I guess this explains the hard-starting on my B diesel!

[Falco80]

Well, i replaced all four glow plugs on my 79 BJ40 today. Looking at the state of the plugs i pulled, i guess it's glad i did! Plugs #2 & #4 were blown out on the tip.

Now it doesn't get very cold where i live, compared to some places you guys reside. The lowest it has been is maybe 5 deg C overnight. I've had this truck 2 months and when i used to start it it would take a long glow and then splutter and belch out smoke until it would settle down and eventually idle smooth. My glow-controller never did "glow" red at all through the little screen, but it did get hot to touch.

So, i bought a set of 8 volt plugs and put them in. Al the stampings on these plugs are the same as the ones that i pulled out, so maybe they've been changed in the past. I'll check tomorrow on their performance and i hope it's all good.

My questions are:-
1. Does excessive "glowing" cause the glow plugs to blow out like this? Like if you glow for a minute or so, would it do this to the plugs?

2. I don't know when, if ever, these plugs have ever been replaced but i'm sure they would have a finite service life. What sort of lifespan do you think a set of glow plugs have?

3. With #4 plug being stuffed, does that mean power was even getting to the other 3 plugs?

Thanks for any explanations!

 

[roscoFJ73]

Pretty.
The factory denso glow plugs in my 75 are 14 years old and have done 240000klms.
The JKT are supposed to be ok,I have them in my 73 series.

Did you check that the Dyna plugs and BJ40 use the same voltage? I imagine they do,but some landcruisers use different voltage.

Whats the red stuff on the thread of number 2 ? .Looks like red dust solidiified

 

[Dieseler]

Looks like you may of had the wrong plugs in her and melted them...make sure you have the correct voltage plug for the engine whether 12v or 24v starting system/super glow or mannual glow.
The good ones have 8v stamped on them but dont see the volt stamped on the melted ones.

 

[lostmarbles]

Hi there Dan.

If you've fitted JKT PT93 8V plugs then I believe you've fitted the wrong plugs.

The B-engine fitted to a 1979 BJ40 should be running PT104 plugs I believe - which are 8.5V.

Fitting the wrong plugs is likely to cause damage like that (rather than glowing them for too long in the case of a BJ40 B-engine).

When you fit the wrong plugs, there is even a chance that the plug dimensions can be wrong too (as well as the plug voltage). I'll throw in some images here to show this...........

Firstly though.... here is what the EPC says....

View attachment 354460

View attachment 354461

I believe you should be running Toyota 19850-68030 plugs which are equivalent to NGK Y-128T, ND 067100-1350, APS 5013, EIKO GT208, JKT PT104, HKT PT104, MAY PT104, CHAMPION CH121

 

[lostmarbles]

There is a lot of incorrect info out there on glowplugs. And some of this stuff on the Karmot site may not be accurate too. Yet it is the BEST site I've found. Here are some images from it:

View attachment 354462

View attachment 354463

View attachment 354464


Yes. .... If this site info is correct, the L2 dimension differs between the PT93 (incorrect) and PT104 (correct) plugs by 1 millimetre. But I think it is more likely that the 0.5V lower rating will kill either your new plugs (or your glow controller) - should you attempt to glow for long periods using PT93 plugs.

PS. Ignore Karmot's info on which engines plugs are designed for - I KNOW they have innaccuracies there. And why not gpo for a good Japanese brand like HKT (which are easy to get in Oz). I'm wary of the cheap ones. (Where are JKT made? I seem to remember they are very cheaply priced on Ebay compared to other brands.)

 

[lostmarbles]

I think I'd better add this image from the EPC or you may still not believe me Dan:

View attachment 354468

This image shows that pre-1980 12V BJ40 landcruisers also use 19850-68030 plugs whereas the earlier images I posted suggested those plugs may only apply to 1980 onwards.

(Yes - There are lots of errors in the Toyota EPC glowplug data so it's little wonder suppliers tend publish incorrect information and tend to suggest people buy the wrong plugs. )

And the part number 19850-56022 is an 8.5V plug too - but I think it became obsolete and was replaced by the 19850-68030 plug. - In fact, I believe the 56022 plugs were the ones my cruiser left the factory with, and the only difference was the terminal thread was a slightly larger diameter in the 56022 design.

