Need village idiot style explanation: wilson switch and glow plug indicator

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Ok, as a new dude here is what I gleaned from forum and web searches and observations on my rig. Glow plug is an electrically heated wire that heats the combustion chambers raising the air temperature inside the chamber so that the engine can do a cold start. Apparently somewhere along the line someone installed a "Wilson Switch" on the steering column bypassing the pull string knob that sadly still sits in the dash a former shell of itself with just a nub of string where his working johnson used to be). In order to do a cold start I turn the key half way and depress the switch for approximately 30 secs then a full turn and she kicks over in a cloud of black and then white smoke. I get that the black smoke is unburned fuel and is mostly owing to me hitting the accelerator during the start procedure to help the engine get itself rolled over the first time in the day. She doesn't need that help during the day , just to get out of bed. The reason that I'm timing the readiness of the engine is that the glow plug ready indicator on the dash doesn't function. Ok now my questions. What exactly is the Wilson switch ( actually a button) supposed to do and how can I tell if it is doing it's job effectively? Are there alternatives to the Wilson switch, pros/cons? Next how is the glow plug sensor connected to the glow plugs? I understand that the screen is supposed to glow red when the engine is ready. Please someone tell me that "back in the day" they didn't just decide to connect a hot line into the engine to heat it like a toaster element and a mirror element wired right into the dash so I could know "real time" just how hot the engine really was? Or is it more like some kind of mechnical sender unit that just passed the heat directly from the engine to the glow screen giving the same real time report. Are there other indicators out now that can replace the glow screen on my dash with something that I can see or read easily?:hmm:
Thanks again for your patience guys.:cheers:
 
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Firstly - I see you've been reading HJ47s build thread today - I reckon you should be able to glean pretty well all your answers from there.

....Glow plug is an electrically heated wire that heats the combustion chambers raising the air temperature inside the chamber so that the engine can do a cold start.............

Yep. That's a very simple explanation of what they do alright. (But I think the plugs actually have some sort of inbuilt thermostat mechanism to prevent them going beyond a set temperature - Although I could be wrong here.)

.... In order to do a cold start I turn the key half way and depress the switch for approximately 30 secs then a full turn and she kicks over in a cloud of black and then white smoke.....

Interesting!

With mine I turn the key anticlockwise and wait 20 seconds for the "glow controller" on the dash to glow "bright orange". Then turn the key clockwise to engage the starter.

By the way - The white smoke is "unburnt fuel" and the black smoke is "soot" that has been dislodged from your exhaust system.

....What exactly is the Wilson switch ( actually a button) supposed to do and how can I tell if it is doing it's job effectively? .....

My understanding is that it is an "aftermarket way" of copying what "turning my key anticlockwise" does. (People install a manual switch/button on their dash to do the same job as what my key does. But with the dash switch/button - It may also be activated "while the engine is running" to smooth out a rough cold-idle.)

... how is the glow plug sensor connected to the glow plugs?.....

The Toyota name for the "dash mounted glow indicator" is "glow controller". It is wired "in series with the "parallel-wired glow plugs".

And I don't advise using the term "glow screen" for the "glow controller". Because I understand some Toyota diesels have a screen in the air intake manifold that "glows" to preheat the air entering the combution chambers. (A cheaper way of achieving cold-starts than installing glow plugs in every cylinder I guess.)

I think HJs thread gives much the same info as I've posted above. But I admit it is a long thread so it takes a lot of reading. (Or just zero-in on the part where he "fries his glow controllers". :D)

:cheers:
 
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My glow indicator

Mine is in the dash,on my BJ42.I have never seen it glow.I turn the key counter clockwise for about a 20 count and start her up .I have taken the glow indicator off and see nothing wrong ,ie it is wired up , blew out the dust if any ,put it back,no change.
 
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Mine is in the dash,on my BJ42.I have never seen it glow.I turn the key counter clockwise for about a 20 count and start her up .I have taken the glow indicator off and see nothing wrong ,ie it is wired up , blew out the dust if any ,put it back,no change.

That's very puzzling to me Joe.

