Partial Wilson switch/total glow mess 24v BJ40 with 3B (1 Viewer)

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Joined
Mar 3, 2021
Threads
3
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Location
Czech Republic
Hi All,

Sorry if the glow stuff/Wilson switch has been bashed to death on this forum but unfortunately I am kind of in a state from one of the previous owners where I have neither a super glow system or proper Wilson switch.

My BJ40 is 24v and it was upgraded to a 3B engine at some point in its life, the wiring seems a bit of a mishmash (could be from another Land Cruiser model?). Anyway it was starting like a dog when it was cold so I decided to investigate.

Unfortunately my electrical knowledge is very basic, I made a diagram below how I think my current glow system works. It looks very simple and incorrect from what I understand and also doesn't work properly.

My initial troubleshooting consisted of checking the voltage on the current glow plugs which was showing at around 9v which I thought was strange considering the 24v setup. When removing the old glow plugs I discovered they were 10.5v so I got excited and thought I was onto a winner "someone put the wrong plugs in" I said. I purchased Denso 20.5v ones as per the Toyota number 19850-68040 but after excitedly putting them in I was disappointed when I went to start it and it spluttered into life like the old dog it was before the glow plug change, seeming not to have improved at all.

After this disappointment I decided to investigate more and try and find something online about what's going on. I did some more tests and discovered that I maybe had something in the past called super glow but someone looks to have hacked away. I discovered that they also left some part of the bars there and the 24v line going to these bars seems to drop to 13v at the first twist like some kind of resistor. I thought this seems stupid, my 20.5v glow plugs are only getting 13v meaning they probably don't work well.

The last troubleshooting I did was to put a direct jump lead from the positive on my battery to the first glow plug on the bar. I could then see the glow plugs were getting 24v. After around 15 seconds I took the lead off and fired it up. To my excitement it started perfectly and instantly.

Now to how it is currently setup as per one of the previous owners

Video of the wiring/glow setup:



Video of start with direct 24v to glow plugs avoiding blow button, dodgy wiring etc:



Glow wiring as it currently stands from the previous owners (how I believe it is unless I am missing something):
1614861905950.png


So I believe I need to fix all this, would it be possible for someone to advise/guide me on this. As I said, I am not very advanced with electrics so I am kind of clueless as to what gauge wire I need to put in there, what relay to get plus I would like to make the old glow coil on the dash work so I can see how the glow plugs are glowing if this is possible and get a nicer button that suits the BJ40.

Thanks for all your help and time in advance, I really appreciate it.

Stuart.
 
A relay is usually used in conjunction with a momentary switch. The relay can handle the current going to the glow plugs. A small momentary switch on your dash usually won't be rated for carrying the current those plugs will draw initially. (The plug's resistance increases quickly as they heat up so less current is flowing when they get hot.)

The resistor bar on the intake manifold is used with the Super Glow system. Super Glow is a two-stage setup where the plugs get full battery voltage for a brief period before current is switched through the resistor just to provide enough voltage to keep the plugs warm for an extended period without burning them out. I think the 24v Super Glow system used 14.5v plugs, but I don't know that for sure. (I've never had a 24v Cruiser.) 20.5v plugs make sense for a switch-controlled glow system that gets full battery power, just be sure you're wiring up straight to the bus bar and not through the resistor.

Lots of people use Ford starter relays for supplying the glow plugs. They are cheap and easy to wire up.
 
Hi All,

So I believe I need to fix all this, would it be possible for someone to advise/guide me on this. As I said, I am not very advanced with electrics so I am kind of clueless as to what gauge wire I need to put in there, what relay to get plus I would like to make the old glow coil on the dash work so I can see how the glow plugs are glowing if this is possible and get a nicer button that suits the BJ40.

Thanks for all your help and time in advance, I really appreciate it.

