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Discussion Starter · #1 ·
Little bit of background first:

I bought a running 4BD1T from the adapter guy (David of isuzudieselswapper) off eBay early this summer. I've spent the entire summer planting it (and a 700r4 + NP241) firmly within my 1972 Jeep Commando. It's bolted in and i'm to the point where I've started to hook things up, wire it, etc. - But i'm running into things that just confuse my young, inexperienced brain:

1. Can someone explain the power steering pump assembly to me? I see two steel lines coming out of the pump, no reservoir, and I can't ID which is high pressure or low pressure.

2. On the alternator, I've guessed that the largest gauge wire is output to battery, but what are the remaining wires (I've only had experience with GM, one-wire alternators...)?

3. I've got an autometer diesel tachometer that feeds off the alternator, any tips on how to calibrate it?

4. I understand that, much like a tractor, this engine has a fuel stop cable. I can pretty easily just use my old choke cable to manipulate that. What is this "fuel start cable" business, and how do I make use of it (If I even need to?)

That's all I can think of at the moment because I'm not actually staring wide-eyed at my engine compartment.

Any help would be great fellas,
 

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Little bit of background first:

I bought a running 4BD1T from the adapter guy (David of isuzudieselswapper) off eBay early this summer. I've spent the entire summer planting it (and a 700r4 + NP241) firmly within my 1972 Jeep Commando. It's bolted in and i'm to the point where I've started to hook things up, wire it, etc. - But i'm running into things that just confuse my young, inexperienced brain:

1. Can someone explain the power steering pump assembly to me? I see two steel lines coming out of the pump, no reservoir, and I can't ID which is high pressure or low pressure.

2. On the alternator, I've guessed that the largest gauge wire is output to battery, but what are the remaining wires (I've only had experience with GM, one-wire alternators...)?

3. I've got an autometer diesel tachometer that feeds off the alternator, any tips on how to calibrate it?

4. I understand that, much like a tractor, this engine has a fuel stop cable. I can pretty easily just use my old choke cable to manipulate that. What is this "fuel start cable" business, and how do I make use of it (If I even need to?)

That's all I can think of at the moment because I'm not actually staring wide-eyed at my engine compartment.

Any help would be great fellas,

Power steering pump.
Feed is on the bottom. Pressure out is on the front. You'll need to plumb it up to a reservoir and your steering box.

Alternator.
Mine has four wires, one is activation, this needs 12v supply before the alternator will produce any power.
One is for the charge light. On my truck I had to run this through a relay as you need to earth the charge light circuit to turn the light off. Lucas Electronics.:madflipoff:
Another is tach feed, this one is a 7V ripple.
Last one is a sense lead, it's feedback to regulate the charging voltage. It needs hooked up to your battery.

No idea about the gauge.

The trucks have a solenoid pack which pushes and pulls on the cables when provided power. There are two cables, one is fuel stop, the other is cold start enrichment. One wire to the ignition circuit controls the lot. The solenoid pack pulses the cold start cable one when you turn the key on.

We need pics.;)
 

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Discussion Starter · #3 ·
Well, ask and ye shall receive. This is the Jeep, I'm sure you all know what the engine looks like:




Unfortunately I don't have any recently-updated pictures, but the engine is installed, runs great, and all I've got left are a few peripherals until I'm driving around!

Now, as for more questions:

Does anyone happen to know the thread size/type for the oil sending unit hole? I want to use my oil pressure gauge (not a dummy light), but I can't for the life of me find a fitting that works.

The alternator looks similar to a GM alternator. I happen to have a shiny, one-wire, high-output GM alternator. Vacuum pump aside, any chance they are interchangeable?
 

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Very nice.

I notice your engine must be a much later model, it has two fan belts, mine only one and has the same turbo as the 4BD2T.

What did you do for drivetrain?
I see a 4wd front axle.

Remind me next week and I'll pull the oil pressure switch to measure the threads. It's on the floor in pieces so access is easy.:D
 

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Discussion Starter · #5 ·
I actually have no idea what year mine is. When I order parts I usually say it came out of an 89' chevy, gm, isuzu...
 

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Discussion Starter · #6 ·
Engine's been running for a week now, every time I crank it it's music to my ears!

Unfortunately I have no power steering, so I included a diagram so someone can confirm that I ID'd the lines correctly:

My current setup is:
#1 = high pressure to box
#2 = feed from reservoir

Now, I didn't bleed the lines or anything before installing them, i'm going to try that tomorrow. Could be my problem.

Let me know, and thanks for your help!
 
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