Glow plug relay question

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Nerocuba

Active Member
Posts
94
Location
Hertfordshire
Another silly question, so bare with me.
It's a 1988 110 with 300tdi up front but have no idea if that is the original engine. There is no little "coil" light on the dash, so I have no idea if the glow plugs are heating up or not. I can't hear any clicking or ticking from any relays when the ignition gets turned on. It doesn't start immediately but it doesn't struggle too much. Quite a bit of white/blue smoke at certain revs at first but clears up quite quickly after the initial start. So, I thought maybe I'll get new glow plugs and see if that helps but now wonder if the relay may be faulty.... Difficult to know because of the lack of dashboard light. There is a choke light but that doesn't come when the key is turned either....
Also, if people think it may be the relay, does anyone know which one it is, if its on the main board inside the vehicle?
Thanks in advance.
 
300 isn't original but the Landy it came out of would have had a relay.
When you turn ign switch to the position that the dash warning lights are on- is there a sprung resistance to the key before you turn it further to engage the starter? This resistance between dash lights and starter engagement is where the glowplugs would be energised originally, you have to hold the key in that position for a few seconds before engaging the starter. In that position the choke light should be illuminated. If you don't have that sprung resistance on your ign switch your Landy may have been petrol before the 300 was fitted.
There are a few options available to get them working,
Off the switch as above.
Fit a timer relay.
Manual non latching push button switch.
 
300 isn't original but the Landy it came out of would have had a relay.
When you turn ign switch to the position that the dash warning lights are on- is there a sprung resistance to the key before you turn it further to engage the starter? This resistance between dash lights and starter engagement is where the glowplugs would be energised originally, you have to hold the key in that position for a few seconds before engaging the starter. In that position the choke light should be illuminated. If you don't have that sprung resistance on your ign switch your Landy may have been petrol before the 300 was fitted.
There are a few options available to get them working,
Off the switch as above.
Fit a timer relay.
Manual non latching push button switch.
 
Follow the cable that links all 4 glow plugs to the back of the engine and see where they go?
 
300 isn't original but the Landy it came out of would have had a relay.
When you turn ign switch to the position that the dash warning lights are on- is there a sprung resistance to the key before you turn it further to engage the starter? This resistance between dash lights and starter engagement is where the glowplugs would be energised originally, you have to hold the key in that position for a few seconds before engaging the starter. In that position the choke light should be illuminated. If you don't have that sprung resistance on your ign switch your Landy may have been petrol before the 300 was fitted.
There are a few options available to get them working,
Off the switch as above.
Fit a timer relay.
Manual non latching push button switch.
Lol
Thanks Flossi, I am. Not sure now but will be sure to check that out.... I want to say no, there isn't that sprung resistance but can't be sure before checking. I will follow the leads when I get the new plugs and change them on the weekend Lynall. Where should they go? I'm sure the choke light doesn't come on at all..... Does this mean my plugs aren't heating up at all? If it hasn't got what you described?
 
Originally the cable from number 4 glowplug would go direct to one of the larger terminals on the ign switch. The other large terminal on the ign switch is battery feed, all the sprung resistance position does is join those 2 large terminals together sending full battery power to the glowplugs.
 
Originally the cable from number 4 glowplug would go direct to one of the larger terminals on the ign switch. The other large terminal on the ign switch is battery feed, all the sprung resistance position does is join those 2 large terminals together sending full battery power to the glowplugs.
I see.... I'm assuming I will need a manual switch fitted then.... Never ending, this Defender ownership hey hahaha
 
I see.... I'm assuming I will need a manual switch fitted then.... Never ending, this Defender ownership hey hahaha
You haven't said what type ign switch you have yet.
If it is a petrol one you can buy the diesel one and wire that up or fit a small tidy manual one and run it via a relay which I did on an old series I had 20 odd years ago (petrol to diesel conversion).
Tell us what switch you have and we can go from there.
 
You haven't said what type ign switch you have yet.
If it is a petrol one you can buy the diesel one and wire that up or fit a small tidy manual one and run it via a relay which I did on an old series I had 20 odd years ago (petrol to diesel conversion).
Tell us what switch you have and we can go from there.
OK thanks, I will tell you when I make 100% sure, so will check the weekend.
Thanks again
 
I have a 300tdi fitted to a 1985 (used to be v8).

I have a manual setup for glow plugs. A relay behind the speaker box and it's wired to miss the ignition completely. A small switch which i stuck into the dash turns the relay on, it's connected to instrument light 'BREAK' that was not being used. (the switch has a small light in it that turns on when used). I have to switch it on and wait for the BREAK light to go out and then I switch it off and start the engine. Summer I don't bother.
 
I have a 300tdi fitted to a 1985 (used to be v8).

I have a manual setup for glow plugs. A relay behind the speaker box and it's wired to miss the ignition completely. A small switch which i stuck into the dash turns the relay on, it's connected to instrument light 'BREAK' that was not being used. (the switch has a small light in it that turns on when used). I have to switch it on and wait for the BREAK light to go out and then I switch it off and start the engine. Summer I don't bother.
That sounds like a very clever idea but unfortunately I wouldn't have a clue how do that without running the risk of burning my Landy to the ground lol. I'm sure I'll find someone who would be able to do one for me. Thanks again for all the help and ideas.
 
That sounds like a very clever idea but unfortunately I wouldn't have a clue how do that without running the risk of burning my Landy to the ground lol. I'm sure I'll find someone who would be able to do one for me. Thanks again for all the help and ideas.

A relay is very nice, but you can get heavy duty switches so it is basically one wire to switch and wire from switch to glow plugs.

This kind of thing, simple to fit and wire up, https://www.ebay.co.uk/itm/Heavy-Du...145720&hash=item4b6b234109:g:ABYAAOSwukRdgj~i
 
That sounds like a very clever idea but unfortunately I wouldn't have a clue how do that without running the risk of burning my Landy to the ground lol. I'm sure I'll find someone who would be able to do one for me. Thanks again for all the help and ideas.

I would encourage you to have a go. It would be a good project. You will need the skills the next time the landy goes wrong.

Easiest way would be to put a glow plug relay in the engine bay. Take a thick wire from the starter motor (or alternator) to it (add a fuse into the system), and then from the relay to the glow plus which should be wired in series.

Then you will need to put an earth from the relay to something metal.

Then a wire from anything live (battery, instruments) to a switch in the dash which lights up when on. After the switch it should go to the relay.
 
I would encourage you to have a go. It would be a good project. You will need the skills the next time the landy goes wrong.

Easiest way would be to put a glow plug relay in the engine bay. Take a thick wire from the starter motor (or alternator) to it (add a fuse into the system), and then from the relay to the glow plus which should be wired in series.

Then you will need to put an earth from the relay to something metal.

Then a wire from anything live (battery, instruments) to a switch in the dash which lights up when on. After the switch it should go to the relay.
Cheers Nial, I do agree that having a go is the best option and I am up for most things, I am going to attempt my steering UJs this weekend but I do worry about messing with electrics, as I absolutely no idea about that sort of thing at all.... The last thing I want is something catastrophic to occur and my insurance company to be rolling around on the floor laughing, as they tear up my claim cheque.... And we all know they would quite happily do that. Lol
 
assuming original engine
Defender_Electrical_Library-028.png
 
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