Which plugs should I be running - B, 2B, 3B, H and 2H diesels (2 Viewers)

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Glowplug selection seems to be a common issue amongst many owners of classic indirect-injection diesel landcruisers.

While glow plug manufacturers/distributors put out "selection catalogs", most of these catalogs have accumulated numerous errors.

So as a solution, I've tried to put together an alternative selection method as a trial.

Models affected:
BJ40, BJ41, BJ42, BJ43, BJ44, BJ45, BJ46 (running B, 2B or 3B engines depending on the model)
BJ60 (running the 3B engine)
BJ70, BJ73, BJ75 (running the 3B engine)
HJ45, HJ47 (running the H or 2H engine respectively)
HJ60 (running the 2H engine)
HJ75 (running the 2H engine)

My selection method here is based on my belief that, apart from a few minor exceptions, these cruisers can use just 6 glow plugs in all. And I believe which one an individual cruiser should use depends simply on the battery power supply available (whether 12 or 24 volt) and on which type of pre-heat system is fitted. (Glow Controller, Fixed Delay, or Super Glow)

Anyway, here is my selection guide (from which I hope you can select the correct plug for your indirect injection diesel landcruiser):
Guide to glow plug selection

BTW - The yellow type signifies "24 volt cruiser information".


12 Volt

Glow controller 8.5V
Toyota 19850-68030, NGK Y-128T, Denso DG234
APS 5013, EIKO GT208, JKT PT104, MAY PT104
Bosch GPT208, VSP PT104, Champion CH121, HKT PT104
Warning! While these plugs are CLAIMED to be equivalent to each other - their current-draw does vary from brand to brand and so unfortunately some of them may not glow your Controller properly!!! (See post #54 for further information.)

Here reduced-voltage is fed to the glowplug busbar via a dash-mounted glow controller during pre-heating. This glow controller (which consists of a coil of resistance-wire behind a viewing hole) gradually brightens to "red-hot" (or even to "bright orange" depending on the model) after 15 to 20 seconds to give a visual indication that your plugs are hot enough for you to start cranking your engine.

Fixed delay 10.5V
Toyota 19850-68010, NGK Y-147T, Denso DG232
Bosch GPT218, Champion CH133, HKT PT 145

Here the busbar receives approximately the full battery voltage during pre-heating (because no glow controller or other type of resistor is fitted upstream). There is a glow-light (pre-heat light) on the dashboard that illuminates during pre-heating and extinguishes after a fixed time delay of between 15 and 20 seconds to tell you when to start cranking.

Owners often create a similar set-up that requires the same plugs (where the busbar again gets connected directly to the battery without any resistance device fitted inbetween) when their factory-wired pre-heating systems become troublesome. In such cases the dash-mounted momentary switch used to manually energize the glowplug busbar is commonly referred to as a “Wilson Switch”. And because no timer is used, the driver must estimate the pre-heat duration themselves.
A big advantage here is that the Wilson Switch allows the driver to smooth out a rough cold-idle by providing "After Glow". (The Wilson Switch can be used to re-energise the busbar once the engine is running.)

Super glow 6V
Toyota 19850-68050 (or 68051), Denso DG220
Bosch GPT214, Champion CH125, HKT PT146

Here the Toyota engineers sped-up the pre-heating procedure by using faster heating plugs (lower voltage plugs). They also installed two stages of pre-heat, and automated both these pre-heating durations according to coolant/block temperature and other factors. The first stage connects the busbar directly to the battery (12V) and the second stage (after-glow) drops this voltage to somewhere close to the plugs nominal voltage (6V).
Like the "Fixed Delay system" there is again a glow light (pre-heat light) that is extinguished to tell you when to crank. However here it illuminates for a much shorter time. (Typically just 2 or 3 seconds.)


24 Volt

Glow controller 20.5V
Toyota 19850-68040, NGK Y-178T, Denso DG235
Bosch GPT207, Champion CH122, HKT PT109
Warning! While these plugs are CLAIMED to be equivalent to each other - their current-draw does vary from brand to brand and so some of them may not glow your Controller properly!!! (See post #54 for further information.)

