Builds Isuzu 4HE1TC into FJ62 (2 Viewers)

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I hadn't even considered that the AW450 ecu could be compatible with the A442. THAT would be toooo simple. Post up the pictures and I'll check it out. What does the AW450 use for speed and throttle position?

To detect speed, the AW450 TCM uses two sensors: The primary sensor is located where the speedometer gear goes and IIRC, it generates a series of pulses that are used by the TCM and to drive the speedometer. The secondary (backup) sensor is a magnetic sensor that is adjacent to the park gear and detects the teeth as they pass by.

The throttle position sensor is a rheostat located at the accelerator pedal. There is also a kick down switch also located at the accelaerator pedal that closes when the accelerator is fully depressed.
 
I hadn't even considered that the AW450 ecu could be compatible with the A442. THAT would be toooo simple. Post up the pictures and I'll check it out. What does the AW450 use for speed and throttle position?

Here are the photos of the AW450 TCM. Like the transmission, it is made by Aisin. Let us know how it compares to yours.
TCM.webp
TCM-Connector.webp
 
is the truck you got the motor and trans out of 12v? almost all of the isuzus over here are 24v, like 95%. a couple of the lightweight models (NKR) in previous years were 12v, but not anymore.
 
is the truck you got the motor and trans out of 12v? almost all of the isuzus over here are 24v, like 95%. a couple of the lightweight models (NKR) in previous years were 12v, but not anymore.

All the US NPR's are 12 volt as are the NQRs also.
 
lucky buggers. if we wanted to do that with one of our motors it would be painful, unless you had a 24v cruiser

NO, Mate, you southern hemisphere residents are the lucky buggers that can buy a 60 or 80 series with a quality diesel already installed by toyota. Let's not even discuss the fact that you can get the 70 series....:flipoff2:

Back to the topic, sorry ASTR, my weekend and week have gone to hell at work, I'll try to snap some pics later this week.
 
I was doing some reading and wondering about how the 4HE1TC shuts down? In the parts list I saw that there was a "Shutdown Motor" which I'm assuming moves a mechanical linkage that blocks fuel flow in the injection pump when activated? I had no idea about diesel motors being able to "run away" from you if you had a fully mechanical fuel system, so wondering how these motors were shut down.

That being said, how is the fuel system set up on the Isuzu NPR? I'm assuming a small lift pump in the tank and then the IP does the rest?

-Phil
 
I pulled my TCM out tonight far enough to see they are quite different in plug configuration, etc. My son has my camera, so no pics. I imagine the AW450 TCM controls more stuff inside, making it run the A442 might be difficult. Since my TCM is labeled 1FZ-FE I wonder if there aren't some in OZ or canada that say 1HDT or some thing groovy like that that would plug into my harness without too much rewiring for throttle position, etc.
 
I was doing some reading and wondering about how the 4HE1TC shuts down? In the parts list I saw that there was a "Shutdown Motor" which I'm assuming moves a mechanical linkage that blocks fuel flow in the injection pump when activated? I had no idea about diesel motors being able to "run away" from you if you had a fully mechanical fuel system, so wondering how these motors were shut down.

That being said, how is the fuel system set up on the Isuzu NPR? I'm assuming a small lift pump in the tank and then the IP does the rest?

-Phil

The IP setup on the 4HE1TC is very conventional . There is a lever on the IP that is connected by a cable to a shutdown motor. When you turn off the ignition key, the motor is activated and moves the cable. What happens inside the IP, I don't know but I'm sure someone else here can tell you. The innards of an IP are a mystery to me.

There is no lift pump in the Isuzu tank. There is a standard lift pump on the IP that sucks fuel from the tank. There is also a manual pump as part of the lift pump used to purge the air out of the system.
 
There is no lift pump in the Isuzu tank. There is a standard lift pump on the IP that sucks fuel from the tank. There is also a manual pump as part of the lift pump used to purge the air out of the system.

Is there a lift pump on our LC's that we will need to remove?

The auto purge feature is nice - should negate the need to manually bleed the system, no?

-Phil
 
Is there a lift pump on our LC's that we will need to remove?

If your truck is carburated then you will not have an in-tank pump. If it is injected, you will have one that you will have to deal with.

