Rebuild 74 FJ40 RHD from Down Under - 2F to 2H to 12HT - 40 series Axles with 80 series Coils

[watrob]

With help of Rudi (bj40green) whom I wish to thank, solved my problem with the Fuel Control Relay that works with an Edic motor, converting it to work with a VSV on a 12HT. The following is a guide to achieving this, and the input from Rudi.

Hi Rudi,

I am running a HJ47 1983 model super glow wiring loom. I have shorted using the current wires with 2 12ht glow plug relays and the 12ht Pre Heat Timer.

I have installed the low pressure oil switch into the 12HT engine so every thing will work with the HJ47 FCR except of coarse the 4 wires going to the FCM (edic) is not on a 12HT engine.

I am trying to understand these 4 wires. "M" acts as power circuit but terminates to earth if the low oil pressure switch does open within so many seconds. I thought I read some where that connecting "M" to the VSV and a earth wire, combining the (joining) the "Y" & "R" together you can create power running onto the VSV on turning the ignition to "ON".

I believe "B" supplies power to the FCR via a FL from the battery all the time whether the ignition is turned on or not.

I am trying to incorporate the low pressure oil sensor into the system as protection which should the oil pressure not come up stops the 12volt feed to the VSV.

Your electrical wizardry skills would be greatfully appreciated.

(Rudi said)

"M" has nothing to do with the OPS. When the power stops to the coil of the bottom right relay, the relay falls back to the rest position causing a short over the EDIC motor. This is done to let the motor stop immediately ( same principle as the wiper motor). In other words there is no run out or after run on the motor.
Connect OI and D together to one terminal on the VSV and ground to the other and it should work.
BUT........ when the center relay (in the diagram) falls back from "OI (start)" to "D (run)" (the left relay is in the D position) there will be a fraction of a second no power to the VSV. Try it.
That round thing with 4 wires is the position sensor and stops the power to the motor when a position is reached.

Rudi

 

[watrob]

Hi Rudi, thanks for that, so "OI & D" gives me power to the VSV when the ignition is turn to ON & START :-

So when the ignition is ON, power is on the "Left Relay" which in turn moves the "Middle Relay" into "D" (RUN) position, when the ignition key is turned to START the "Left Relay" changes to the OI position (START overject), when the key is released back to ON the "Left Relay" sends power back to the "Middle Relay" which in turn moves to the "D" position.
What I don't understand is when the key is in "ACC" (OFF) power is still always on "+B" from the FL of the battery, can you explain to me what's cutting the 12 volt power supply off internally in relationship to the "Right Relay" where "B" & "M" are concerned.?

(Rudi said)

This is typical Toyota way of drawing a relay. I consider the coil the relay no matter where the contacts are.
So.... the left coil is the RED contacts.
The middle relay is the GREEN contacts.
The right relay are the BLUE contacts.
The diagram is in the "OFF" position. In other words; the relays are powerless and at rest position.
When the Starter Switch is in the IG (run) position, the transistor on the right is conducting and thus activating the left relay (red) which will move to the D position.
When the Starter Switch is moved to the Start position, the middle relay (green) is activated and moves the contacts to the OI position. At this point D is powerless!
When you release the key after cranking (back to IG or run position) and D is activated again. So D is powerless during cranking.
Can you still follow this?????????

if you don't understand electronics, transistors, capacitors, resistors, diodes and so on it's very difficult to explain.
Believe me, that OPS sends a signal to the transistor on the left which is delayed by the left capacitor to finally shut off the relay on the right.

