Glow plug conversion

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dag019

dag019

Well-Known Member
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Location
Warwick
I am planning on fitting new glow plugs today to my. I have bought the kit for the new style glow plug and wiring, to replace my existing pig tails. I know that the new style earth through the block and need to be moved to the input side of the ballast resistor so they get a full 12v.
My question is on how to wire up the glow plug warning light as there have been contradictions in the information I have read.
I have also read about people saying this will quickly destroy the ignition switch and a relay is needed. is this true or is this scare mongering, as my 110 functioned fine before its bulkhead conversion (complete 300tdi) and I believe that went straight through the switch.
 
I put a relay on mine I never checked how much load either system uses
the ballast resistor becomes redundant
So this is bypassed by just using one post for the connector then going to injector 4
In effect the glow light is a bulb with two wires coming off it when it’s disconnected from ballast resistor
The warning light with the small wires needs 12v when key Turned to glow plug position so one end Must be connected to 12v heavy cable and other end to earth

if you use same principle but using relay for heavy loads that makes it better for ignition switch


9BB75FB4-A696-4A75-8D13-AB685B556D8D.png
 
As per what Steve says, but pigtail warning bul is Iirc 6v, so needs swapping to 12 volt.
Have read new style not as effective as pig tails, how true I have no idea?

Best mod for n/a diesel n/a is tdi starter motor.

Why I wrote n/a twice I have no idea!
 
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Some modern glow plugs are self regulating and current reduces as they get hotter 200tdi ones are in the class my 4 in 200di take 38A initially which then drops off quite quickly as they get up to temperature.
Something to do with them beeing double wound, been an electrician all my working life red up on them but went over my head , ammeter reading showed it to be true though.
 
lynall said:
As per what Steve says, but pigtail warning bul is Iirc 6v, so needs swapping to 12 volt.
Have read new style not as effective as pig tails, how true I have no idea?

Best mod for n/a diesel n/a is tdi starter motor.

Why I wrote n/a twice I have no idea!
Click to expand...
If I take the glow plug light feed from the other side of the ballast resistor (not planning on removing it) does that mean it would still have a 6v feed and I would not need to change the bulb? Then for the warning light I just make sure the other end is earthed.


Also does a tdi starter motor fit a 2.25? If so is it a straight swap or does anything else need modifying? The reason for changing the glow plugs is a sluggish start, but it does spin over relativly slowly even with a new battery. But I know these are harder to start that either the tdi in the 110 or the diesel in the fordson I have.
 
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The feed comes from the heavy wires not the ballast resistor but you can connect to the ballast resistor post
You won’t have a 6v supply so bulb needs changing (as this only happens with voltage drop across the resistor
Not sure if you can see what I’ve done On pic as filter in way on my 200 Di
But wired the same as on the 2286
One end of heater plug light is earthed on ballast resistor holding down screw not as shown on sketch
200 tdi starter fits 2286 series straight swap on mine other one was getting noisy
FFF7DA20-04E6-4CB9-878D-188BA94673D7.jpeg
3797AEB1-60B9-4F5D-BE74-AA12C78B4721.jpeg
 
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steve2286w said:
The feed comes from the heavy wires not the ballast resistor but you can connect to the ballast resistor post
You won’t have a 6v supply so bulb needs changing (as this only happens with voltage drop across the resistor
Not sure if you can see what I’ve done On pic as filter in way on my 200 Di
But wired the same as on the 2286
One end of heater plug light is earthed on ballast resistor holding down screw not as shown on sketch
200 tdi starter fits 2286 series straight swap on mine other one was getting noisyView attachment 211237View attachment 211238
Click to expand...
apologies that was my typo, now edited to correct. Not looking at a relay at present so leaving the circuit going through the switch. My understanding of the current system is: battery to switch, switch to ballast resistor, ballast resitor to first glowplug and warning light, glow plugs in series, last glow plug earthed. Could I with the existing set up take the 12v feed to the new parallel plugs from the "input" side of the ballast resistor, and the 6v feed to the warning light from the "output" side of the resistor?
 
Your new style glow plugs are wired in parrellel as I presume not in series as the old pig tail,plugs
Each of These earth Through the block , if you connnect the earth at no 1 as in old series set up you will melt your cables
dag019 said:
Could I with the existing set up take the 12v feed to the new parallel plugs from the "input" side of the ballast resistor, and the 6v feed to the warning light from the "output" side of the resistor?
Click to expand...
I don’t think that would work as I think the heater plug load not going through ballast resistor would not drop the volts
I’m not 100% on that but you could try the most would happen poss it would blow the bulb
Before I put the 200di in my light did not glow but you know when turning key when Plug heat is on
 
dag019 said:
If I take the glow plug light feed from the other side of the ballast resistor (not planning on removing it) does that mean it would still have a 6v feed and I would not need to change the bulb? Then for the warning light I just make sure the other end is earthed.