The auto purge feature is nice - should negate the need to manually bleed the system, no?

-Phil

There is no auto purge, just a manual pump like most other diesels.
 
Spacer Solution

I made a little progress last night. I took some measurements with the A440F output shaft installed both in the A440F case and the AW450 case and determined that I need a spacer 0.484” thick between the AW450 case and the T-case adapter to position both the T-case input gear and the park gear correctly. I made up some test spacer blocks to verify. The first photo shows the front half of the split case mounted to the T-case adapter, mounted to the AW450 case with the spacer blocks installed. Everything lines up correctly and the interference problem between the park gear and the T-case adapter is resolved.

To make the actual spacer, I was going to machine it from a ½” aluminum plate, however, this would require a lot of work to get the shape right and to locate and drill all of holes accurately. A better idea is to slice off the front section of the original AW450 tail housing and mill it to the right thickness. It already has the correct shape and all of the holes in the correct locations. So I’ll give this a try (2nd photo)
Spacer-test.webp
Spacer-cut.webp
 
I pulled my TCM out tonight far enough to see they are quite different in plug configuration, etc. My son has my camera, so no pics. I imagine the AW450 TCM controls more stuff inside, making it run the A442 might be difficult. Since my TCM is labeled 1FZ-FE I wonder if there aren't some in OZ or canada that say 1HDT or some thing groovy like that that would plug into my harness without too much rewiring for throttle position, etc.

Too bad but I suppose it was too much to hope for. I did briefly look through the A442F FSM and it appears that the A442F is a transition between the A440F and the AW450. It uses solenoids under TCM control, to do the shifting like the AW450 but uses a throtle valve cable that connects between the transmission and the throttle body like the A440F to obtain throttle position information.

Just out of curiousity, did the TCM have a Toyota or Aisin label on it?
 
Just out of curiousity, did the TCM have a Toyota or Aisin label on it?

In my HDJ80 that come factory with the A442F there are to " boxes " the ETC and the tranny control relay .. both Aisin labeled ..
 
As I recall my TCM had both Aisin and Toyota markings on it, not sure as that was two nights ago, and I didn't get a picture . Mine also has a tranny control relay and a TCM. Tapage, does your 442 also have a throttle cable? I think this might be a pretty easy swap if the cable controls shift points. I think swapping TCM's might not be necessary if the only input from the engine is the throttle cable. At this point, I'm holding my breath to see how the starter issue plays out.
 
...A better idea is to slice off the front section of the original AW450 tail housing and mill it to the right thickness. It already has the correct shape and all of the holes in the correct locations. So I’ll give this a try (2nd photo)

If you've got acces to CNC shop services then you could simply scan the facing surface of tailhousing, convert image into .dxf or another CAD format and ask the shop to replicate this shape in aluminium or steel plate in desired thickness.

Readng this thread is pure pleasure :clap:
 
If you've got acces to CNC shop services then you could simply scan the facing surface of tailhousing, convert image into .dxf or another CAD format and ask the shop to replicate this shape in aluminium or steel plate in desired thickness.

Readng this thread is pure pleasure :clap:

Thanks for the comp. Its been a fun project.

I originally had similar thoughts regarding how to make the spacer, but instead of scanning the tailhousing, I was going to scan the tailhousing gasket. It fits in a flatbed scanner much better ;)

I have an old CNC mill that I'm trying to get back into operation. I've done some basic stuff with it but I still having some problems with the software that converts .dxf to G-code. In the interest of keeping this project moving, I decided it would be quicker to make the spacer by slicing off a section of the old AW450 tailhousing and then surface milling it to the right thickness. This I think I can do myself on my mill. Besides, I have no other use for the old tailhousing.

Also, if my plan fails, I'll consider your approach as Plan B!

Maybe this weekend, I'll fire up the ole chainsaw and try slicing off a section. I just need to find a volunteer to hold the tailhousing while I operate the saw!
 
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Make sure you keep measurements/files of these spacers you build because others who follow in your shadow might want to buy either the part itself or the plan from you :)
 
Make sure you keep measurements/files of these spacers you build because others who follow in your shadow might want to buy either the part itself or the plan from you :)

I haven't posted the exact measurements because they may still require tweeking. Once they are final, I'll post them.
 

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