Tail chasing with old GS750ES- Elec. gremlins

[baz666]

Electrical or fuel related? Fuel or electrical? I got myself convinced that everything electrical checked out and the bike won't start no way no how, cranking like an sob with good spark but not a cough or sputter so I figured fuel, right?
Then while having the key turned to on I accidentally hit the turn signal switch and the 10A TURN SIGNAL fuse blew. Then I recalled this problem was beginning to happen just before putting the bike away last fall.

The other thing is, I found a thin oily substance, like hydraulic oil, on the fuse board and tracked it not to the turn signal fuse circuit which is second from the top on this bike, but to the top fuse circuit, which is for the headlight.
Is there something inside the fuse box that could be leaking causing a short in the system? I now recall the bike was blowing 10A turn signal fuses regularly after my neighbor and I changed the rear turn signals to tiny bullet signals.
I'm going to go over all the turn signal connections, front and back and return the stock rear turn signals to the bike but is there a way to test the fusebox? If it needs replacing, is it possible to wire-up in-line fuses with each circuit wire that goes into the fusebox so I don't have to go looking for a replacement?
I know I keep coming back with different problems, fuel then elec. - elec. then fuel - but I'm a slow learner so I appreciate your patience.
thanks,
baz

[BassCliff]

Hi,

For reference:

Fusebox Cleanup

Fuse Box Upgrade

I also think you need to take off the tank and seat, remove the headlight, and go through all the wiring and connectors looking for worn insulation, melted connectors, shorts, etc. Repair and replace whatever is necessary. Then we can move on from there. I know it's tedious but your bike will love you for it.


Thank you for your indulgence,

BassCliff

[cowboyup3371]

Okay, something happened to my post so let's try this again. When you replaced your turn signals, did they have a separate ground wire? I found when I replaced the ones I had with a stock set I will need to connect that up as well (old ones didn't have it). It's possible it might not be grounding correctly and blowing the fuse.

[baz666]

Thanks for the instructions.
I rigged up a little test light and plugged it into the fuse box rather than continually blowing fuses.
Too bad I can't figure out what the resulting tests mean exactly.
Maybe one of you folks can help me out with this:
With the key turned to the On position and the test light
plugged into the headlight fuse circuit, the light remains lit.
When the test light is plugged into the turn signal fuse circuit, the light also remains lit.
When the test light is plugged into the Ignition signal, the light comes on for a second then goes out.

Does this mean the headlight and turn signal are open circuits and thus continually shorting?
Does it also mean the Ignition circuit is okay since the light goes out?

I've checked and cleaned all four turn signal connections. The b/w power wire at the front left signal is strange. It comes out of the harness, has one brass wire plug, a b/w continues along and goes to a second brass wire plug. I don't see it on the wiring harness so I'm assuming a PO added it for extra lighting that's since been removed. Or does this extra plug have some purpose?

thanks in advance,
baz

[spyug]

First off there is no fluid of any kind in the fuse block so goodness knows what it is but you need to clean it out. Remove the block and gently pry it apart. Inside you will find several brass strips, running from the sides where the contacts are to the center where the fuses are. Depending what the goo is, it could be causing the short between two of these strips. Clean everything, dry it off and reassemble.

The big thing about old bike electronics is that the contacts and connectors corrode over time. This results in either resistance in the circuits causing voltage drops or(in the case of ground wires) poor or nonexistant grounding. Old wires are also brittle and break or the plastic cover wears off exposing the wire which can short on something. As an old guru on another board always used to say, "If a circuit doesn't work first check the ground".

To ensure good continuity in your circuits it is always a giood idea to clean all your contacts and especially the connectors. In some cases old connectors are so badly corroded or even melted they need to be replaced so you should pick up an electrical connector kit some shrink tubing, electrical tape and a soldering kit.

The most valuable tool in the electrical kit is the circuit test probe so you can trace live circuits. IMHO you can't work on circuits without it.

When working on the bikes electrics you ,of course, need a schematic to refer to so you should have a manual. Its hard to find your way if you don't have a map to refer to.Check Cliff's site if you don't own one.

Working with the electrics is not hard but at times it can be annoying when things don't make sense. Its a game of logic and you need to be methodical. Sometimes the manufacturer or PO makes it complicated by adding some wires that don't go to any device ( I suspect this is the case with the wire you describe and another reason to refer to a schematic).

If you are new to electrical stuff there is a fantastic book by Tracy Martin which is available through Chapters/Indigo for around $25 that covers everything you'll need to know. I heartily recommend it. http://www.tracyamartin.com/WebPages/MotorBook.html

So for now, dig up that schematic, get out your circuit tester and start to familiarize yourself with the wires and electical devices. Don't forget to cleanup that fuseblock and make sure all the contacts from the battery to the solenoid to the fuse block and beyond are clean and tight. Over time you will want to clean and or replace everything else.

There is a fair bit to do but take your time and do a bit here and there and you'll get it done.

Good luck,
spyug

[baz666]

Thanks again for all the help. I'll go over the wiring slowly and carefully.
I think I have a couple of different issues going on here, both elec. and fuel related. I have the wiring diagram and the factory manual, both printed from BikeCliff's site, and I have the multimeter ready, with a new battery in it, along with a new bike battery.
So I'll have to start at the beginning and check all connections and grounds, along with removing and thoroughly cleaning the carbs. I don't feel too bad and feel like I have some time since the weather's not great yet. I'd probably feel worse if it was sunny and warm out.
Well, wish me luck!
I'm sure you'll be hearing much more from me very soon!
thanks again,
baz