Here reduced-voltage is fed to the glowplug busbar via a dash-mounted glow controller during pre-heating. This glow controller (which consists of a coil of resistance-wire behind a viewing hole) gradually brightens to "red-hot" (or even to "bright orange" depending on the model) after 15 to 20 seconds to give a visual indication that your plugs are hot enough for you to start cranking your engine.

Fixed delay 23V
Toyota 19850-68020, Denso DG233, EIKO GT213
Bosch GPT213, HKT PT108, MAY PT108, JKT PT108,

Here the busbar receives approximately the full battery voltage during pre-heating (because no glow controller or other type of resistor is fitted upstream). There is a glow-light (pre-heat light) on the dashboard that illuminates during pre-heating and extinguishes after a fixed time delay of between 15 and 20 seconds to tell you when to start cranking.

Owners often create a similar set-up that requires the same plugs (where the busbar again gets connected directly to the battery without any resistance device fitted inbetween) when their factory-wired pre-heating systems become troublesome. In such cases the dash-mounted momentary switch used to manually energize the glowplug busbar is commonly referred to as a “Wilson Switch”. And because no timer is used, the driver must estimate the pre-heat duration themselves.
A big advantage here is that the Wilson Switch allows the driver to smooth out a rough cold-idle by providing "After Glow". (The Wilson Switch can be used to re-energise the busbar once the engine is running.)

Super glow 14V
Toyota 19850-68060, NGK Y-197R, Denso DG222
Bosch GPT217, Champion CH104, HKT PT141

Here the Toyota engineers sped-up the pre-heating procedure by using faster heating plugs (lower voltage plugs). They also installed two stages of pre-heat, and automated both these pre-heating durations according to coolant/block temperature and other factors. The first stage connects the busbar directly to the battery (24V) and the second stage (after-glow) drops this voltage to somewhere close to the plugs nominal voltage (14V).
Like the "Fixed Delay system" there is again a glow light (pre-heat light) that is extinguished to tell you when to crank. However here it illuminates for a much shorter time. (Typically just 2 or 3 seconds.)



Exceptions:

Toyota lists Aug 1988 to Jan 1990 12V BJ70, BJ73, HJ60, and HJ75 cruisers as running 11V plugs (Part number 19850-64031)

Originally I had listed more "exceptions" here (copied from various plug catalogs) but my research of the Toyota EPC didn't clearly back them up.

However I suspect pre-1975/76 diesels (BJ40 & HJ45) may not comply with this guide. But even then, non-compliance may really be limited to simply pre-June 1973 HJ45 (H) models ---- My research isn't conclusive.


Note:
If anyone at all (not just the owners of pre 1975/76 diesels) finds their engine doesn't run the plugs in this guide ... then PLEASE add a post to this thread so we can work out why (and so we can have real evidence for others to take note of).

This thread is basically about "factory wiring". But even if a previous owner has tampered with it, I'm hoping information here will still offer useful guidance.

As far as I know, all of the very early diesels ran "Glow Controller pre-heat" and this form of pre-heat ceased for most models in late 1982 (but may have remained in some till late 1984) when Fixed Delay and Super Glow took over.



:cheers:
 
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Cleaned.
great help.

VT
 
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Hard to read Lost Marbles

Anyway you can post the sheets in a PDF or in a word pad?
Then if someone wants to post in a pretty jpg.

VT

This looks like great info , not bitching there..

VT

Yeah. I wasn't happy with it either VT so I've now revamped it all.

I've tried to double-check all the information I've supplied there but I may still have errors. It is hard because so much information out there is FULL of errors already. And even the Toyota EPC has errors that can easily mislead.

:cheers:


And thanks for the feedback VT
 
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Tom,

If you can email me your source files, I can convert them to a nice clean JPG/PNG file... or even a downloadable PDF for you to upload.