As far as I can make out, this is how mine is wired up:

glowwiring.jpg

So for current to pass through my glow plugs, it must be travelling through my "glow controller" (that dash-mounted indicator coil) too.

So I don't know what the answer is there Joe.

:cheers:
glowwiring.jpg
 
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My CDN 81 BJ42 has the Glow controller (with lite bulb), the ign switch position and the dash switch as well.
When I start mine I can turn the key back and hold (which I never do!) or turn the key to the run position and hold down the dash switch until the Glow control is bright orange? Then turn to start and its runs within 2 rpms!. I can also hold the dash switch during warmup if the motor does not want to run, the smoke clears up quickly when I do this.
The later models did not have the dash switch and used a timer, The solution is, if your truck has a timer, cycle the glow plugs 2 or 3 times, or turn on the key wait for it to time out then repeat.
Btw; I won't be giving up my dash glow switch ever!

Cheers
 
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My CDN 81 BJ42 has the Glow controller (with lite bulb), the ign switch position and the dash switch as well.
When I start mine I can turn the key back and hold (which I never do!) or turn the key to the run position and hold down the dash switch until the Glow control is bright orange? Then turn to start and its runs within 2 rpms!. I can also hold the dash switch during warmup if the motor does not want to run, the smoke clears up quickly when I do this.
The later models did not have the dash switch and used a timer, The solution is, if your truck has a timer, cycle the glow plugs 2 or 3 times, or turn on the key wait for it to time out then repeat.
Btw; I won't be giving up my dash glow switch ever!

Cheers

That sounds a nice set-up Freebie. If I was in a colder climate I'd probably copy that.

:cheers:

(This is supposed to be a "subtropical climate" but it does feel damn cold at the moment. It's only about 10 oC outside! But my "20 second glow" is still fine even down to 5 or 6 oC which is about the lowest it gets where I live.)
 
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That's very puzzling to me Joe.

As far as I can make out, this is how mine is wired up:

View attachment 228533

So for current to pass through my glow plugs, it must be travelling through my "glow controller" (that dash-mounted indicator coil) too.

So I don't know what the answer is there Joe.

:cheers:

Ok then if your wiring diagram is right for my glow controller to not be lit after a 30 second count would imply that it isn't getting current to the indicator coil once the circuit is completed, i.e. its probably a wiring issue. Given that none of the other guages on my dash work either this seems a safe bet. What do you think?

P.S. HJ47's thread is long I read most all of it in almost two hours, that guy is a *****machine!!! I felt like a a first semester freshman general science major sitting in a senior level astro physics class, just watching in wonder as the prof rolled through the discussion at light speed on topics which to him seem nothing special but to me I needed a cliff notes explanation of the basics everytime he hit a new turn. I can only hope to be half as comfortable working on my rig in 10 years as he is now working with his.
 
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I'm pretty sure my BJ42's glow plug indicator light shined when glowing and when off the timed cycle was finished.

The wiring diagram would back that up - power to glow plugs runs through the light.

Missing from that diagram is the pre-heating timer.

The B, 3B, 11B, 13B, 13B-T Manual available for download here would show how it might be for your machinem but a bit much for a village idiot :grinpimp:
 
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Yes the light glows if the system is working, but it does take awhile for the light to glow and is difficult to see in the bright sunlight!
jabxyz are your glow plugs energized during the glow cycle? (voltage at the glow plug ) if none of your gauges work your dash wiring may be disconnected? or the glow relay may not be working? (you should hear a click when you activate the glow system. Also if the outside temperature is high the glow plugs don't need a long cycle to get the engine started, if its cold out most engines won't start?

Cheers
 
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..... but it does take awhile for the light to glow and is difficult to see in the bright sunlight!.........

Our problem could be that there are subtle differences between our vehicles depending on things like - which market they were destined for. (USA, Europe, Australia etc). Mine isn't difficult to see in any light (after 20 seconds of "glow"):

glow2.jpg

Ok then if your wiring diagram is right for my glow controller to not be lit after a 30 second count would imply that it isn't getting current to the indicator coil once the circuit is completed, i.e. its probably a wiring issue. Given that none of the other guages on my dash work either this seems a safe bet. What do you think? .......

