Blowing fuses upon install with key in the "off" position

[Lazer400]

It does seem odd that the TCI would just go out. Especially since it was working a week ago. The kill switch is working correctly as is the fuse. I am getting power everywhere it needs to be. The only thing I can think of is the connection to the pick up from the TCI.

 

[Lazer400]

Connection to the pick ups is good. I re-tested the coil windings and read 3.7 primary and 17.5 secondary. This is abnormal, yes?? Would this cause me to have no spark??
Checked over all of the connections again and everything has power, a full 12v at that.
I will draw up the diagram that I am using and post it tomorrow. Maybe that will help.
I will say though that I officially have no fuse blowing anymore, that is way cool.

 

[drewpy]

don't run the TCI without a spark plug earthed. the TCI will fry

 

[Lazer400]

That is good to know.

Okay so, I rewired today. Made a few new connections even though they looked okay. I did in fact have a bad ground connection. Wrong wire gauge in clip connecter.

I turned it over and after a few kicks I got one loud backfire. The tank was off, I sprayed some starting fluid into the cone filters and kicked maybe 5 times. All I got was the loud pop. Could a dry carb with only starting fluid do this?

I haven't tried again in fear that I will blow the carb boots to shit.
I suppose I will though tonight. Maybe with the tank on and real gas instead of fluid.

 

[drewpy]

it will only blow the carb off

tip a bit of fuel inside the spark holes and try again. you could be 180' out, swap coil feeds

 

[Lazer400]

Haven't blown em off yet.
Also, I have pods instead of stock intake. Not sure if the jetting was done to compensate but I would imagine so since it was running just fine before I started "tinkering".
I will check the coil leads. As it is now I think I have the gray going to the drivers left side coil.
I did have some light intake backfire before, but only when the electric start was used and never when kicked. Once it was warm it would start either way with no issues.

After putting the gas tank back on, There have been a few very subtle misfires out of the pods but nothing like the first with just the starting fluid.
Still doesn't want to fire. After fixing the ground fault I have a nice fat blue spark!
I installed new bp7es plugs, the PO was running Bosch R3's? I tried putting the r3's back in thinking that maybe that would be the difference but still nothing.

How likely is it to blow a piston upon starting the bike??
Could the alternator wiring play a role in this?

I will try a little gas down the plug holes. If it fires then I suppose the carbs need a cleaning or there is a delivery issue of some sort.

I still want to say that it's gotta be related to my wiring.

The diagram I am using has the black from the alternator grounded. In my stock diagram it shows the same B running through the connector to Brown which is hot and then G running to the V. Reg. could it work both ways??

I'm going to post some pics of it soon. While dealing with all of this crap I have also been quite busy making it look good too!

Thanks again everyone!

 

[Drewcifer]

Lazer any updates?

 

[Lazer400]

Hey, sorry for the delay I have been without internet.

I am happy to report that I am back in business.
I switched coil wires and after two kicks, it fired right up!

I want to note here that my bike is a 1980 xs400G
the Haynes manual wiring diagram for the G and SG models shows gray to the left and orange to the right. This is incorrect. It should be gray to the right and orange to the left. This should be correct for the 80 and 81 models with the TCI.

I have been out riding the last few days and it feels great!
All of my wiring is good, charging system is working flawlessly and no more backfires.

Here is the wiring diagram that I created.
If anyone has any questions let me know.
Some of the wiring is different for other models.
Mainly, the field coil and the ign coils.
Some models have the Black from the field coil wired to ground but the TCI models have the Black wired to hot.
Also, like I have stated above the 80 and 81 with TCI are gray on the right, orange on the left.
Let me know if you have any other questions, hopefully the colors are straight forward.

 

[Lazer400]

Also, I will get some pics up ASAP. I've been very busy.

 

[Lazer400]

Should I post pics and build stuff here or start a new thread????