Kraig @ Colorado . net is an easy one to reach me on...
 
Thanks to people who have been helping me privately on this.

This morning I removed the stuff on "plug-type" (which I now think would cause more confusion than it is worth if it remained there) and I made a few other changes too.

Here's a pic of a glow controller on a 1978 BJ40 (thanks to Rudi/BJ40Green):

Glow controller on.JPG

And here's another one he also supplied of a factory-installed "manual pre-heating control switch" (momentary-switch):

IMG_7838.JPG

:cheers:

PS. Basically my personal area of knowledge is limited to BJ series and even then .. just the 40-series within that grouping. So while I am trying here to extrapolate my BJ4# knowledge to a much wider range of models/vehicles (ie ALL #B and #H powered cruisers) .... I'm still undecided on whether it is appropriate/useful to attempt to do so. But I suspect it will be.
Glow controller on.JPG
IMG_7838.JPG
 
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Wow, nice work marbles!!

Now what will we argue about?!?! Oh, we still have the diesel-badge-location debate, phew!
 
Awesome Lostmarbles.

So I have Superglow apparently. (1985 HJ60)
Going off the volt meter, I think they glow at 6 volts for about 2 seconds, and then after glow for a bit longer, the time depending on the temperature, at 3 volts think. Is that correct?
 
Are you sure about the superglow part numbers for Bosch?

On this website http://www.bosch.com.au/content/language1/downloads/Bosch_Glow_Plug_Web_Ready.pdf it says:

HJ60 10.82 - 08.87 6 4.0 2H Chassis HJ60V 12V GPT-228
HJ60 08.87 - 08.88 6 4.0 2H Chassis HJ60V 12V GPT-217

Thanks Darthvincor

I had a quick squizz at this Bosch pdf document just now and it seems to be full of faults just the same as the older Bosch catalogue I have at home.

For instance, if you look on the Landcruiser page you'll see that they've even got GPT217 listed there as being both a 12V plug and a 24V plug on the very same page. That shows they haven't even proofread what they've written.

But the computer I'm on at the moment is rather unfriendly ... I'll have a better look at that pdf file tomorrow to see if it confirms any mistakes on my part.

:beer:

PS. And thanks Amaurer & Baas for the kind words.

Edit:

Spent more time on this horrid computer just now trying to view that pdf and I've just confirmed that the following two lines that you've correctly uplifted from that pdf are indeed nonsense. This catalogue itself elsewhere lists GPT217 as a 14V plug and GPT228 as a 23V plug so neither plug can be used at all on a 12 volt cruiser!
HJ60 10.82 - 08.87 6 4.0 2H Chassis HJ60V 12V GPT-228
HJ60 08.87 - 08.88 6 4.0 2H Chassis HJ60V 12V GPT-217
 
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OK I've downloaded that newer Bosch pdf file at home now.

Here are the old and new catalogue sections together showing their landcruiser #B and #H information:

BoschOld.jpg
BoschNew.jpg

As well as mixing up their 24V and 12V plugs, they've never managed to get their BJ42 information correct in either catalogue.

Since when did any BJ42 run "fixed delay" plugs? They either ran "glow controller" or "superglow" plugs to the best of my knowledge. (Please tell me if you know otherwise.) Edit: Maybe in some part of the world the BJ42 got Fixed Delay pre-heat?

And I have no real expertise in 60 series, 70 series or the HJ series as a whole ... etc ...So heaven only knows what mistakes are there.

It's errors from reputable manufacturers like this that are responsible for so many Internet vendors giving the wrong advice too!

So the upshot of all this is .... I see no reason at this stage to alter post #1 further ... as a result of reading this bosch pdf but I am reliant on owners of 60-series, 70-series, HJ-series etc cruisers to check that their 3B, 2H (or whatever) engine is running plugs that match my post #1 .... And if they don't .... let's discuss why here?

But I have at least worked out from this exercise that the new number for Bosch 6V Toyota plugs is 0-250-202-115 so I'll drop that into post #1 now :)

:cheers:

Actually even that surpises me with Bosch.... Why have a catalogue giving old and new part numbers separately for the same part! Sheesh!

