it goes.

-Carl

[Hauula Pan]

One more thing you should check is the gap settings in your relay, they control Everything and need to be exact.

[1955fle]

Well I remover the generator and it was completely coated in oil. I cleaned everything, made a new gasket and will be getting it back together tonight. I will let you know the results. Also thanks for the tip on the gap for the relay. I am sure that info in in the service manual. -Carl

[Hauula Pan]

Sounds like you have a handle on things. The info. on the relay gaps is on page 191 of the Panhead Service Manual. When gen. volts exceed bat. volts about 6.3-6.8 the relay closes the gen. to battery circuit and the light goes out, usually about 20mph. The relay gaps are .015 for the armature gap, .020 for the main gap & .020 for the signal light gap. Remember when you put the gen. back in the bike check your output and adjust it by shifting the 3rd brush.

[steve_wood]

Carl:

As long as you have it off the bike, you should change the right side bearing (part number 9007), oil seal (30145-46) and left side bearing (9005). You can replace these with modern equivalents. If you use a sealed bearing instead of the stock ball bearing you'll get even better protection from the oil in the cam chest.

Does your unit have the oil deflector (31035-31)? If not, you might want to get one....

[1955fle]

Thanks for all of the great help with this. Here is where I stand. Installed the generator after cleaning and adjuster the relay points according to the manual. This is the current results; bike started, switch at first position, gen light on, voltage reading from terminal closest to the engine .238.

Set switch to second position headlight on, gen light goes out, voltage reading from terminal closest to the engine 6.58. It never did this before. Does this sound correct? Should I look into getting a new relay?

Also I am not sure how to check amp rating with my meter, any thoughts?

-Carl

[awander]

From the way it is acting, it sounds as if the generator is not set up properly.

In a 3-brush generator, the 3rd brush controls how much "ground" one of the field coils gets. This is how you set the current output of the generator.

When you switch the lights on, the 2nd field coil is energized, and causes extra current output to cover the supply needed for the lights.

I would check the 3rd brush setting.

[1955fle]

Thanks for the reply. I went through the manual regarding setting up the 3rd brush and it is not clear to me how to do it. I understand how to move the 3rd brush, but not sure how to measure the results. What is the best way to proceed?

[awander]

According to the manual, you need to measure the current flowing into teh battery, using a 0-15A ammeter, and adjust the brush fo rthe correct amount of current.