Install GFS pickups in Yamaha Pacifica 302S

[bohma2000]

Hi all,

I’m not an electrician and have never done anything like this before. I am trying to replace the stock pickups in a Yamaha Pacifica 302S (Tele copy) with GFS pickups.

Neck - Alnico Fatbody neck pickup (I37)
Bridge - Alnico Boutique Bridge Pickup (I29)

Both of these GFS pickups have got just two separate wires coming from them.

When I unscrewed the bridge plate and pickup cavity plate and examined the pickups installed by Yamaha I found that they had an extra strand of multicore wire along with the two wires from both pickups. All of these wires are made into one cable.

Current wiring
Neck pickup.
Red wire goes to the 3 way switch.
White wire and multicore wire are soldered together in the control cavity and a wire goes from these and is soldered to the back of the volume pot.

Bridge pickup
Red wire goes to the 3 way switch
White wire is soldered to the back of the volume pot.
Multicore wire is soldered to a different part of the volume pot.

What is the purpose of the multicore wire? Is this for shielding or grounding?

I have downloaded a standard Telecaster wiring diagram from the Seymour Duncan website and this shows a ground wire from the bridge soldered to the volume pot? I don’t appear to have this on my guitar! There is no place on the back of the bridge plate to solder a ground wire. If I completely rewire the guitar using the Seymour Duncan diagram how will it be grounded?

Help anybody?

Bren

[spud1950]

Let's see if I can break this down for you.First thing, the neck pickups.The Yamaha has a metal cover,the GFS doesn't.The reason the Yamaha has an extra wire is that it is connected to the cover to ground it,which is why it solder to the pot body which is a ground source.The white lead wire is the coil ground wire,also connected to ground via the pot body. Since the GFS has no cover,it doesn't need the extra ground wire.
On to the bridge pickups.They have metal baseplate's which need to be connected to ground.It seems the Yamaha does this by having an extra wire soldered to baseplate and connected to the pot body as a ground source. The GFS pickup does it differently.The baseplate is just connected to coil lead ground wire itself with a little jump wire, no long wire needed. Either way, the baseplate is getting connected to ground.
As to the bridge ground wire.The bridge must be connected to a ground source.Sometimes a wire is run,as in the diagram,from the bridge to a pot body.By the way,this wire is not soldered to the bridge.You strip the insulation off the end of the wire and sandwich the bare end between the bridge and the body. The other way the bridge gets grounded is that since the pickup baseplate is connected to ground, the ground connection gets transfered to the bridge because the three pickup height adjustment screws are in contact with both the baseplate and the bridge, resulting in a continuous ground connection,which is why Yamaha doesn't have a seperate bridge ground wire.
Now,to the wiring.Traditionally,the black lead is ground and the white is hot.I checked the GFS site so the neck pickup,having the same color leads as in the diagram,gets wired that same way.The picture of the GFS bridge pickup,however,shows a black lead and a red lead.You must determine which is which.The ground lead wire will be the one that is connected to the metal baseplate and will correspond the black wire in the diagram.It may very well be the black lead on the GFS pickup,but double check just to make sure.This is important,you don't want them hooked up in reverse.

[bohma2000]

Thanks for the advice Spud1950.

I tried to follow your instructions and the Standard Telecaster wiring diagram from Seymour Duncan. However when I plug the guitar into an amp, all I can hear is a humming sound. I’ve tapped the pickups with a screwdriver and raised and lowered the volume but this does not produce any sound through the amp.

I wired up as follows:-

Neck Pickup – White wire to 3 way switch, black wire to back of volume pot.

Bridge Pickup – Red wire to 3 way switch, black wire to back of volume pot.

According to GFS, the black wire on both pickups is the ground.

I had to run a new ground wire from under the bridge plate which I soldered to the back of the volume pot. At the other end of this I just bared about half an inch of wire and taped it to the underside of the bridge plate.

There was a black wire soldered to the back of the tone pot in the original wiring. I can’t remember where this originally went but I soldered it to the back of the volume pot as this seems to be following the instructions in the diagram from Seymour Duncan.

The cable from the jack socket has a wire sheathed in white plastic and a multi-core wire which is not sheathed. Both of these are enclosed in a red sheath. The white wire is soldered to the middle lug of the volume pot and the multi-core, unsheathed wire is soldered to the back of the tone pot in the same place as one of the legs of the capacitor.

Apart from the above, I left the wiring as it came from Yamaha. I am attaching a few photos of my attempts at wiring. Please don’t laugh at the amateurish soldering effort!

If you can see any glaring errors I would really appreciate it if you could point them out.

Cheers,

Bren.

[spud1950]

The humming and no sound indicates to me that there's a hot and ground wire reversed somewhere. I have a suspicion that the bridge pickup is wired wrong. I know for a fact that people have had problems wiring some GFS pickups because despite what they state in their wiring instructions,the hot and ground lead wires on some models are sometimes the opposite colors of what they're stated to be. You can try reversing the positions of the bridge pickup wires.Solder the red to the pot and black to the switch and see if that doesn't fix it. Like I said before,it would be good to look at the back of the pickup and see which lead is connected to the metal baseplate,as that will determine for sure which is the ground wire,despite what color it is.

[bohma2000]

I've taken off the bridge plate and examined the bridge pickup. The black wire has a thin wire soldered to the brass base plate of the pickup. I asssume therefore that the black wire in this case *is* the ground.

[DAY211@CHARTER.NET]

Hi all,

I’m not an electrician and have never done anything like this before. I am trying to replace the stock pickups in a Yamaha Pacifica 302S (Tele copy) with GFS pickups.

Neck - Alnico Fatbody neck pickup (I37)
Bridge - Alnico Boutique Bridge Pickup (I29)

Both of these GFS pickups have got just two separate wires coming from them.

When I unscrewed the bridge plate and pickup cavity plate and examined the pickups installed by Yamaha I found that they had an extra strand of multicore wire along with the two wires from both pickups. All of these wires are made into one cable.

Current wiring
Neck pickup.
Red wire goes to the 3 way switch.
White wire and multicore wire are soldered together in the control cavity and a wire goes from these and is soldered to the back of the volume pot.

Bridge pickup
Red wire goes to the 3 way switch
White wire is soldered to the back of the volume pot.
Multicore wire is soldered to a different part of the volume pot.

What is the purpose of the multicore wire? Is this for shielding or grounding?

I have downloaded a standard Telecaster wiring diagram from the Seymour Duncan website and this shows a ground wire from the bridge soldered to the volume pot? I don’t appear to have this on my guitar! There is no place on the back of the bridge plate to solder a ground wire. If I completely rewire the guitar using the Seymour Duncan diagram how will it be grounded?

Help anybody?

Bren