HELP! HJ45 Glow Plug Controller heating too fast (1 Viewer)

[bj40green]

Maybe I was not clear with what I meant.
You bench tested each glow plug on a 12V battery a few days ago.
I like you to do the same test but now with the amp meter in series connected or if it's a clamp meter with the clamp around one of the battery cables.
This way we can figure out how much current each plug draws and if there is a bad one in the nest which is causing the trouble.

That busbar is flowing in the air. No need to wrap it.

Wait with ordering new plugs until we have this riddle solved. Plugs ain't cheap.
If the plugs are okay and we can't solve the controller problem you can keep the plugs and bypass the controller which makes that you have a "Wilson switch" set up. The same situation as before all the trouble started.

Once we have figured out if all the glow plugs are good (or not) we can concentrate on the controller.
I have the idea that, as Tom mentioned before, that there is a production or labeling problem because Mud member Jesper has the same problem with the same controller.

Tom....... are you there? What do you think?

Rudi

 

[RufusTheDufus]

Just for testing purposes, install the plug with the cracked insulator in the cylinder at the front of the engine. Bend the bus bar up so it doesn't make contact. Test it with 5 plugs to see if you still get Chernobyl response times.

 

[athensrep]

Thanks guys. I'll try out your suggested methods this evening.

In the meantime, have any of you seen this? Interesting as it looks quite reliable, cheap and easy to troubleshoot. I'm liking the individual wires/fuses to each glow plug.

http://vincewaldon.com/index.php?option=com_content&task=view&id=30&Itemid=28

I'm a sucker for making this rig as simple as possible within reason.

 

[lostmarbles]

....I have the idea that, as Tom mentioned before, that there is a production or labeling problem because Mud member Jesper has the same problem with the same controller.

Tom....... are you there? What do you think?

Rudi

Hi Rudi.

I couldn't solve Jesper's problem so I've sort-of been staying out of this one.

With the age of the HJ45 model (and "lost expertise" relating to it), I think it is certainly conceivable that a slip-up may have occurred somewhere in the parts supply system (even if this controller carried full "genuine Toyota replacement part" status and came from an official Toyota dealer parts counter). So on this basis (and if the wiring of this HJ45 hasn't been tampered with) then I do think the new controller could be a mis-match.

(I think I'm right in saying that both Jesper's and Athenrep's controllers are recently acquired replacements so perhaps they came from the same warehouse/batch.)

With such old vehicles I think we are lucky to get such specialist parts at all so I have some sympathy for the plight of the parts suppliers. (Fancy keeping such a spare part available 35 years after that model ceased production and where even the technology behind the part became obsolete many years ago.)

I haven't heard of a glow plug fault where the plug draws much more current (has much lower resistance) than it should but I guess it is possible that one of these 10.5V plugs is such a rogue plug... So it is good to rule that out.

I'm a fan of the old "manual glow with glow controller" so I like the idea of keeping this system. I think if I was in Jesper's or Athenrep's shoes I'd be researching the type of wire used in these controllers and sourcing some of it to experiment with. (It would be easy enough to setup a model preheat system using a 12V battery, six 8.5V plugs and the controller. ... Then vary the length of wire used in the controller so that it reaches full glow in around 15-20 seconds (and still doesn't look like melting even if the glow-time is extended beyond that).

The wire should be easy enough to coil yourself if you take care and wind it on some rod...

 

[lostmarbles]

Thanks guys. I'll try out your suggested methods this evening.

In the meantime, have any of you seen this? Interesting as it looks quite reliable, cheap and easy to troubleshoot. I'm liking the individual wires/fuses to each glow plug.

http://vincewaldon.com/index.php?option=com_content&task=view&id=30&Itemid=28

I'm a sucker for making this rig as simple as possible within reason.

All those fuses are silly in my opinion.

