Topic: CB 650 - Fuse blows when installing new solenoid

[Flying Tiger]

Hello, .. How about this? I picked up a low mileage CB 650, that can be started only by jumping across the solenoid. The bike does run, a slight click is heard when pressing the starter button, .. but, no turning. I tried to "repair" the original solenoid, but noo way .. So, what I have now, is a crap solenoid installed necessary to permit any electrical function. I just have to jump across the solenoid terminal. And away I can go ..

OK, .. I get a price for a new one of $95 at the Honda shop, and I decide to go with an aftermarket one instead advertised as "New Honda CB650 CB700 650 700 Nighthawk Starter Relay". First, because the plug-in connection is placed on the opposite side (new) from the original, I hooked it up wrong, (battery to motor, and the other way around) with the obvious non-result, .. finding my error, I hooked it up the right way, hook the battery again, .. and the fuse blows, .. consistently, .. I thought I've ruined the solenoid, .. reordered another, hooking it up right this time, with the same results, blown fuse, immediately. The connector plug can only be put in, one way, as alot of you probably know.

hmm, .. mind you, all the electrics work fine. The bike is running fairly well. I checked the wiring diagram and found the wire from the starter button to the solenoid, .. and checked it with a multimeter, .. and there's no current that goes through until the button is pressed. If the ignition is on, and in neutral, the neutral light and oil pressure light get a little brighter, when I press the starter button. (No fuse blowing, here)

Now, I suppose there might be something wrong with this aftermarket solenoid's wiring configuration of the connector plug, .. Although, a person would think they would have had complaints, by now.. I have found another used solenoid on Ebay, .. (the money order seems to be hung up, between here and Canada, somewhere) .. and I'm very curious to see if that makes the difference, .. or if the learned readers here might know of something else that I have to do, to fix this problem? .. The answer is worth several beers, to me .. haha ..

Thanks for your time ..

Ken

[oldbiker]

Hi Ken,
 first off, you will understand that it is VERY difficult to diagnose a problem from your description but here goes!
 I have the wiring diagram of your starter solenoil in front of me and if you have an electric meter you can make certain tests before you try to fit it on the bike. First, there should be two very large heavy contacts which will carry the heavy current taken by the starter motor. With the meter find which of these connects to the 30 amp main fuse. This is the terminal which connects directly to the battery. The other heavy contact will go directly to the starter motor.
 You are now left with three smaller contacts. Use the meter to find which of these connects to the main fuse. This one should connect to the red and the red/white wires which feed 12volts to the ignition switch etc.  There are now two wires left which are connections for the operating coil and these are connected to the green/brown and the orange/white wires. (which is which is not vital) If you don't have a meter you can use a spare bulb and a battery to rig a continuity tester. Hope this is a help and come back if you still have trouble.

[Flying Tiger]

Sir, .. I should have stated that this is a '81 CB 650

Well, of the solenoid's 2 large leads, ... one is marked with a red dot, which goes to the battery, (according to the directions I got)There's also a "B" there, while the other side has a "M" (for motor, I suppose) .. The directions on how to hook it up are plain enough, .. like I said, I hooked the 2 large leads in reverse, at first.

Now as far as the other smaller connections I have 4, not 3 leads are in a plug-in plastic connector to the side of the solenoid, ... and there's no choice in how a person plugs it together, .. it will only allow you to do it one way. My wiring diagram concurs with what I found to be the starter button wire, .. a red/yellow wire, the one I mentioned before, that I tested with a mutimeter.

So, to put this all in a shorter way, .. I originally could start the bike only with jumping across the solenoid, .. fine, order a new solenoid and this burns out fuses, .. with everything turned off.

Now, what I'm doing now to keep the bike rolling, is to put the old bad solenoid back on and jump the solenoid, .. the bike starts right up, and the battery holds the charge for days. Soo, again .. I'm asking if anyone has the scoop on this problem, ..

Thanks again ..

Ken

[oldbiker]

Ken,
       you say the new solenoid burns out fuses with everything turned off. Can I suggest you try the old trick of replacing the fuse with a spare 12v bulb for testing.
   This will light up because of the fault but will protect the wiring and the battery while you isolate which wire is causing the short circuit. You may now move wires about or disconnect individual wires until you find the one which causes the bulb to go out. Once you have found this you are half way to curing the problem.

[bryanj]

Honda changed the way the solenoid was wired from a ground at the bars to a power from the bars system so its no good just "plugging" in the wires you have to sort out which is which on the solenoid and in the loom

[Flying Tiger]

Old Timer, Bryan ..

Happy days, ..

I switched around the wiring on the connector, which you eluded to, Byran .. That solved the problem, .. I'm pretty sure no one appreciates a working electric start button like I do ..
 
Thanks for the replys, ..

Ken