Oh - and here's another pic of a BJ40 dash (and sorry for the bias towards BJ40s here.... I wonder why I do that?) .... showing a pre-heating momentary-switch that is being used in conjunction with a glow controller. (BTW - The switch is part number 84521-60010 .. thanks to Rudi's research ... I couldn't even find it on my epc copy ..and it is used to re-energise the Glow Plug Relay manually as-required to even out rough idle in those atrociously-cold climates that some strange people choose to live in. :D)

BJ401279sabretooth2.jpg

(Thanks to Sabretooth for providing the original photo on MUD)
BJ401279sabretooth2.jpg
BoschOld.jpg
BoschNew.jpg
 
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Awesome Lostmarbles.

So I have Superglow apparently. (1985 HJ60)
Going off the volt meter, I think they glow at 6 volts for about 2 seconds, and then after glow for a bit longer, the time depending on the temperature, at 3 volts think. Is that correct?

Sorry. Forgot to attempt to answer this.

Looking at the EPC it appears that 12V HJ60s in some markets (not all) in 1985 did indeed get "super glow" (with 6V plugs).

However I would have expected to see double those voltage readings ... but then I'm unfamiliar with Super Glow.

(ie. At this stage I would have expected around 12V being applied in the first stage and then around 6V for the second stage. But I intend to research better answers for this further down the thread when I'll look at wiring diagrams for each type of pre-heating system.)

Would someone more knowledgeable/experienced in "12 volt super glow" like to comment on this at this stage?
 
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Thanks for the replies Lost.

I had a suspicion there might be some errors in the Bosch list. (Bosch of all people)
For example, I always thought the 2H was used in Dynas and Coasters, yet on the Bosch list there are no H engines at all. (maybe they don't go back that far)

I too have no idea how my particular glow plugs work. I'm not even sure if I'm supposed to crank at the super or after glow.
 
:hmm: It would surely be nice if someone from Bosch would post here and explain the many problems with their catalogues. (But I don't think that's likely.)

I'll mention another anomaly.... Both GPT213 and GPT228 appear to the very same plug (at least according to Bosch's own data)

And I don't like some of the plug dimension specs Bosch attribute to some of their Toyota plugs either. (Some don't seem to fit "Standard Toyota Specs")

And while on the subject of errors, here one from the Toyota EPC that has caused members on this board grief in the past.
68030 plug is mistakenly labelled by Toyota themselves as being 6V. (See the red underlining) ...

EPCerror.jpg

And now instead of looking at errors, have a look at a much better catalogue (provided by Karmot/HKT in this part of the world):

HKT1.jpg
HKT2.jpg


I have far more confidence in this one!

:cheers:
EPCerror.jpg
HKT1.jpg
HKT2.jpg
 
Tom, excellent job! :clap: Well done! :clap:

Rudi
 
And now instead of looking at errors, have a look at a much better catalogue (provided by Karmot/HKT in this part of the world):

View attachment 508848
View attachment 508849


I have far more confidence in this one!

:cheers:

As far as I can tell that one reproduces the same errors as far as the BJ42s are concerned.

There is no BJ42 listed which takes an 8.5V plug, for example...
 
As far as I can tell that one reproduces the same errors as far as the BJ42s are concerned.

There is no BJ42 listed which takes an 8.5V plug, for example...

Ya got me there Drew! .....:eek:

But at least they have the 24V equivalent (20.5V) there ;)

Now give me another HKT error then........... Go on...............




Edit: Hope you don't try too hard... cos I bet they haven't got all the production periods (linked to the plugs) correct. But at least HKT mistakes aren't so blatently obvious to everyone (including to completely inexperienced people).
 
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Hi folks.

I'm interested in the different pre-heating/starting procedures now because explaining these will help owners identify what type of pre-heating system they have.

I can obviously describe the "glow controller procedure" because that's what I've got. So here goes with that - based on my own experience...........