A "Wilson Switch set-up" (without the glow controller) using heavy-gauge wiring and heavy-duty relay and the existing busbar (and 10.5V plugs) would be simpler, neater and more reliable than having all those fuses if you really want to give up on having a glow controller. (You could then just have a light on the dash to show when your preheat is energised ... or perhaps that comes on via a timer after 15 seconds have elapsed if you don't want to count in your head... or whatever.)

 

[bj40green]

There is another option if the plugs turn out good.
Buy the 28550-47040 controller with the 8.5V plugs.
This is the same controller but now with a closed housing used in the HJ47.
Looks like this:


Rudi

 

[lostmarbles]

There is another option if the plugs turn out good.
Buy the 28550-47040 controller with the 8.5V plugs.
This is the same controller but now with a closed housing used in the HJ47.
Looks like this:
View attachment 874369

Rudi

Good thinking Rudi.

 

[athensrep]

Plugs turned out to be OK. Also, I placed the plug with the cracked rubber grommet (insulator) closest to the busbar wire, bent the busbar up so it wasn't touching, and hooked up the remaining 5 glow plugs. It took the controller a second or two longer to glow white hot. For kicks, I hooked the busbar to four plugs and it added a couple more seconds. I got down to two plugs hooked up to the busbar which took the controller a grand total of 10 seconds to start glowing red-hot.

I checked and rechecked all wiring under the dash and underhood. All looks well.

Could this be the relay and is it time to try a heavy duty NAPA style relay? Again, when I attempt to crank the HJ, the controller starts to glow like hades.

What am I missing? Thanks.

 

[lostmarbles]

Plugs turned out to be OK. Also, I placed the plug with the cracked rubber grommet (insulator) closest to the busbar wire, bent the busbar up so it wasn't touching, and hooked up the remaining 5 glow plugs. It took the controller a second or two longer to glow white hot. For kicks, I hooked the busbar to four plugs and it added a couple more seconds. I got down to two plugs hooked up to the busbar which took the controller a grand total of 10 seconds to start glowing red-hot.

I checked and rechecked all wiring under the dash and underhood. All looks well.

Could this be the relay and is it time to try a heavy duty NAPA style relay? Again, when I attempt to crank the HJ, the controller starts to glow like hades.

What am I missing? Thanks.

A fault with your glow relay would reduce your preheat current whereas your current is still too high for your glow controller so that can't be it.

At least removing plugs from the circuit does increase your glow time so that suggests your preheat system is wired correctly (with your glow plugs connected in parallel with each other and with this parallel combination then connected in series with the glow controller).

So I think this is more evidence that the glow controller you've been sold is not designed for a 12V cruiser with six 8.5V plugs. (It is more likely designed for a 24V cruiser with six 20.5V plugs and mislabelled in production by Toyota or whoever is making them.)

 

[bj40green]

You're missing nothing. It's not the relay, it's the controller. Your controller doesn't look good to me.
The wire size and the numbers of twists are not the same as your old (blown) controller. Jesper (in another thread) has the same problem, so I think that there is a part error on the Toyota side. Ordering again a new one won't solve the problem because you'll get the same wrong one.
My advice is to order the 28550-47040 controller. See my earlier posting #46

Rudi

Tom beat me with 5 minutes..... ...... just kidding

 

[athensrep]

Thank you guys. I appreciate the help as always.

I'll order the controller (28550-47040) and see how it goes. I'll probably play around with rewiring the old controller to see what I can figure out. I'll let you know how that goes as well.

What's with the controller lighting up when I'm cold cranking? That's never happened before.

 

[bj40green]

Here is the history from what I understand from your story.....
* The old controller never lightened up because you have the wrong glow plus (10.5V should be 8.5V plugs)
* While installing your "choke style" cut off cable you made a short and nuked the controller.
* The new controller is not the correct one. The part# is okay but the controller not. Production error.

From here you (and us) are running around in circles.
The new 28550-47040 should do the trick, but after installing you'll be back at square one..... it doesn't light up because of the wrong plugs.
When this works you can order the correct 8.5V plugs

Rudi

 

[lostmarbles]

.....What's with the controller lighting up when I'm cold cranking? That's never happened before.