Nice work so far.. you've learnt a lot in a short time :) I would rip out everything but the glow plug rail and put in a fresh Wilson switch setup with a decent relay driven by a momentary push button. I would NOT try and get the old dash glow coil indicator working, it'll just be a future failure point. I tend to assess my glow plug health (and) battery health by watching the digital Voltage Gauge on my dash during the glow operation - I know what voltage drop across the system I generally see and if the glow system isnt working as it normally does its pretty obvious from the voltage gauge. The 20.5V plugs you've bought are perfect for a simple Wilson setup so no loss there.
 
A relay is usually used in conjunction with a momentary switch. The relay can handle the current going to the glow plugs. A small momentary switch on your dash usually won't be rated for carrying the current those plugs will draw initially. (The plug's resistance increases quickly as they heat up so less current is flowing when they get hot.)

The resistor bar on the intake manifold is used with the Super Glow system. Super Glow is a two-stage setup where the plugs get full battery voltage for a brief period before current is switched through the resistor just to provide enough voltage to keep the plugs warm for an extended period without burning them out. I think the 24v Super Glow system used 14.5v plugs, but I don't know that for sure. (I've never had a 24v Cruiser.) 20.5v plugs make sense for a switch-controlled glow system that gets full battery power, just be sure you're wiring up straight to the bus bar and not through the resistor.

Lots of people use Ford starter relays for supplying the glow plugs. They are cheap and easy to wire up.
Thanks for the detailed reply. So I just need to figure out what relay to buy, what gauge wire and how to wire it up with a button and light. I will get rid of the resistor bar that's still there and I should be good I suppose.

Thanks very much.
 
Nice work so far.. you've learnt a lot in a short time :) I would rip out everything but the glow plug rail and put in a fresh Wilson switch setup with a decent relay driven by a momentary push button. I would NOT try and get the old dash glow coil indicator working, it'll just be a future failure point. I tend to assess my glow plug health (and) battery health by watching the digital Voltage Gauge on my dash during the glow operation - I know what voltage drop across the system I generally see and if the glow system isnt working as it normally does its pretty obvious from the voltage gauge. The 20.5V plugs you've bought are perfect for a simple Wilson setup so no loss there.
Thanks, yeah I quite enjoy troubleshooting and it can be very rewarding if everything works out. So you added some digital voltage monitor which is connected to your battery? How would you know if there is something wrong with a glow plug? Less drop on the voltage when you glow because one is not working? You wouldn't happen to know what relay I should get? Apparently a Ford one is good but I feel bad to put something from Ford in a Japanese car 🤣plus I am not sure if the Ford one is 24v

Thanks
 
@FatalErrorStu , If you have doubt about your glow plugs, there are lots of videos on YouTube showing how to test them with your battery. You have to pull them out, to test them as such. I have a digital volt meter, and get about a half a volt drop when I manually glow. It would be hard to analyze things / a bad glow plug Via the volt meter on your dash. I recommend replacing all of them at once if they are old, or pull them out to test, don‘t rely on a volt meter for that. However, you can check the ohms / resistance of your removed glow plugs with a multi meter. Hope that helps.
 
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The Ford-style relay is more of a generic thing these days. I think Ford was the first company to use them in large quantities but I've seen them in lots of different vehicles and heavy equipment (tractors, excavators, loaders, etc.)

There are some nice 24v Dodge/Cummins relays available for the glow screens they used on the 5.9L in the early 2000s. I have a couple somewhere in my garage that I could dig up and snap a photo for you. The 24v relays tend to be a little smaller than the 12v because they usually don't need to carry as much current.
 
@FatalErrorStu , If you have doubt about your glow plugs, there are lots of videos on YouTube showing how to test them with you battery. You have to pull them out, to test them as such. I have a digital volt meter, and get about a half a volt drop when I manually glow. It would be hard to analyze things / a bad glow plug Via the volt meter on your dash. I recommend replacing all of them at once if they are old, or pull them out to test, don‘t rely on a volt meter for that. However, you can check the ohms / resistance of your removed glow plugs with a multi meter. Hope that helps.
Thanks for your reply. I think my glow plugs are fine, they are brand new and seem to be working fine with a 24v direct connection I used to test the startup as per my video above. I was just asking @duncanrm how he can see problems with his glow plugs, and how it works from his dash mounted voltage gauge.