..........jabxyz are your glow plugs energized during the glow cycle? (voltage at the glow plug ) if none of your gauges work your dash wiring may be disconnected? or the glow relay may not be working? (you should hear a click when you activate the glow system. Also if the outside temperature is high the glow plugs don't need a long cycle to get the engine started, if its cold out most engines won't start?...Cheers

I agree with Freebie. Check for voltage at your glow plugs while someone is attempting to "glow" them. (Joe Egolf - Perhaps you should do the same if you haven't already done so.) If my diagram applies to your vehicles, then any voltage at the plugs would imply that all the current passing through the 4 plugs is going through the "glow controller" (dash-mounted indicator) as well. (Assuming the plugs are not blown.)

Note: I suspect that if even ONE plug is blown, the current left flowing through the other three will be insufficient to show any "glow" on your dash! (Or perhaps it would cause a "dull red" glow after 20 seconds instead of "bright orange".)

The only way to check for a faulty glow plug is to remove the entire glow plug buss bar (that runs between them) and check for continuity between the connector thread (top of each plug) and the engine block with a multimeter. If any of the 4 are "open circuit" (infinite resistance) then they are blown/faulty.

(Without removing the buss bar, testing is pointless because the meter current will flow through plugs other than the one you're trying to test.)

.........Missing from that diagram is the pre-heating timer......

That's because mine has no timers installed. (1979 BJ40 - Australian market)
glow2.jpg
 
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Well I've just been through a bunch of drama with the glow controller unit in my truck, and have learned a few things along the way.

Regarding the original post and it's question about a wilson switch, a Wilson switch is any sort of normally-off momentary switch, like the counter-sprung key position 'G' on the ignition barrel rotation, whether it be forward or backwards a turn to 'G', or a switch on the dash, factory or aftermarket, that allows the operator to put current to the glow plugs any time they like, engine running or not.

The glow plug controller must be matched to the voltage of the glow plugs. Toyota used different glow plugs depending on the system. Remembering that as voltage decreases, resistance increases, the low voltage 6 volt plugs are used in trucks equipped with a timer and Superglow set up. Those 6v units glow red hot pretty much right away.

My truck has 8.5 volt plugs and the in-dash controller. For a 'Wilson switch' i am using a 60 series steering column with a 1980~81 BJ60 ignition barrel, which allows this momentary 'G' feature easily. My engine is a 2H. For all HJ47's the glow plugs were 8.5v, up until October 1982, when Superglow came out in some markets. My glow system is designed to be a 15~30 second period, a lot longer than the Superglow set up. The thing with the fully manual system that might not have appealed to Toyota in terms of attracting more customers. Like click shifting on bicycles, which Shimano pioneered in the early 1980's, the simplified system was more idiot-proof I suppose, and allowed almost anyone to get decent shifting on their bicycle without having to learn the touch as with the previous friction system. The glow plug system may have been developed for similar reasons - first all manual, with glow coil on dash, then a timer unit and a light on the dash that goes out (or turns on as the case may be), and then the same deal but with the convenience of 2 ultra brief wait time for the glow cycle (at the expense of adding some extra parts, like a second relay, current sensors, etc, which add complexity, cost, and when they die, or go wrong, diagnosis is more complicated, and parts can be either no longer available or very expensive. These are some of the reasons that the simple momentary switch is so appealing to me. No timer, no computer chips, simple to fix and diagnose for problems, it's only drawback is the wait of 15~30 seconds at cold start.

Now this same 2H engine, when installed into an HJ60, doesn't use the 'primitive' dash-mount glow controller and 8.5v plugs, but has a timer and 10.5v plugs. Without the draw of the coil in the controller in the loop, the plugs compensate by being higher voltage.

I understand some very early BJ40's had 8 volt plugs along with a controller to match that, and I've seen 11 volt plugs listed for some later models, depending upon market and year.

I think that there could be several causes for the coil on the dash not to glow. First check would be to turn the key and listen to see if the glow plug relay clicks. If it does, there should be voltage to the controller, at either wire. If the nichrome wire in the controller is broken, there would be no continuity through the controller, so that is another check, besides basic visual inspection of the piece.