Rudi

 

[watrob]

(Rudi said)

Here is your diagram with an explanation in color. I used different colors because in my world Red is always +12V.
So RED is battery voltage that goes through the M relay and stops at the ST relay.
When the key is off, the voltage stops on the S terminal which you don't use.
Key in the IG (run) position = power (blue line) to the transistor circuit (including the OPS) and the D terminal is 12V (for your VSV).
Key in the ST (start) position = power (green line) to the middle relay which switches from D to OI terminal (for your VSV).
So now you have +12V intermittent on the D and OI terminals. But there is a minor problem.
The M relay is in series and your VSV is not going to like that. So.... take out the M relay and jump the coil contacts (red dotted line).
As I said before... when the middle relay flips from D to OI there is a split second no power to your VSV.
I don't know if that is a problem. I think not but you never know.

Rudi

 

[watrob]

Hi Rudi, had a terrible day to day, a person if you can call him that broke into my offices last night and in 6 minutes kicked 4 doors in and smashed 3 plaster walls. Caught it on security video but was gone before security showed up, nothing stolen, probably just looking for petty cash.

Thank's for outlining the circuit, its very much appreciated, in regards to this statement:-

"The M relay is in series and your VSV is not going to like that. So.... take out the M relay and jump the coil contacts (red dotted line)."

1. Can I take out the M Relay out of circuit by simply cutting & jumping the coil contacts?

2. I have to completely remove this M relay off the circuit board is what you mean by "take out" or

3. You were just configurably speaking "take out of circuit" by cutting the coil wire contacts and jumping these two pins. See below photo.

I am sorry for being so pedantic but I am hoping that others that see this thread that do these 2H or 3B Super Glow Systems etc conversions to 12HT's engines whether in 40 series or 60 series have a guide to follow. Thanks for your patience.

I soldered a jumper wire across the coil.

 

[watrob]

(Rudi said)

You can remove the relay and jump the coil contacts or just put a jumper in (as in the lower picture) and leave the relay where it is.
You may but don't have to cut the 2 coil wires.

(Rudi said)

Anyway.... let's get this unit working and if it turns out to be a problem we can figure something out.

 

[watrob]

Thanks Rudi, you know how we have been discussing there maybe a slight delay for a second or two of 12volts when the relays flip back from OI to D,
what your thoughts on placing a Electrolytic Capacitor say 15volts 25mfd across the bobbin (coil) of relay ST (OI)?

(Rudi said)

I don't know where you get those 2 seconds. I didn't mention it as far as I know.

An Elec. Cap. is not going to do it. It will delay the fall back. I'm thinking about a diode that keeps the voltage to the VSV while the relay falls back. While typing this I have another idea but have to work it out.

Rudi

 

[watrob]

Hi Rudi, 1-2 second thing is just a matter of speech, I was just thinking that this split second of power loss to the VSV which activates the vacuum switch which inturn activates the actuator on the butterfly in the inlet manifold it's attached too could at this point become a 1-2 second engine splutter as the butterfly turns, but one could also say that the reaction time of the mechanical vacuum part of the switch & the mechanical actuator will be much to slow to react to a pulse of lost 12 volt power to the switch?
Even the 2h has a slight splutter when the edic motor goes from OI to D because the Oil Pressure cut off switch kicks in all at the same time, so I don't think it may be a problem, I still have the oil pressure switch in circuit which is probably going to do the same thing and momentarily cut the 12 volt supply to the VSV anyway if oil pressure is a little slow to come up to pressure as with the 2H.
The diode thing is a thought as you say, I will make the mods to the FCR as outlined, they will be easy enough to check with a multimeter when I turn the ignition to ON & then to START, it will show the delay of the 12 volt switch from OI to D as well.

(Rudi said)

While you have the voltmeter out..... check if there is voltage on IG when you turn the key to ST(art).
If so..... i have a solution to skip that split second "no voltage to the VSV" problem.

Rudi

 

[watrob]

Will do Rudi, but I won't be able to do it until the weekend as the 40 is up at the beach house.

 

[watrob]

I ordered a selection of fusible link wire as it is becoming hard to get hold of here?

