Zener Diode in ignition?
 

Hello all! It's my fisrt post here, so be gentle! :p

I've bought a crashed VTR 1000f engine to use in a kit-kart, and I've got all the assembly and everything was working fine before the crash (duuhhh...).

The problem is, after checking and rechecking everything, The engine simply wont start or spark.

I don't have the ignition switch with the key, that stayed in the wreck, and I've read about a Zener Diode in some Hondas that "say" to the ECU that the bike isn't stollen. Could that be the issue here? Can't I just hot-wire the ignition?

The kick-stand is not the problem, and the starter engine rotates with direct conection at the relay. But the spark just doesn't come.

I'm guessing its something in the ignition, but can anyone help me out?

Thanks in advance,

Miguel Pereira
Portugal

BTW, here is a photo of the kart frame where the engine will be and the engine itself:

Attachment 23966

Attachment 23967

Kick stand is bypassed? How about clutch switch (or be sure it's in neutral).

Never heard of zener diode. How are the fuses in the box/ separate main fuse?

Your TPS isn't hooked up on your carbs... shouldn't matter for starting I don't think, but i'm not positive of that.

The fuses were all replaced. The kick stand is still pluged (will bypass afterward, obviously).

The TPS could be... Didn't remembered that one... Will try, thanks!

BTW, the bike was 98-99, not really sure. Don't know if matters.

As the engine is from an early VTR1000F it won't have the HISS (Honda Ignition Security System) as fitted to >2001 VTRs

Good luck on your buggy buggy

Keep the airbox and airfilter on as the engine will run shit without it - also did it come with radiators, R/R and all the gubbins etc. to allow the engine to run.

Are you sure the engine isn't from a stolen bike? http://www.vtr1000.org/phpBB3/images/smilies/eek.gif

I'm sure since I was the one that took the engine out of the wrecks in a certified wreck center. I have the papers to prove it as I plan the have the kart "legal" later on.

The ignition switch was partially destroyed in the yoke lock, and I didn't plan to use it so I just cut it. Just later I thought it could be from some kind of security system that my engine was not firing and I read about zener diode in honda's.

But you say that the VTR has no such system in these years?

EDIT: The radiators were damaged, I have a big one that I'll use, but that does not prevent the engine from firing. I have everything that I need for the engine to be properly used, I'm just having some kind of eletric problem. Does the fuel pump need to be "found" by the ECU?

No fuel pump; it's gravity fed. You said you're getting no spark? You have a lot of wires, I'd really make sure all the grounds are connected.

And did you check the clutch switch?

You can run w/out cooling system, won't run very well once the bike heats up for various reasons though, and damaging if you run it for a long time.

I have lot's of wires, and I'll double check if all of them are correct, but I think I'm no missing any. The clutch and the kick-start are correct. The TPS is on the carbs and the fuses are all new.

I'll have a cooling system, just not the stock one. I have a better one to use on the side. I just don't need it right away, I just want to fire the engine to begin the intallation on the frame.

What could it be? Can I just hot-wire the ignition or could it be something there?

Tweet's scanned in some color diagrams, downloadable here:

*Tweety's Wild Thinking

And not to make any assumptions: your kill switch is off, right?

If the kill switch is set to run, or bypassed, then look at the starter relay. It has a 30 amp main fuse that is completely separate from the fuse block.

All 3 ignition switch wires can be connected together, but the Blue/Orange wire only feeds the radiator fan motor.

The kill switch is not the problem, it was also destroyed but I've tryed with the wire on and off, and I've changed the 30amp main fuse.

The 3 ignition wires are all connected, even if the radiator fan is not needed for firing the engine (I don't have the fan).

Most likelly I'm just missing a ground somewhere, or something, but where?

Thanks for all the help guys. Eventually I'll find the problem...
I'm using a new battery.

Any more sugestions?

Thank you all for the help, but it turned out the problem was a missing "diode" in the fuse box, that I didn't even knew existed.

Those ****** at the wreck center took the diode from the fuse box just because...

Anyway, now the engine is firing and working as is should. The project can continue!

If you haven't already, download the service manual, it's linked in a post somewhere, just search, and it's easy to find... Get's you both a wiring diagram and general tips...

Hey miguel, post up some utube videos of your buggy when its running! (& post the links on here)

Oh, I have the manual for long now, but never ever thought this would be the problem.

The problem is that, because of the accident, most of the cables were all tangled and some were destroyed, so virtually could be anything wrong. It took us some hours to find the problem, and I can't thank enough Tweety's diagram, since it was from the diagram we got to the biggest problem (the minor problem were just some cable baddly connected).

And yes, when the project is more advanced I can post some videos of the mean machine. But most likelly I'll pop up before for the tuning of the engine! ;)

thank you guys

You gonna tease us or tell us what it ended up being?!

I already said some posts before.

Some *****r decided to remove the black diode from the fuse box. I didn't even knew there was a diode there. And its needed for the neutral switch circuit. I checked all the fuses, but the "slot" for the diode I thought it was for the replacement fuse and not another thing that was supposed to be there. I'm more used to yamaha engines.

Anyway, its fixed now! ;)