No power leaving starter relay

[Mtduncan]

I have a 79 gs1000 I picked up cheap. I’m going through the wiring trying to get it to turn over with the start button . I have put on a new starter relay I’ve got power on the switch wire and the one off the battery, cleaned start button also. It did not have a ground at the bracket for the relay I thought that may be my issue . When I try to ground the bracket to either the battery or a frame ground the red wire from the rectifier gets very hot and smokes. Also the top fuse in the box gets hot. I have went through and cleaned all the grounds I could find and still the same issue. Any ideas would be helpful thanks

[Cipher]

Wow my solenoid has no ground.
is this a dead used part? Internal short?

[Mtduncan]

Not a dead used part, I’ve bought 2 new and both have the same issue . Both new parts . The old relay had the same issue. Which is why I tried to ground the relay bracket to both the negative post on the battery and the frame . What other internal short could I have ?

[phydeauxmutt]

Is this a Suzuki solenoid? If yes, you should have the battery connected to one of the large posts, the starter to the other large post. The smaller post (might just be a wire) is what comes from your starter button. The solenoid is grounded through its case, but it's mounted to the battery box, which is rubber-mounted, so it requires a ground wire from one of the mounting screws to the chassis.

If it's NOT a Suzuki solenoid, does it have three electrical contacts or four? If it has three, it's just like the Suzuki solenoid. If it has four, there will be two large and two small posts. The large posts connect as above. One of the smaller posts will be connected to your starter button, the other one will be connected to a chasis ground.

[Mtduncan]

It’s a solenoid off eBay, only three contacts one for battery one for starter wire and the other is a yellow green wire that plugs right into the factory harness, I cleaned the ground at the battery box and had the same issue , so I tried to run a wire from one of the mounting bolts on the solenoid bracket to another known good ground and still getting the heat and smoke from the red wire out of the rectifier and the heat at the top fuse

[Gorminrider]

Disconnect the regulator,. Your bike can start and run for quite awhile with a good battery. Regulator is likely bad....indeed as mentioned, the only thing that (should) ground through the coil casing is the solenoid's coil....activated by the small wire. It's simple to test solenoid. Disconnect the Large wire from battery and apply + to the small wire-"Click, Click..." reconnect large wire do again-bike turns over whether key on (might start the bike) or key off( merely turns over)

[Mtduncan]

I unplugged the regulator that seemed to fix my smoking / heat issue . Still can’t get the solenoid to click . Tested the solenoid it works fine when just touching the bracket to negative battery post and switch wire ti positive . With everything bolted in where it should be I get about 11.2 volts to the switch wire when pressing the start button. Which is around 1 volt less than battery voltage .

[Gorminrider]

tested the solenoid it works fine when just touching the bracket to negative battery post and switch wire ti positive .

so problem is either the starter button at handlebar, the connection to that button or the + connection to the other wire that feeds that button...follow the yellow/green wire back to the starter button..
could be disconnected near the solenoid or the other end inside the inside the handlebar switch....Member DaveR here recently had similar with broken solder in there...

OR with all that ok (moving on to much the least likely...) the place the solenoid is bolted to that has no ground...easy to test so might as well cross it off the list-negatve Vmeter probe to that plate and positive Vmeter probe to "+ "on battery or the big bolt on the solenoid post that's so much nearer and just as "+" ...or use a 12v lightbulb with a wire to that + and bulb tip on plate ground-it'll light up if it's a good ground.

[Cipher]

https://gsarchive.bwringer.com/mtsac...S-L_Manual.pdf
pg 165
and 184
also might pull the headlamp and check for chafed wires.

[Mtduncan]

Thanks for the help fellas. After unplugging the red wire from the rectifier I checked and had no ground at the solenoid bracket . Added a temporary ground to get it to turn over. Makes a nasty sound behind the stator cover while engine is turning over but it does turn over. Thanks

[Cipher]

Seems your fun has just begun

[Gorminrider]

I checked and had no ground at the solenoid bracket . Added a temporary ground to get it to turn over

.aha. I guess it's not so uncommon...on my bikes with the plastic airbox behind the solenoid-regulator mounting plate can make it confusing but one or two of the bolts holding the plate against it DO thread through lugs welded to the frame. Some here use a lightly longer bolt, attach all their grounds to it with a nice thick wire to the negative post of the battery...not elegant but it surely leaves no doubt.

Likely that hurt your regulator too as its ground wire is commonly attached to the same plate. ( the casing of the regulator is NOT grounded-it needs the wire coming out of it to be grounded)