Also does a tdi starter motor fit a 2.25? If so is it a straight swap or does anything else need modifying? The reason for changing the glow plugs is a sluggish start, but it does spin over relativly slowly even with a new battery. But I know these are harder to start that either the tdi in the 110 or the diesel in the fordson I have.
Click to expand...


I had tdi starter on the old 2 litre derv, am led to beieve it pretty much fits all the derv blocks, massive difference to starting ability, even in depths of winter it threw the engine over at a rate of knotts.
When I converted to tdi I basically used one stud of the reisistor to connect all the wires and glow plugs to, pretty sure mine feed straight from the tractor ign switch.
 
Didn’t I read somewhere that glow plugs only use a couple of volts but the amps are high?
Not sure why that sprung to mind. Might be my age :oops:
 
steve2286w said:
Your new style glow plugs are wired in parrellel as I presume not in series as the old pig tail,plugs
Each of These earth Through the block , if you connnect the earth at no 1 as in old series set up you will melt your cables

I don’t think that would work as I think the heater plug load not going through ballast resistor would not drop the volts
I’m not 100% on that but you could try the most would happen poss it would blow the bulb
Before I put the 200di in my light did not glow but you know when turning key when Plug heat is on
Click to expand...

Looking at the wiring diagrams the warning bulb is in parallel with the ballast resistor so it may be easier to just lave the "input" feed so that the bulb gets a full 12v change it over toa 12v bulb and then swap the other end form the "output" side of ballast resistor to an earth point. Does anyone know what bulb I need to convert it to 12v, is it the same as the dial illumination bulbs?
 
lynall said:
I had tdi starter on the old 2 litre derv, am led to beieve it pretty much fits all the derv blocks, massive difference to starting ability, even in depths of winter it threw the engine over at a rate of knotts.
When I converted to tdi I basically used one stud of the reisistor to connect all the wires and glow plugs to, pretty sure mine feed straight from the tractor ign switch.
Click to expand...
Many thanks I will look into that. Quick question, am I correct in assuming if all diesel blocks are the same there is no difference between a 2/300tdi starter? Looking s/h there seem to be a few of each about.
 
dag019 said:
Many thanks I will look into that. Quick question, am I correct in assuming if all diesel blocks are the same there is no difference between a 2/300tdi starter? Looking s/h there seem to be a few of each about.
Click to expand...
if you have a tdi n a series wire glow plugs through the tdi glowp plug relay ,using switch glow plug terminal as trigger and it has an indicator take of for a light
starters fit all the 4 diesels, except they use the smaller gear reduction motors for those with turbos as the earlier large starter wouldnt fit,but smaller reduction motor would fit on a non turbo
 
jamesmartin said:
if you have a tdi n a series wire glow plugs through the tdi glowp plug relay ,using switch glow plug terminal as trigger and it has an indicator take of for a light
starters fit all the 4 diesels, except they use the smaller gear reduction motors for those with turbos as the earlier large starter wouldnt fit,but smaller reduction motor would fit on a non turbo
Click to expand...
Many thanks for the reply, I have a 5mb 2.25 diesel in my series, which is currently very sluggish to start. I have done the obvious and cleaned up all of the wiring connections and replaced the earth cables. My next port of call was the glow plugs. I have one of the kits (glowplug and wiring) to upgrade from the series pigtails to parallel modern glow plugs. I am working with the original wiring loom which does not have a relay and is fed direct from the switch.

If the glow plugs do not solve the issue the starter was next on the list, it is good to know that the starter fit all engines and I will upgrade to a tdi starter motor if it comes to that.
 
dag019 said:
Looking at the wiring diagrams the warning bulb is in parallel with the ballast resistor so it may be easier to just lave the "input" feed so that the bulb gets a full 12v change it over toa 12v bulb and then swap the other end form the "output" side of ballast resistor to an earth point. Does anyone know what bulb I need to convert it to 12v, is it the same as the dial illumination bulbs?
Click to expand...
Agree that what I was saying above
6v warning bulb is Lucas 982
12 v warning light bulb is Lucas 987
You get reasonable access removing the 2 big screws on instrument panel
 
I had the 5mb diesel and the tdi engine Didnt come with glow plugs relay
The pig tails from manual are 1-7 volts and 38 to 42 amps
The voltage drops in each plug from no 4
I would expect the overall Power for both systems must be similar To get reqd heat in whether 12v or above 1-7
Easy to wire relay

200tdi starter on left containing the low gearing bit James mentioned
478F0C4F-B253-4AFE-9FA8-0E803BA7CB6B.jpeg
 
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dag019 said:
My next port of call was the glow plugs. I have one of the kits (glowplug and wiring) to upgrade from the series pigtails to parallel modern glow plugs. I am working with the original wiring loom which does not have a relay and is fed direct from the switch.
Click to expand...
There is a procedure to test the pig tail original ones in manual too could be an easy first step
 
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