If the relay clicks and there is no power to the controller, check the wiring, particularly at the glow plug relay, where the heavy wire lead runs to the controller. It will probably be a black with with a yellow stripe, or a red stripe.

If there is current to the controller after the relay clicks, and the controller itself has continuity, then the fault lies with the plugs. If the plugs are of a higher voltage than ideal, then the plugs would be glowing for a while before any sign of life appeared at the controller. When I had 10.5 v plugs in my engine by mistake, the controller coil didn't even get red until some 45 seconds had elapsed. If i kept such a set up i imagine it would lead to over-energizing the plugs, as I the controller itself wouldn't even energize.

Anyway, I ramble on.
 
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"...The glow plug controller must be matched to the voltage of the glow plugs. Toyota used different glow plugs depending on the system...
I understand some very early BJ40's had 8 volt plugs along with a controller to match that, and I've seen 11 volt plugs listed for some later models, depending upon market and year..."

Henry is there a reference manual out there that lists which the glow plug voltage for a given year? I definitely don't trust whats in the rig now, i.e. the PO didn't know what the model or year of the rig was or what any of the dash controls were supposed to do. It does not appear to me that he did any maintainance on the vehicle so I wouldn't trust that he put the right plugs in and all I'd need to do was replace them with whatever is there.

[/quote]" I think that there could be several causes for the coil on the dash not to glow. First check would be to turn the key and listen to see if the glow plug relay clicks. If it does, there should be voltage to the controller, at either wire. If the nichrome wire in the controller is broken, there would be no continuity through the controller, so that is another check, besides basic visual inspection of the piece."[/quote]

Henry, there is no click when I turn the key. It only clicks when I push the button.

[/quote]"If the relay clicks and there is no power to the controller, check the wiring, particularly at the glow plug relay, where the heavy wire lead runs to the controller. It will probably be a black with with a yellow stripe, or a red stripe." [/quote]

Henry, I was suprised to see that it in fact is connected and the heavy wire is black with a yellow stripe.



As such if I followed your very thorough explanation, if there in fact is current running to the controller after the relay clicks then the fault lies with the plugs. Assuming that I can find a way to test that bit with a multimeter then I return to the question where do I find out what plugs are the ideal voltage for my rig?

Thanks so much for that really thorough explanation. Lost marbles was right you are the man on this subject.:cheers::cheers::cheers:

P.S. Obviously I am having major issues with multiquote tonight.
 
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AJAEbj42

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My CDN 81 BJ42 has the Glow controller (with lite bulb), the ign switch position and the dash switch as well.
When I start mine I can turn the key back and hold (which I never do!) or turn the key to the run position and hold down the dash switch until the Glow control is bright orange? Then turn to start and its runs within 2 rpms!. I can also hold the dash switch during warmup if the motor does not want to run, the smoke clears up quickly when I do this.
The later models did not have the dash switch and used a timer, The solution is, if your truck has a timer, cycle the glow plugs 2 or 3 times, or turn on the key wait for it to time out then repeat.
Btw; I won't be giving up my dash glow switch ever!

Cheers

My 1981 BJ42 is the same as Freebie's. It starts after a 15-20 second glow very quickly, couple of rpms, no more. I have been told that white smoke on startup is unburned fuel, which could mean weak or non-functioning glow-plugs.
 
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well said lost marbles & henry!!
jabxyz, send or post me your vin # and I'll see which glow plugs you should have??


Cheers
 
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Well I've just been through a bunch of drama with the glow controller unit in my truck, and have learned a few things along the way.

Regarding the original post and it's question about a wilson switch, a Wilson switch is any sort of normally-off momentary switch, like the counter-sprung key position 'G' on the ignition barrel rotation, whether it be forward or backwards a turn to 'G', or a switch on the dash, factory or aftermarket, that allows the operator to put current to the glow plugs any time they like, engine running or not.

The glow plug controller must be matched to the voltage of the glow plugs. Toyota used different glow plugs depending on the system. Remembering that as voltage decreases, resistance increases, the low voltage 6 volt plugs are used in trucks equipped with a timer and Superglow set up. Those 6v units glow red hot pretty much right away.