 

[watrob]

Have finished the steering shafts, spline has been added to steering column shaft of the 40 series to which a bearing has been added to the bottom end of the column housing. I have added half of a 75 series uni joint combined to the half of a 80 series uni joint with the attached rag joint. I am then using a intermediate collapsible 80 series steering shaft with a uni joint which slips straight onto the 60 series power steering box.

The length adjustment is on the 40 series column shaft which is splined, I know its to long so I can simply cut down the length as required.

There has been no welding involved so the harden steel shafts have not been compromised and does not need to be re-hardened, it also gives me the added benefit of having a collapsible steering shaft for safety.

PS. I also have a small amount of adjustment on the uni (top & bottom) of the 80 series shaft where it connects onto the 60 series power steering box.

 

[wongtsenhin]

Love your tidy and neat work.

 

[Bambi Girl]

Hi watrob
First of all nice work.
Enjoy reading your build.
Fusible link wire.
Were do I go shopping to find ?
I will be needing some over the next month or two.
I'm Brisbane based
Cheers



...via IH8MUD app

 

[watrob]

Hi watrob
First of all nice work.
Enjoy reading your build.
Fusible link wire.
Were do I go shopping to find ?
I will be needing some over the next month or two.
I'm Brisbane based
Cheers



...via IH8MUD app

I bought two lots, one lot from ebay US and the other from a dealer in Sydney http://www.larpro.com.au/larpro/category/176, his wire is rated as low as 40amps, which in the old method is around 13 amps continuous rating. You have to consider the AWG & the Gauge of the wire, not the colour code because green for a Ford might be Orange for Toyota, there is not standard in the colours.

(see below) The larger the Gauge the lower the amp protection, also a 14 gauge FL will protect a 10 gauge wire circuit, the 14 gauge will burn out before a 10 gauge, it can get confusing. Also protection goes sq mm numbers, so you might see on a circuit 0.5g, which is 0.5sq mm (mm2) green, but be carefully of the colour, go on the 0.5sq mm.

This photo above shows 0.5 as grey, whereas Toyota is green, same as Nissan. And also remember the length as this sets the resistance level, so always replace a 6" long FL with the same length.

So go by the mm2 rating and not the colour.

 

[watrob]

Went shopping today for odds & ends for my 40 (a few spares) and what do I end up buying is another 12HT engine, this one has a reco IP & turbo waiting to be installed. The head has been reco'd as well and installed, comes with alternator, clutch, plus electrics, 1989 model, sitting on pallet. Needs a bottom end rebuild as it still blowed smoke after all these other items had been reco'd, so the owner started to strip it down again but has had enough, couldn't help myself.

Bantered for a bit and settled on $1,400, I figured the bottom end will cost around $1,500 to $2,000, all up around $3,500 for a fully rebuilt 12ht is not bad?

That's about a 3rd of the price of my last 12Ht rebuild.

 

[Bambi Girl]

Hi
Thank you for the fusible link info.
Cheers


...via IH8MUD app

 

[watrob]

I have now started work on my HJ/BJ tacho. (standard image)

With the 12HT diesel engine which is in the 62 series, the instrument cluster has a Red & Green turbo warning lights in the tacho.

These two lights are attached to these two vacuum switches, usually bolted on the right hand side guard next to the air filter.

So I bought a couple Green & Red 12v led's to install into my 40 series tacho, which I will connect to these two switches.

And will position them like this.

 

[watrob]

Radiator hoses arrived today,

 

[watrob]

Picking up my front & rear brake lines this afternoon and with a bit of luck should be able to fire up the engine late Sunday if all goes well. Also made a heavy duty alloy battery tray and pickup a new low maintenance battery, nearly done, looks like a big weekend coming up.

 

[watrob]

I pulled apart my tacho over the weekend and install the turbo red & green led's, cam up pretty good.

 

[watrob]

Also re-wired the Pre Heat Timer plug on the HJ47 wiring loom by installing the larger plug that is required for the 12HT Pre Heat Timer. I then used a multimeter to check the wires went back to the correct corresponding connections.