Thanks.
 
If you wanted to get fancy with an Arduino controller you could use one of these Cummins-style air intake heater relay setups.
Amazon product ASIN B00D2C1T6W
You could implement your own Super Glow-like system. One relay would supply the resistor on the intake for after-glow and the other would supply the glow plug bus bar directly for primary glow. You would use 14.5bv glow plugs just like the stock 24v super glow system.

Just an idea.
 
Thanks, yeah I quite enjoy troubleshooting and it can be very rewarding if everything works out. So you added some digital voltage monitor which is connected to your battery? How would you know if there is something wrong with a glow plug? Less drop on the voltage when you glow because one is not working? You wouldn't happen to know what relay I should get? Apparently a Ford one is good but I feel bad to put something from Ford in a Japanese car 🤣plus I am not sure if the Ford one is 24v

Thanks

I cant tell if I have dropped a single glow plug.. but I'd certainly know it from how the engine was running for the 30 seconds or so after it started.. my voltage gauge really just lets me know that the system is actually glowing, gives me a bit of an idea of the state of the battery (from the voltage drop) and would let me know if I had a significant change in the glow operation.

I suspect Adelaide, South Australia gets nowhere near as cold as the Czech Republic.. the worst I've started in is -7degC.
 
If you wanted to get fancy with an Arduino controller you could use one of these Cummins-style air intake heater relay setups.
Amazon product ASIN B00D2C1T6W
You could implement your own Super Glow-like system. One relay would supply the resistor on the intake for after-glow and the other would supply the glow plug bus bar directly for primary glow. You would use 14.5bv glow plugs just like the stock 24v super glow system.

Just an idea.
Hi,

Thanks for the suggestion. I think my electrical knowledge is too primative at the moment to be able to do something like this. Maybe it's adding too much complexity? Thanks anyway for all your help. I am currently looking for a relay for my new setup.
 
I cant tell if I have dropped a single glow plug.. but I'd certainly know it from how the engine was running for the 30 seconds or so after it started.. my voltage gauge really just lets me know that the system is actually glowing, gives me a bit of an idea of the state of the battery (from the voltage drop) and would let me know if I had a significant change in the glow operation.

I suspect Adelaide, South Australia gets nowhere near as cold as the Czech Republic.. the worst I've started in is -7degC.
I see, OK, makes sense. I would like something like that eventually. I just want to get my BJ up and running so I can get it through the MOT and drive it for a few years before I restore it.

Yeah it gets pretty cold here, we had -20 a couple of weeks ago so I want to make sure my glow is working well for that kind of weather and it doesn't cut it currently. My manual jump cable glow worked really well for my troubleshooting. Thanks for your advice and help. Enjoy your weekend, I bet you have nice weather there, it's bloody cold here this weekend.
 
I see, OK, makes sense. I would like something like that eventually. I just want to get my BJ up and running so I can get it through the MOT and drive it for a few years before I restore it.

Yeah it gets pretty cold here, we had -20 a couple of weeks ago so I want to make sure my glow is working well for that kind of weather and it doesn't cut it currently. My manual jump cable glow worked really well for my troubleshooting. Thanks for your advice and help. Enjoy your weekend, I bet you have nice weather there, it's bloody cold here this weekend.


Hi, I can surely understand your frustration, as I am in the same pickle with multiple wiring issues from the PO. I am installing a nice Ford style relay for the glow plugs. Though my glow plugs are of the 12v type. I will use my relay to function with a 24v momentary switch and supply 12v from the battery. I will be changing to 24v glow plugs eventually , but yes strongly recommend a relay and an inline fure matched to the wire. Also look at how many amps the glow plugs will be pulling and match wire and fuse accordingly. Remember the fuse is there to protect the wire..