I suspect this plug on the left here is a "19850-56022" plug:

View attachment 354471

 

[Falco80]

Ahh, damn, then i've fitted the wrong plugs.
These were listed as glow plugs for "BJ40 B diesel Landcruiser", so i didn't think twice. They are exactly the same as the ones i pulled out so i guess i'm lucky it doesn't get below 0 deg C down here!

Would this explain why my glow-plug controller doesn't glow at all?

Thanks Tom for the informative post. I'll head down to my local auto parts place today and see if i can source the correct set of plugs.

 

[lostmarbles]

...Would this explain why my glow-plug controller doesn't glow at all?......

When "glowing" - the current flow through your "glow controller" is the SUM of the currents flowing through your individual glowplugs. (Iglow = I1 + I2 + I3 + I4)

So even if just one glowplug becomes "open-circuited" - there won't be sufficient flow left (through your glow controller) from the remaining good plugs to make it glow properly.

And when the ends of a glowplug are "blown apart" like that - those plugs will certainly be "open-circuited" (and an ohm-meter will give them a reading of "infinite resistance").



PS. I've never experienced a single glowplug failure in 30 years and 250,000kms with my BJ40. And my plugs and controller survived undamaged after being left glowing for AT LEAST 20 minutes (when I was silly enough to be working on my steering column and ignition switch without disconnecting the battery first). I discovered the problem by smelling the burning paint on the dash near the controller!

 

[lostmarbles]

A quick search by me just now on the Internet reveals the largest/best-known eBay seller in Oz promoting the 8V plugs for your BJ40 Dan. So I'll bet there are more people affected by this:

View attachment 354531

View attachment 354532

I maintain that these 8V plugs are NOT the plugs your glow controller was designed to run with!

I am confident in saying this because I've owned my 12 volt BJ40 for 30 years and during that time it has ALWAYS run 8.5V plugs . And I've also long-maintained an interest in these specific cruisers..........

And 8.5V plugs are still widely available so "availability" can't be the reason they are listing 8V plugs.

While the "1mm shorter reach" may be unimportant, I believe the "0.5V lower rating" unnecessarily increases the current flow through your glow controller to put it at risk of melting during prolonged-glowing. (And WHY do that when 8.5V plugs are what such a system was designed to run with and are also what work perfectly well?)

PS. Are you saying you've fitted the new 8V plugs and yet your controller still wouldn't glow? If so - I'm baffled. Lower voltage plugs should make it glow faster/brighter (hence the greater risk of it burning out). If it doesn't glow with 4 good plugs that are in good electrical contact with the busbar - then this suggests things like "blown glow controller", 'incorrect glow controller" (eg 6-cylinder version fitted), etc

 

[Falco80]

G'day Tom, thats exactly where i bought these plugs from. I've bought heaps of stuff from Roodogs before and they are great to deal with IMHO. They do sound like the wrong plugs they are selling though for the B Diesel. I've never seen my controller glow before, but i hear the relay click and assume it is working because the controllers wire coil does get very hot to touch. I have a spare here that came with the truck so i might swap them over and see. I've also got the B & 2B Toyota Manual here so i'll do some investigating with a multimeter. I don't like electrikery!!

I enquired about some 8.5V plugs at my local REPCO store and and they came up with a Bosch plug that sells for around $20Aus each. Would that be right, or too expensive? I've ordered them in and i'll eyeball them before buying.

Many thanks for the info Tom!

 

[lostmarbles]

Here's a pic of my glow controller glowing with 8.5V plugs Dan:

View attachment 354572


Does yours look like this? (Except for your "lack of glow".)

And if my useless maths is correct, reducing the plug rating from 8.5V to 8V increases the glow controller current by 6% (which may be enough to blow it IMO!)