Our wiring is such that preheat is activated again when our keys reach the start/crank position.

We don't usually notice this when looking at our glow controllers because for most of us they are properly matched to our glow plugs and therefore don't heat up as fast/easily as yours.

So with my controller, as soon as I start turning my key forwards/clockwise from the "glow" position (and through the "off" "ACC" and "on" positions) to the "start" position, my controller is fading in it's brightness. Then when my engine starts cranking (as a result of my key reaching the "start" position) my controller will simply stop fading.

I don't see it glow brighter again because:

• my controller is slower to brighten than it is to fade (and brightens only slowly anyway)
• my engine fires up easily so I have no need to leave my key in the "start" position for long, and
• my battery voltage falls substantially during cranking due the massive current-draw of my starter motor (thereby robbing power from my preheat heat system anyway).

 

[athensrep]

Thank you, gents, for bearing with me. I'm doing a few things. 8.5v plugs and correct-ish controller and I'm ordering a few feet of 15 gauge NiChrome wiring to redux the old controller (never hurts to have a spare or four).

 

[athensrep]

OK - so, I received the HJ47 enclosed glow plug controller along with the NGK 8.5V plugs. Hooked it all together and...the controller is glowing like a toaster oven in 3 seconds. Still. Crap.

I played with the old controller as well. I looped the 15 gauge five, six, and eight times. I still get the same thing - red hotness within 3 seconds.

Any ideas? Am I looking at rewiring? The old H will not start without a glow, so I should get something going. Any help is always appreciated.

 

[bj40green]

Sad to hear this. This leads me to the conclusion that there is a leak to ground in the wire between the controller and the busbar.

Disconnect the Black/Yellow stripe wire from the controller and from the busbar.

Run a new (test) wire (same AWG size) from the controller to the busbar. This should eliminate a wire problem.

Let us know how this turns out.

Rudi

 

[lostmarbles]

Well.. I'm completely baffled..

Is there anything at all touching your busbar other than the tops your six glow plugs and the thick BY wire at No.6 glow plug?

Maybe posting photos of your busbar area and of your glow relay may help us spot something?



Edit: I just went back through the thread and found that you've already posted these photos:

So I've just realised this HJ45 has the wrong ignition switch for "manual glow with glow controller preheat" and that you don't activate the preheat via your ignition switch (as you should) but instead you activate it via what would normally be "the afterglow button".

However I suspect that button/switch and it's wiring were not installed by Toyota but instead by a previous owner. And if so, who knows what they did there?

Here's another image for 1979 HJ45 preheat wiring:

If the factory had wired that afterglow switch, they would have run it from the engine fuse to the "g terminal" (where the WG wire coming from the glow position of the factory-correct ignition switch attaches) on your Glow Relay and it would be a "momentary-type switch". (In other words, it would automatically switch off whenever you remove your finger from it.)

How is yours set up there?

PS. I put a red dot on the "S terminal" because tests have shown that this terminal is usually a "dummy terminal" and actually connected to nothing at all within the relay.

 

[athensrep]

I'm not positive how they've wired up everything, but I'll take a closer look (as it ain't factory).

It's driving me mad as this is fairly simple set up. I'll grab some wire and run a test to the busbar. I've inspected the busbar - To me, it doesn't look factory either and the holes for the glow plugs look well worn, but nothing is touching it.

Off hand, anyone know the gauge wire to the busbar from the controller?

 

[bj40green]

On my BJ40 (4 cylinder) I used AWG10. Good for 55Amps.
I recommend AWG8 for your HJ (6 cylinder). Good for 73Amps.

Rudi

 

[athensrep]

Thanks Rudi.

I just got AWG8, unhooked black/yellow, and hooked it up to the busbar/controller.

Looks like a second is shaved off, but I'm still getting it heating up way too fast with no plugs glowing. I measured power coming into the controlled at around 12v and power to the busbar (at the controller connection AND the busbar connection) at a mere 0.7v.