Also make sure both batteries are equalized , meaning they both have the same voltage. Charge accordingly making sure they both come up to the same voltage, does make a huge difference.

Hope this helps..

Ohh BTW do you happen to have a part number for your 24v glow plugs ?
 
Hi, I can surely understand your frustration, as I am in the same pickle with multiple wiring issues from the PO. I am installing a nice Ford style relay for the glow plugs. Though my glow plugs are of the 12v type. I will use my relay to function with a 24v momentary switch and supply 12v from the battery. I will be changing to 24v glow plugs eventually , but yes strongly recommend a relay and an inline fure matched to the wire. Also look at how many amps the glow plugs will be pulling and match wire and fuse accordingly. Remember the fuse is there to protect the wire..

Also make sure both batteries are equalized , meaning they both have the same voltage. Charge accordingly making sure they both come up to the same voltage, does make a huge difference.

Hope this helps..

Ohh BTW do you happen to have a part number for your 24v glow plugs ?
Hi graymudder,

thanks for your tips. So I have a bunch of wires, relay and glow light prepared for installation, I am also working on a wiring diagram so I can share it once I know its all working. I have a 100amp fuse for the wire between the relay and the positive terminal on my battery. My first plan was to use a momentary switch but since the anti-clockwise glow twist still works I want to use this as my momentary switch which then triggers my new relay to start the glow and also lights a small light I will have on the dash. I like this and it feels more elegant and more like the original setup.

I currently still have the 21.5v plugs in that I purchased new a month or so ago, these worked great in my jump lead glow so I will keep them for now and I have been told they should be fine. I have the part number for the 24v ones, they are actually 23v.

21.5v part number:
OEM 19850-68040
Mine, Denso: DENSO 8717613002810

If I get 24v ones
23v part number:
OEM 19850-68020
DENSO 8717613002759

Also from another post here these should be OK too:
EIKO GT213
Bosch GPT213, HKT PT108, MAY PT108, JKT PT108

Thanks, nice to be able to help out and give back a bit. I will read your other post I see has popped up as a similar thread.

Stuart.
 
Hi graymudder,

thanks for your tips. So I have a bunch of wires, relay and glow light prepared for installation, I am also working on a wiring diagram so I can share it once I know its all working. I have a 100amp fuse for the wire between the relay and the positive terminal on my battery. My first plan was to use a momentary switch but since the anti-clockwise glow twist still works I want to use this as my momentary switch which then triggers my new relay to start the glow and also lights a small light I will have on the dash. I like this and it feels more elegant and more like the original setup.

I currently still have the 21.5v plugs in that I purchased new a month or so ago, these worked great in my jump lead glow so I will keep them for now and I have been told they should be fine. I have the part number for the 24v ones, they are actually 23v.

21.5v part number:
OEM 19850-68040
Mine, Denso: DENSO 8717613002810

If I get 24v ones
23v part number:
OEM 19850-68020
DENSO 8717613002759

Also from another post here these should be OK too:
EIKO GT213
Bosch GPT213, HKT PT108, MAY PT108, JKT PT108

Thanks, nice to be able to help out and give back a bit. I will read your other post I see has popped up as a similar thread.

Stuart.


Thank you I will see if I can source them locally. Get some pics posted once you have it completed..
 
This helped me with my own issues. I could not find solid info on where the pre-heater relay was located and found this thread. I re-seated the plug in the relay, turned my key... lo and behold; I got glow.
 
This helped me with my own issues. I could not find solid info on where the pre-heater relay was located and found this thread. I re-seated the plug in the relay, turned my key... lo and behold; I got glow.
Hi LeftHandRev,

glad it helped you. I also created a separate thread that I linked below on my new glow wiring that I now have installed. That might be of interest for you also:

Kind regards.
 

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