Author Topic: T3 Wiring  (Read 4587 times)

Offline ctk111

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T3 Wiring
« on: June 17, 2016, 04:44:51 PM »
I'm sorting out this T3 I recently purchased and am curious about a few wiring issues.  First, either it was a police bike or the owner before the previous set it up to look like one.  It had a few spotlights on the front and 4 lights on the rear.  I removed the front spots and the 2 larger ones on the rear, so that the only thing remaining are front and rear turn signals.

The left side turn signals work, but the right don't.  Where should I begin trouble shooting this?  Near the fuse box is a turn signal box (it's the silver box in the photo).  This thing is really hot to the touch.  Is this normal?  You can see plastic around the ends are melting.  I could smell wax melting while I was testing the signals.

Also very hot are the wires leading the starter, lights, etc. on the handle bars.  Is this normal as well?  I just don't know enough about electrics and this seems concerning.

 

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'73 Eldorado
'77 T3
Then
'66 Honda Dream
'74 Honda CB750

Offline rodekyll

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Re: T3 Wiring
« Reply #1 on: June 17, 2016, 04:50:04 PM »
NOTHING in your wiring should feel hot to the touch.  NOTHING.  You have a situation there that needs immediate attention -- there is something very wrong there.  I'd call in someone who knows what they're looking at if you don't, and I'd do it before doing anything else except disconnecting the battery.  You could burn that puppy to the ground.  . . .

Moto

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Re: T3 Wiring
« Reply #2 on: June 17, 2016, 04:59:49 PM »
You could burn that puppy to the ground.  . . .
I agree.

You'll need someone who can look at the wiring you have and figure it out. Though there are wiring diagrams available, we can't tell what the previous owner did to change things, so advice from the internet will be tricky.

Offline Rich A

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Re: T3 Wiring
« Reply #3 on: June 17, 2016, 05:03:43 PM »
You would likely save yourself a lot of headaches, cursing, etc. if you got one of Greg Bender's wiring harnesses:

http://www.thisoldtractor.com/for_sale_wiring_harness_tonti_850_t3.html

Rich A

Offline ctk111

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Re: T3 Wiring
« Reply #4 on: June 17, 2016, 06:09:58 PM »
OK, thanks for the input.  I'll see if I can work with someone locally and explore purchasing the wiring harness as another option.
Now
'73 Eldorado
'77 T3
Then
'66 Honda Dream
'74 Honda CB750

Offline fotoguzzi

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Re: T3 Wiring
« Reply #5 on: June 17, 2016, 06:25:40 PM »
spend money for new harness, save headaches and problems later.
MINNEAPOLIS, MN

Offline rodekyll

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Re: T3 Wiring
« Reply #6 on: June 17, 2016, 07:00:57 PM »
I'll go along with the replacement option as the way to fix it independently, quickly, completely, and cost effectively.  If you are not comfortable attacking large scale wiring disasters, it cuts to the chase.  Then you don't need to be an expert.  You just drape the new harness alongside the old one, move the connectors over one at a time, remove the old one, and zip tie the new one in place.  As long as you don't disconnect more than one wire at a time, you don't need to know anything about electricity.  Then if anything is still hot we can look at that device.

But please disconnect the ground side of the battery right now, before something bad happens.  This bike is not a runner until the problem is fixed, so you don't need it connected.

Offline acogoff

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Re: T3 Wiring
« Reply #7 on: June 17, 2016, 07:19:34 PM »
     My signals have only one wire and rely on the stalk being grounded to work, so I ran a couple of ground wires with a ring under each stalk retaining nut. Not sure if yours is the same though as mine has original set up for 1977.
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Offline ctk111

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Re: T3 Wiring
« Reply #8 on: June 17, 2016, 07:26:49 PM »
Ok, so buying the wiring harness should fix the situation?  If that's the case then I'll give it a go on my own first.  I'm just concerned the previous owner mucked it up so much that it won't be as simple as moving one connector at a time.  I guess I won't know until I try though.  Thanks for the advice.  Very helpful.
Now
'73 Eldorado
'77 T3
Then
'66 Honda Dream
'74 Honda CB750

Offline ctk111

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Re: T3 Wiring
« Reply #9 on: June 17, 2016, 07:28:26 PM »
     My signals have only one wire and rely on the stalk being grounded to work, so I ran a couple of ground wires with a ring under each stalk retaining nut. Not sure if yours is the same though as mine has original set up for 1977.

Some after market signals on there now.  Want to change them eventually.
Now
'73 Eldorado
'77 T3
Then
'66 Honda Dream
'74 Honda CB750

Offline rodekyll

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Re: T3 Wiring
« Reply #10 on: June 17, 2016, 07:37:50 PM »
No, this does not guarantee to cure all your wiring woes.  You could still have switches that need overhauling, high resistance at fuse contacts, bad single-wire-frame-ground devices, etc.  But without a doubt it's the place to start as it will cure 40 years of main harness abuse without having to be an expert in guzzi wiring.  Without a solid baseline at the harness level the remainder can't be tested.  And there's a (pulling a random but realistic number out of a handy orifice) 90% chance that yes, it will fix everything.