My truck has 8.5 volt plugs and the in-dash controller. For a 'Wilson switch' i am using a 60 series steering column with a 1980~81 BJ60 ignition barrel, which allows this momentary 'G' feature easily. My engine is a 2H. For all HJ47's the glow plugs were 8.5v, up until October 1982, when Superglow came out in some markets. My glow system is designed to be a 15~30 second period, a lot longer than the Superglow set up. The thing with the fully manual system that might not have appealed to Toyota in terms of attracting more customers. Like click shifting on bicycles, which Shimano pioneered in the early 1980's, the simplified system was more idiot-proof I suppose, and allowed almost anyone to get decent shifting on their bicycle without having to learn the touch as with the previous friction system. The glow plug system may have been developed for similar reasons - first all manual, with glow coil on dash, then a timer unit and a light on the dash that goes out (or turns on as the case may be), and then the same deal but with the convenience of 2 ultra brief wait time for the glow cycle (at the expense of adding some extra parts, like a second relay, current sensors, etc, which add complexity, cost, and when they die, or go wrong, diagnosis is more complicated, and parts can be either no longer available or very expensive. These are some of the reasons that the simple momentary switch is so appealing to me. No timer, no computer chips, simple to fix and diagnose for problems, it's only drawback is the wait of 15~30 seconds at cold start.

Now this same 2H engine, when installed into an HJ60, doesn't use the 'primitive' dash-mount glow controller and 8.5v plugs, but has a timer and 10.5v plugs. Without the draw of the coil in the controller in the loop, the plugs compensate by being higher voltage.

I understand some very early BJ40's had 8 volt plugs along with a controller to match that, and I've seen 11 volt plugs listed for some later models, depending upon market and year.

I think that there could be several causes for the coil on the dash not to glow. First check would be to turn the key and listen to see if the glow plug relay clicks. If it does, there should be voltage to the controller, at either wire. If the nichrome wire in the controller is broken, there would be no continuity through the controller, so that is another check, besides basic visual inspection of the piece.

If the relay clicks and there is no power to the controller, check the wiring, particularly at the glow plug relay, where the heavy wire lead runs to the controller. It will probably be a black with with a yellow stripe, or a red stripe.

If there is current to the controller after the relay clicks, and the controller itself has continuity, then the fault lies with the plugs. If the plugs are of a higher voltage than ideal, then the plugs would be glowing for a while before any sign of life appeared at the controller. When I had 10.5 v plugs in my engine by mistake, the controller coil didn't even get red until some 45 seconds had elapsed. If i kept such a set up i imagine it would lead to over-energizing the plugs, as I the controller itself wouldn't even energize.

Anyway, I ramble on.

well said lost marbles & henry!!
jabxyz, send or post me your vin # and I'll see which glow plugs you should have??


Cheers

Freebie,
They didn't have vin numbers in this country in 1980. The following numbers together are used to register the vehicle:
Model No. BJ40LV-KO
Motor No. B0834636
Chassis No. BJ40047640
You guys are great.:bounce::bounce::bounce2:Thanks again:clap::cheers:
 
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Jabxyz,

if you look online for a downloadable glow plug catalog, you should be able to find something. I have the HKT glow catalog downloaded, and the following info comes from it:

Is your truck 12v or 24v?

If it's 12v, the only possibilities for glow plug voltages are 8v (for early trucks with 'B' engine), 8.5v (1974~10/1980, 'B' engine, and 10.5 v. (10/1981 onwards, 3B engine).

If it's 24v, then the glow plugs are variously 19v, 20.5v, 14v (Superglow), or 23v, depending upon application.

If you pull a glow plug, you may be able to make out in the fine print on the side of the barrel what the voltage rating is. It's usually stamped onto the side of the case.
 
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No Luck

Well I tried to look up the part numbers, voltages ets in my EPC, but the listings only have part numbers. There are no corrosponding voltages with the part number and your model shows up in the mix of model types, but does not seem to show up when the glow part numbers are pulled up?? or there is no BJ40 listed with the 4 or 5 different glow plugs. It may be that I don't know how to use my EPC properly yet? or because its a non North American model?

Sorry!
 

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