PS. I know Roodogs are good people to deal with and I buy off them myself. They go to a lot of trouble to sort out "customer-satisfaction issues". But I just think they've made a mistake here in their background research. And when you look at the sheer size of their "eBay operation" such mistakes must be inevitable. And those of us with B-engined forties are indeed a rare-breed so I imagine they wouldn't deal much in "B-engine-specific spares"

And I seldom notice seller-mistakes because I always research the exact part number I want without relying on their help.

PPS. How do you feel your glow controller coil heating? It should be inaccessible for touching?

 

[Falco80]

Hi Tom, I did some experimenting when i first bought the shorty and it involved having the controller detached from the dash, but still wired-up. I was trying to see if it glowed at all because i saw that picture of yours glowing in another thread and was trying to get mine to do the same. Let me just say that it gets hot, damn hot!

Roodogs are great, and i agree it must be hard as these little B diesels are a lot scarcer than their big-brother 3B's.

Here's the spare controller i have. It has a stamping on it that appears to be Nippondenso?
The part numbers's are stamped on it are:
067200-0230
and
28550-46021

Is there any way to tell the differance between 6-cylinder and 4-cylinder versions? Does your parts program have the details?

 

[rockcrawler]

That's the same as mine Dan, except for the "7 B", mine is a "7 Q". Most likely just a production line/date stamping.

 

[lostmarbles]

...Here's the spare controller i have. It has a stamping on it that appears to be Nippondenso?
The part numbers's are stamped on it are:
067200-0230
and
28550-46021
s there any way to tell the differance between 6-cylinder and 4-cylinder versions? Does your parts program have the details? ..

That's the same as mine Dan, except for the "7 B", mine is a "7 Q". Most likely just a production line/date stamping.

I've noticed my BJ40 has 7s stamped on lots of items (including my injector bodies). And s has got to be better than B or Q because it's more advanced down the alphabet Eh?

But there's no doubt you have the correct glow controller there Dan:

View attachment 354577


If it doesn't glow well with 4 good plugs installed - then I suspect poor electrical connections somewhere - which could even be inside your glow relay - but more likely to be at your busbar.

And Bosch GPT208 plugs would be good ones I reckon:

View attachment 354578

(I'm seldom disappointed with Bosch automotive products)

The price you quoted is probably 20% too high but that is typically Repco - and may be a small price to pay for convenient access to a good brand.



PS. Another thing worth knowing about our glowplugs is that they are prone to "cascade failure". In other words, if one fails, others are likely to follow - and very quickly. This is because when one becomes open-circuited it stresses the remainder by causing more voltage (EXCESSIVE voltage) to be applied to them - making them glow hotter - even though the glow controller glows less at very the same time.

 

[lostmarbles]

Incidentally here are a couple of photos of a BJ42 (3B engine) glow controller (where the manual glow system is very similar to our BJ40 models and uses the same four 8.5V plugs):

View attachment 354581

View attachment 354582

Notice how "fully enclosed" these controllers are.

I believe Toyota did this for fear of "behind dash electrical fires". (Just a theory of mine.)

And I think this "fear of electrical fires" saw the demise of the whole "glow controller concept" shortly afterwards --- leaving us to be the lucky owners of these rare examples of "generally bullet-proof glow systems".

 

[rockcrawler]

Interesting Tom.

On mine the PO put a pen or something similar through the screen in the barrel because it no longer glowed and he wanted to take a better look inside (to see what the problem was I guess ).
I tried to replace the screen but no avail. There's a clip in there that holds it in place that is impossible to take out. So I ended up machining a whole new barrel, almost there with that, just one more operation to go on it and its done.

 

[herbs]

Couple of questions here, are the controllers still available new and does the H diesel use the same 8.5 V plugs? (but 2 more of them) The controller on mine doesn't work and erm......there's bare copper attached to one of the terminals. That's kinda bad.

 

[rockcrawler]

Is the resistor burned on it?

 

[herbs]

At some stage it's got that hot that everything there is black and crispy. Would've been exciting that........

EDIT: The H motor does use 8.5 V plugs.

 

[rockcrawler]

If the resistor wire is still in one piece you should be able to repair it.
The insulators and washers could be made up from phenolic sheet.
The resistor if burned (melted and no longer in one piece) could also be made up from nichrome wire.