Voltage Regulator and Brake Mastercylinder

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★ is in the wrong locale
Jul 2, 2003
Glen Waverley, Victoria, Australia
This past week I have returned to get an edumacation, an Advanced Diploma of Electronics and Communications Engineering. - So of course the irony gods strike me down.

I came out to the Hilux in the morning and the brakelights had been on all night. - I roll started and once on the freeway the chargelight comes on.

I suspect that there must of been a voltage spike when the engine got close to 3,000RPM in fifth gear to do 100km/h where as all gears are shifted up at 2,500RPM

Is there an updated version of 27700‑72030 which Toyota has not yet cross referenced back to the LN65? - It would of been right on 2 years old.
Fortunately I have a 30A fuse inline with the main wire from the 35A Alternator.

What is the difference between Brake Masters 47201‑35340 and 47201‑35450?
Is there an alternative that is `better` and bolts into and uses the low-level warning circuit?
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Is an aftermarket regulator a viable alternative to OEM?

What can be different with a regulator for cold conditions? - Would it still be beneficial in a non-cold environment?
27700-72030 Original; Replaced By 27700-63010, per toyotapartszone.com
27700-63010 Currently installed, Nippon Denso 026000-4052
27700-13090 Doesn't specify Hilux; Replaced By 27700-63010, per toyotapartszone.com
[strike]27700-64040 Hilux 08/1988-, per toyodiy.com[/strike] Infact, it is an internal regulator
27700-15060 Doesn't specify Hilux; Cold Spec, per toyodiy.com
27700-15061 Replaces 27700-15060, per quickparter.com
27700-63010 Replaces 27700-15061, per quickparter.com

Shalt an aftermarket Brake Master Cylinder be acceptable?
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On the regulator front, because I have already been using the latest iteration for the past two years I am going to see if the local Toyota Dealer can get either of the Cold spec 27700-15060 or 27700-15061, otherwise I'll go aftermarket.

Update: Neither Cold spec regulator exists in Australia.

Update: I've pulled the aftermarket trigger.
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The new regulator fixed the problem. - Chinks for the win :D

I've kept the 27700-63010 and I believe the original 27700-72030 is somewhere in my garage, both of which I want to test and see the differences.

This reminds myself that I have many used 15600-41010 Oil Filters and aftermarket versions sitting in my garage waiting to be cut open and compared. I have Valvoline made in China, Fleetguard made in USA, Ryco made in China, and 15600-41010 made in Australia. :doh:
The irony gods got me again.

On saturday when I started the engine to test if the regulator fixed my problem I noticed that the Glow Plug light did not illuminate and that the engine took awhile to start.

So now I'm reliant upon the now working charging system more than ever before until I can get and install a new Glow Plug Relay.
I don't even have time to diagnose the problem properly but throw parts at it and hope the problem is rectified. :wrench:

I forgot to give the good news. Whilst sitting in the Hilux at lunch time, the Hilux was recognised by a Teacher I had at a previous institution during the years 2011 and 2012, so we had a brief chat. :)
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The new Glowplug relay did not fix the problem because it was not broken. To not waste the AU$269 I re-purposed the old relay as the starter relay as I was never happy about the generic relay and connectors used when it was replaced by an autoelectrician.

I have been driving my parents FZJ80 for the past two weeks and with the downtime I got around to performing some diagnosis.
The two main wires in the loom in the vicinity of the glow plug lead are for the starter relay and the glow relay.
All of the glowplugs are shorted and all have less than 20 Ω of resistance.
Next I tested the resistance of the Glow system temperature sensor in the block and I got ~800 Ω whilst the engine was cooling down. :confused: I do not know what it should be.
Finally I guessed that the Preheating Timer is defective so I tried to get one from Toyota. Unfortunately Toyota 28521-54120/Nippon Denso 078400-0041 is no longer available.

At this stage I'm waiting for the Nippon Denso Glow Plugs to arrive at the Toyota Dealer along with new insulators and nuts.

Now I'm at a dead end.