Start key-switch for a "Glow Controller pre-heating system":
GlowController.JPG

Pre-heating/Starting Sequence - glow controller (8.5V or 20.5V plugs)
With the gearbox in neutral (and your foot on the clutch when you're cranking in case you're having a brain fart and really have it in gear) ...you:
  • insert your key
  • turn it fully anticlockwise (against spring-pressure) to the "glow" position and hold it there for 15 to 20 seconds waiting for the glow controller to glow red/orange
  • turn the key (when glowing brightly) fully clockwise to the "start" position to crank the engine
  • release the key (as soon as the engine has fired up) whereupon internal spring pressure will put the key in the "on" (or "motor run") position
  • use either the accelerator pedal or hand throttle to maintain a slightly higher-than-normal idle for a while (say 20 seconds to a minute usually if the engine is cold) until the engine runs smoothly and feels responsive
  • and in "24V cold-climate models" you have one further operation at your disposal ... you can hit the "dash-mounted momentary switch" to re-heat your glowplugs (and re-glow your glow controller) in order to smooth out rough-idle in freezing conditions

Start key-switch for a "Fixed Delay pre-heating system":
IgnSwitchFixedDelay.jpg

Pre-heating/Starting Sequence - fixed delay (10.5V or 23V plugs)
With the gearbox in neutral (and your foot on the clutch when you're cranking) ...you:
  • insert your key
  • turn it clockwise (against spring-pressure) to " the "glow" position at which point the glow light (pre-heat light) on the dash should illuminate.
  • when the light extinguishes (after a delay of approx. 15 seconds), turn the key further/fully clockwise to the "start" position to crank the engine
  • release the key (as soon as the engine has fired up) whereupon internal spring pressure will put it back in the "on" (or "motor run") position
  • use either the accelerator pedal or hand throttle to maintain a slightly higher-than-normal idle (if necessary) to get the engine running smoothly and feeling responsive

Start key-switch for a "Super Glow pre-heating system":
DarthVincorHJ60.jpg

Pre-heating/Starting Sequence - super glow (6V or 14V plugs)
With the gearbox in neutral (and your foot on the clutch when you're cranking) ...you:
  • insert your key"
  • turn it to the "on" position and verify that the "glow indicator light" (or "Pre-heat light" in the above photo) has come on to commence the 1st stage (fast-heat stage) of pre-heating
  • when the light is extinguished (which most often takes just a couple of seconds on the first start of the day but can take anywhere from 1 to 9 seconds depending on coolant temperature), turn the key clockwise (against spring-pressure) to the "start" position to crank the engine
  • release the key (as soon as the engine fires up) whereupon internal spring pressure will put it back in the "on" position and the Super Glow system will automatically continue to apply further pre-heating (more-correctly called "After Glow" now) lasting anywhere from 10 seconds to 2 minutes to keep the engine idling smoothly till it warms up.

Note: If you read Owner Manuals published by Toyota you'll see they talk about holding the accelerator pedal either half-way down or fully down while cranking. In my experience this is largely unnecessary. On my cruiser the EDIC (electric diesel injection control) puts the injection pump in the overinject/overfuel position so she fires up with a big puff of black smoke without having to do that. (Once it's fired up I do adjust the revvs with the pedal though.) But if you don't have EDIC on your cruiser (and some don't) then you may indeed have to hold the accelerator down somewhat.
You'll also see Toyota say not to glow for more than 30 seconds with a glow controller. Well I left my "Glow Control Pre-heat" on for more than 20 minutes without any component suffering damage (when my ignition switch jammed in the "glow" postion while I was working on the steering column without having disconnected my battery).
:beer:
IgnSwitchFixedDelay.jpg
GlowController.JPG
DarthVincorHJ60.jpg
 
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Constructive Criticism (Plug Catalogs)

In reference to Bosch specifying GPT217 and GPT228 (14V and 23V respectively ) plugs for 12V cruisers - I wonder if any diesel engine anywhere in the world has ever successfully run glowplugs that have a higher voltage rating than the battery system available to run them? (I hear a whisper that at least one person at Bosch Australia is still not certain they’ve made an error.)

