Parallel glow plugs

I have a Series 3 1980 diesel, want to change to a parallel set-up and should be grateful for any advice you can give.
A diagram is included to help me and hopefully you.
I intend leaving the ballast resistor and bracket in place so I just connect the wire to the plugs to the terminal 1 (present 22 v input thick red brown).
Do I then replace the 6v bulb and run a wire from that to earth or to 2 the other end of the resistor as it is now?
It seems to me that the effect will be the same but am not very clued up and would welcome advice.
Do I buy a kit, if so any recommendations, or just buy the plugs and make up my own wiring which is what I have always done.
Thanks very much.
Faber

I have just realised that the new plugs do not need to go to a separate earth.

Faber

I used a relay on mine but the original wires are heavy enough
You do need a 12v little bulb as you’re passing 12v through not 6 anymore

Think of the bulb simply with 2 leads one end 12v positive when the key turned to heater plug and other end to earth
Yes just stick to one end of ballast resistor
It is easy to buy kit but if you’re handy with doing the ends ok
And as you realised DONT a fit the end plug cable to earth as original or it will melt the cables

Very useful. Thanks
Faber

When I did this I had an idea of running a wire back from the top of the number 1 cylinder plug (front of engine) to power the bulb.

That way you would know if there was a break in the circuit somewhere as the bulb wouldn't light up. I never got round to actually doing it.

Thanks. All this is very interesting. I have had numerous issues with glow plugs and their wires shorting behind the fascia, leading to replacing wiring, and not bothering with the warning light. I sometimes think the beast has a will of its own...you solve one problem and another pops up!

Faber

Webley1991 said:

When I did this I had an idea of running a wire back from the top of the number 1 cylinder plug (front of engine) to power the bulb.

That way you would know if there was a break in the circuit somewhere as the bulb wouldn't light up. I never got round to actually doing it.

Click to expand...

Using number 4 plug still powers the bulb at 12v when the glow plugs on but just need a shorter wire

Faber said:

Thanks. All this is very interesting. I have had numerous issues with glow plugs and their wires shorting behind the fascia, leading to replacing wiring, and not bothering with the warning light. I sometimes think the beast has a will of its own...you solve one problem and another pops up!

Faber

Click to expand...

I recall that ballast resistor should not be earthed through the connections otherwise that would cause a short , apart from that the glow plug power from ignition switch should be fairly straightforward

One of the kits comes with a diagram. Sadly I can’t remember which one. I’m not even sure the choice is there anymore. Britpart seem to have cornered the market.

Bobsticle said:

One of the kits comes with a diagram. Sadly I can’t remember which one. I’m not even sure the choice is there anymore. Britpart seem to have cornered the market.

Click to expand...

Thanks. If that is the case I shall probably buy the plugs separately and make up the wiring.
Faber

steve2286w said:

Using number 4 plug still powers the bulb at 12v when the glow plugs on but just need a shorter wire

Click to expand...

That wouldn't show a break in the wiring between plugs 4 and 1. That was the purpose of the idea of using a wire back from plug 1.

Understood and thanks

Faber

Webley1991 said:

That wouldn't show a break in the wiring between plugs 4 and 1. That was the purpose of the idea of using a wire back from plug 1.

Click to expand...

I see the logic , but that wouldn’t show a glow plug not working and for a break in the heavy cable that would be evident by visual inspection

Ed