Offline ctk111

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Re: T3 Wiring
« Reply #11 on: June 17, 2016, 07:50:24 PM »
I'll keep my fingers crossed.  This person converted everything to one switch, so lights, horn, signals and starter are all on the same switch.  I'm not familiar with the original set up.  I might as well figure this out while I'm at it.  Any suggestions for replacement?
Now
'73 Eldorado
'77 T3
Then
'66 Honda Dream
'74 Honda CB750

Offline rodekyll

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Re: T3 Wiring
« Reply #12 on: June 17, 2016, 08:04:24 PM »
The suggestion has been made by several -- Greg Bender's harness.  Read up ^

Online nick949

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Re: T3 Wiring
« Reply #13 on: June 17, 2016, 08:30:13 PM »
Another recommendation for Greg's harness. I published an article in RealClassic Magazine No. 144 (April 2016) about rewiring my Eldorado from top to bottom, but the long and short of it was: everything Greg supplies is quality, perfectly labelled and his instructions are a model of clarity.

Even a electrical stumblebum like me managed to do it with no issues and everything now works - perfectly.  It's worth every penny.

Nick

Offline ctk111

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Re: T3 Wiring
« Reply #14 on: June 17, 2016, 08:33:40 PM »
I did and I'm planning on purchasing it.  I was referring to purchasing a new starter and light switch for on the handlebars.  Thanks again for all the help.
Now
'73 Eldorado
'77 T3
Then
'66 Honda Dream
'74 Honda CB750

Offline rodekyll

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Re: T3 Wiring
« Reply #15 on: June 17, 2016, 08:45:59 PM »
I did and I'm planning on purchasing it.  I was referring to purchasing a new starter and light switch for on the handlebars.  Thanks again for all the help.

Sorry -- I misunderstood.  I get my switchgear from Honda as a rule, so I don't know what oem-compatible sources are out there.  A lot of what you can use depends on how you feel about 'correctness'.  The more correct it needs to be the fewer the choices.

Starters.  Don't get me started.    :whip2:  That euromotolectric (or however they spell it) sells the Bosch unit and has the valeo on sale for ~$125.  Some folks have had good luck with valeo.  I so far have not.  Valeo should be the better technology.  I'm disappointed.  Bosch seems to chug on forever, but it's a heavy doggie and sucks power like a BIG heavy doggie.  The Bosch in my '76 Convert went for about 30 years.  The first Valeo lasted about 4, and the second about one.

You mentioned also doing turn signals.  Look into LED before you make any decisions about tail and marker lights.  It's a technology that's finally coming in to it's own.

Moto

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Re: T3 Wiring
« Reply #16 on: June 17, 2016, 09:54:23 PM »
Check with MGCycle.com for replacement switches and, possibly, starter rebuilds, which they used to offer. That's where I got my left- and right-side switches, and some good advice about which ones to buy. I see now that the models I got fifteen years ago are no longer available, so I can't suggest them.

Another really good source is Harper's Moto Guzzi, harpermoto.com. They have many OEM parts as well as aftermarket ones.

You could ask Greg Bender for his recommendations on switches when you buy a wiring harness. He can customize harnesses, so make sure you know what switches are going to be used before finalizing your harness order, and make sure to talk it through with Greg.

I do all my own wiring and haven't had any problems, but it requires some skill and tools. If I didn't have those I'd be contacting Greg for sure.

Moto

Offline Testarossa

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Re: T3 Wiring
« Reply #17 on: June 17, 2016, 11:53:31 PM »
A lot of us have had good luck with K&S switchgear, and Bender makes pigtail adapters so that some of the K&S units are plug-and-play to the Molex connex on Guzzi wiring harnesses. It might not be a bad idea to buy new switches along with the harness, and you should look into relays for the headlamp so the full 60 watts doesn't have to go through a switch contact.
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Offline ctk111

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Re: T3 Wiring
« Reply #18 on: June 18, 2016, 09:55:33 AM »
Yeah, makes sense to talk with Greg Bender first.  I'll send him an email and see what he suggests.  It looks like a mess when I pull off the headlight, so might as well clean up as much as I can now.
Now
'73 Eldorado
'77 T3
Then
'66 Honda Dream
'74 Honda CB750

Offline charlie b

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Re: T3 Wiring
« Reply #19 on: June 18, 2016, 10:27:19 AM »
Yep, as long as you are replacing the harnes you might as well do all the rest while you are there.

I redid my wiring when I replaced the alternator.  Already had LED's on everything but also replaced the relays and the turn signal blinker unit (solid state version).  The nice thing is it looks much nicer and it is so much easier to see where a problem is.  Since I was building my own I also removed a lot of wiring I didn't need as well as redoing the starter relay wiring.  Probably lost a pound or two  :)
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Offline Kiwi_Roy

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Re: T3 Wiring
« Reply #20 on: June 18, 2016, 10:48:19 AM »
I've heard nothing but good about Greg's harnesses and they are much cheaper than trying to do one on your own, it sounds like you may need some new switches though

One thing  would like to add to any old bike is a main fuse in the wire from the battery to ignition switch, something like a 30 or 40 Amp just in case of worst case and
an easy way to isolate all the small wiring.
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Offline Testarossa

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Re: T3 Wiring
« Reply #21 on: June 18, 2016, 03:13:47 PM »
Quote
Since I was building my own I also removed a lot of wiring I didn't need as well as redoing the starter relay wiring.
:thumb:

Amen to this. The harness has a few unnecessary runs -- the sidestand circuit for instance, if so equipped. And to avoid startus interuuptus it's smart to do shorter, more direct runs for the everything that leads to the starter relay and solenoid. No reason that amperage needs to feed through tiny molex contacts.
70 Triumph TR6R, 74 850T, 74 Yamaha TA125, 89 Mille GT, 99 F650, 2013 Yamaha XT250; 1974 MGB
Gone: 59 Piper Comanche 250, 69 Harley/Aermacchi 350SS, 71 Honda CB500/4, 74 Laverda 750 SF2, 91 Suzuki VX800, 50cc two-stroke scoot, 83 XR350R

 


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