Ideally, all criticism should be constructive. So bearing this in mind, let’s do some research to offer Bosch “a fix” on their two 12V HJ60 errors (without looking much further into their catalogue at this stage to see exactly how many other errors there are).

Let’s check out what Toyota specifies for an HJ60:

HJ60TSpecs.jpg

So from this, we can see Toyota are saying their 12V HJ60 landcruisers left their factory fitted with 68050/68051 (6V) plugs between Oct 82 and August 87 while some of the same vehicles left with 68010 (10.5V) plugs (depending on “market destination”).
(Bosch please note … No 12V HJ60 landcruisers at all left the factory with either 14V or 23V plugs.)

With the “global-transfer" of classic vehicles like these, I believe no plug manufacturer should “bury their head in the sand” by trying to cover only those vehicles sold new in their country. (Keeping track of which ones weren’t sold new gets increasingly difficult as time goes by anyway!) So bearing this in mind, I suggest Bosch solve their dilemma by inserting the Toyota terms “super glow” and "fixed delay", perhaps like thus:

HJ60 10.82-08.87 6 4.0 2H Chassis HJ60 12V GPT214 (super glow)
HJ60 10.82-09.87 6 4.0 2H Chassis HJ60 12V GPT218 (fixed delay)

But even giving production time-lines (eg. 10.82 - 08.87 above) for these old classic cruisers (what with sellers and buyers ensuring their ongoing global-transfer) is fraught with danger .... Because when you're dealing with the WORLD scene .... those dates can vary from market to market (and even Toyota couldn't keep up with it in their archives). So searching Toyota's database (their EPC) further and in a slightly different way I get variations. For instance it tells me a 12 volt HJ60LGKRC model was still receiving Fixed Delay plugs .. ie. GPT218-equivalent plugs... up until 08.88!

If any plug manufacturer does choose to insert the terms Glow Controller, Fixed Delay and Super Glow in their catalogue, then they'll need to add some sort of footnote too. It could perhaps refer customers to their Toyota Owners Manual or “Landcruiser-specialist Websites” (perhaps even mentioning ih8mud since it is the leader here) for further information if they’re unsure which pre-heating system they have.

I know this isn’t an ideal solution for a plug manufacturer (who will want their catalogue to “stand-alone”) - but surely it is infinitely better than feeding customers nonsense as they’re inadvertently doing now.

And lets help both HKT and Bosch with a “12V BJ42 fix”. (This fix is particularly important considering the high number of BJ42 cruisers “sold new and still existing” in both Australia and New Zealand and considering their high value for restoration purposes!)

Here’s what Toyota specifies:

BJ42TSpecs1.jpg
BJ42TSpecs2.jpg

So here’s the fix I offer for 12V BJ42 cruisers (based on the new Bosch catalogue format):
BJ42 08.80-10.82 4 3.4 3B Chassis BJ42 12V GPT208 (glow controller)
BJ42 10.82-10-84 4 3.4 3B Chassis BJ42 12V GPT214 (super glow)

(Ignoring the problems already mentioned with "production dates".)

:cheers:

PS. I do hope I haven’t dropped too many mistakes into my recommended "fixes". (That would certainly be embarrassing when I’m criticizing someone else’s mistakes! He he.)

And BTW -…I admit I’ve been a little too harsh in my criticism of the Bosch catalogue. Really I can easily see how misunderstandings occur regarding vehicles that are decades old and I’ve already acknowledged that Toyota themselves have published incorrect data that misleads people. Furthermore, I’ll bet there are other catalogues from other manufacturers (that I haven’t yet seen) that contain even more errors. And furthermore, I'm having a hell of a hard time writing all this and getting it right too!
HJ60TSpecs.jpg
BJ42TSpecs2.jpg
BJ42TSpecs1.jpg
 
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