Edit: I've tested at the connector for the preheat timer and I've found the pins that show the resistance of the temperature sensor. - I got 2,890k at the connector and directly at the sensor. [strike]Where I've written "~800 Ω" earlier, I could of remembered the wrong value as it could of been 8,000 Ω.[/strike] I'll add to the to-do list to measure the glow system resistor during warmup and operating temperature to see if the resistance increases with engine temperature.

I also want to identify the purpose of each of the preheat timer's conductors.
From the perspective of the loom:
|	One	Two	Skip	Three	Null	|
|	Five	Six	Seven	Eight	Null	|

Voltages listed are in order of key positions

One:	From Start Switch and 'Glow Plug Relay signal in'
Two:	To Regulator Terminal L:	0V, 6.07V, 14.02V
Skip:	Not Connected
Three:	From Ignition Switch and 'Main Relay power out':	0V, 12.04V, 14.14V
Four:	Not Connected
Five:	To Glow Resistor(Water Temperature Sensor)
Six:	From Glow Resistor(Water Temperature Sensor) and to ground
Seven:	To ground
Eight:	From Glow Indicator Light:	0V, 11.96V, 14.29V
Nine:	Not Connected

Update: I have measured the resistance of the glow resistor whilst the engine is running. - The resistance decreases as the temperature increases.
Today the values I got were:
Ambient Temperature: 2,730 Ω
Lower fat marking on gauge cluster: 800 Ω
Operating Temperature: 250 Ω

Update: The Pre-Heating Timer 28521-54120 is no longer available from Toyota and neither is its replacement 28521-54121 and neither is the part number 28521-54181 for the next iteration of Hilux.
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I have found out how to MacGyver the Glow Plugs. With the key at the second position and with a Paperclip between Pins 1 [To Glow Plug Relay] and 3 [From Ignition Switch] inside of the loom connector the Glow Plugs will heatup.

To prove that the Glow Indicator Light works, turn the key to the second position and with a Multimeter set to current and with its probes on pins 7 [Ground] and 8 [Glow Indicator Light cathode] the light in the gauge cluster will illuminate and the meter will read 0.22 Amperes.

The original Glow Plugs 19850-54031 correlate to:
NGK Y-118T1
Bosch GPT-215

There are 11 volt Glow Plugs with the same dimensions and are post-glow capable:
Toyota 19850-54090 [Which is paired with the 28521-54450 Preheating Timer in the LN67R-MDN]
NGK Y-715R
Bosch GPT-223

I bought the Bosch GPT-223 [subsequently found to be made in Japan] because they're cheaper than NGK and will allow for an aftermaket Pre-Heating Timer that has post-glow or a genuine Toyota Super Glow timer, and currently they work perfectly by MacGyver means.
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This afternoon I went to the Toyota dealer to get a Brake Master Cylinder and try another part number for a Preheating Timer.

At this time my conclusion is that Toyota does not make available any Preheating Timers for the second or third generation Hilux. My options at this point are to go to a junk and find a Nippon Denso Preheating Timer from a Daihatsu, Hino or Toyota from the same era as mine and then adapt it; the other options are to make one by copying the original, or wire up a momentary switch which also activates the indicator light.

The Brake Master Cylinder at AU$651.27 was significantly more expensive than I anticipated, where as the Taiwanese interpretation is sub $100 and in addition to the expense I have the pleasure of waiting 3-4 weeks for it arrive from Japan.
It is now school holidays and I've a few jobs to complete:
Transfercase front output shaft seal
Gearbox oil
Engine oil and filter - Can't do until I can find a 20 litre drum pump to buy
Glow plug switch - It's wired in but I need to file the dashboard hole wider because the momentary rocker won't return to centre.
Brake mastercylinder

I commenced the tasks to replace the brake mastercylinder.
I am using a giant syringe to remove the old brake fluid through each bleeder. I got to the rear left wheel where I noticed that the hardline is bent immediately behind where it threads into the wheelcylinder and obstructing access to this bleeder. - I've no idea what could have got into there, bend the hardline and be ejected.

[strike]I need help finding the part number for the hardline which goes from the T-piece along the left side of the rear axle housing, beneath the leafspring and to the wheelcylinder. - No joy with toyodiy[/strike]

Update: The hard brakeline is not available through Toyota. - Now I'll have to get a newy custom made. :bang:
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