Dads 1971 FJ40 Swap

jtaco1

 
 
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Thanks guys. Hope to get on it again, but not this weekend. Wife went to Delaware to help a fiend that just had a baby, so I got the kids :D
 

jtaco1

 
 
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Didn't like how the radiator was packaging along with the fan, so sold the previous radiator setup and picked up a replacement 4 row aluminum radiator from Champion that bolts into the factory mount. Very nice looking radiator and should be more than adequate for this setup. Did a quick mockup and have 0.5" - 0.75" clearance between the radiator and clutch on the mechanical fan. Cleaned up the stock radiator mount, including removing broken hardware, re-tapped all bolt holes, and shot it with paint while the weather was nice this weekend. Hoping to mock up the fan shroud next and be ready to knock out the radiator hoses next.
 

jtaco1

 
 
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Took a break from working on the FJ40 - hard finding time with a 6 month old :biggrin:

Anyway, the radiator is finally in and done, had to lower it in the factory mount and move the mount over to the passenger side, as well as forward to clear the fan and center it. Overall I think it came out well.



Next up is making a mount for the computer and hooking the wiring harness up.
 

jtaco1

 
 
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Well I have been knocking things out on this project over the last few weeks. Only a few things left to do, which includes building the rear driveshaft, installing the transmission cooler and lines, putting hte seats back in, and filling all of the fluids. Here are a few pictures of the completed engine compartment.



Made a bracket that attaches to the inner fender to hold the ECU, fuse block, and fuel pump relay.

Here are the finished shifters, boots still need wrapped up.

And here is where the auxillary engine coolant temp and oil pressure guages got installed.
 
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shmukster

 
 
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Apr 20, 2003
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NE PA coal region
FJ40

JT- progress! Looks great, can hardly wait to see it and see how she runs! . I put my gauges in the same loaction as you and have a small tach on the dash above the light switch. Gary S
 

jtaco1

 
 
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Got some time today so we filled all of the fluids. Everything went as we planned and bled the steering. Went out to get more gas and came back to small puddle of coolant on the floor. Checked all of the hose and nothing. Coolant was dripping off the crank pulley, which confused me until I looked a little further up and noticed a hole in the bottom of the water pump that was slowly dripping. Shoved a golf tee in it to stop it and did some research since I had never seen it before. Turns out it is a weep hole that indicates when the water pump input shaft seal is going bad. Not sure if it was an issue before we bought the motor or if it developed from sitting the last few years.

Going to pick up a new water pump, but hold off on installing it until we fire it up to make sure there aren't other problems. Hope to fire it up tomorrow after the battery is done charging. Not looking forward to tearing the radiator out, but no room to pull the water pump otherwise. So close.
 

jtaco1

 
 
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Maybe I should update this :)

After finding out that the water pump was leaking, I picked a new one up and the project sat for the next 2 years while we completely redid our backyard with a pool and patio, kitchen renovation, and added pressures at work. Replaced the water pump and am now getting ready to complete the exhaust, but realized I never did anything with the original alternator harness in the truck.

I have three wires from the original alternator harness that need to go somewhere. I have a heavy gauge white with blue stripe wire, and two smaller wires that plugged into the back of the original alternator, white with a blue stripe and white with a black stripe. I am using the stock alternator that came on the 1998 Chevy 4.3.

I have searched around on here, reviewed wiring diagrams, and looked at other sites, but haven't found a clear answer on how to run the original wires so everything functions as it should. Would hate to turn the key and nothing on the truck works, other than the motor since it is stand alone, or it goes up in smoke from an electrical fire. Any pointers are appreciated or if you want to stop by and check things out, cold beer is waiting.
 
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I have three wires from the original alternator harness that need to go somewhere. I have a heavy gauge white with blue stripe wire, and two smaller wires that plugged into the back of the original alternator, white with a blue stripe and white with a black stripe. I am using the stock alternator that came on the 1998 Chevy 4.3.

I have searched around on here, reviewed wiring diagrams, and looked at other sites, but haven't found a clear answer on how to run the original wires so everything functions as it should. Would hate to turn the key and nothing on the truck works, other than the motor since it is stand alone, or it goes up in smoke from an electrical fire. Any pointers are appreciated or if you want to stop by and check things out, cold beer is waiting.
I'll poke around some wiring diagrams tomorrow at work. The two smaller wires should be an exiter wire and another wire for the idiot light/gauge but I'll confirm that tomorrow. Could make a house call if need be. I tend to end up in some wiring nightmares at work:

IMG_7963.JPG
 

jtaco1

 
 
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Awesome, thanks for taking a look. The way my engine harness is setup, there is wire that goes through a dummy light that plugs into the 4-prong connector on the side of the alternator, only one wire location is used. Only other hookup at the alternator is the power cable to the stud on the back from the power lug that I installed.

Simple wiring I can handle, but the integration of new into the old leaves me scratching my head. That pile of wiring gives me anxiety just looking at it. Thanks again.
 
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So the big wire on the gm alternator should run to to the battery. That's probably obvious, but just to keep any confusion out. From there I assume there is some sort of fat cable that runs to the fuse block/power distrobution.

From what I looked up this morning the 4.3 uses a classic gm single wire set up. This will need a 12v switched signal to turn the alternator on. This is usually done via the idiot light wire. Just check for a 12v signal when the key is on and that should be good. If you need to know what wire on the fj side I'll need to see a diagram for that. Our manuals at work don't go back that far. Worst case I make the trip out, it will give me an excuse to hit up Quaker steak and lube.
 

jtaco1

 
 
Joined
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I have the battery setup a little different than what was original. From the positive post a feed cable goes to a terminal post, which then has a feed cable going to the lug on the back of the alternator and another feed cable going to the starter. We use the terminal post as the disconnect for storage. The thicker white with blue stripe wire used to go to the battery, but should no longer be needed based upon how the new power feed cables are run.

I have a 12v switched source coming from the ignition switch to a dummy light and then to the one wire on the alternator plug. So with that setup, I should be good for the engine running and the alternator to charge.

The issue I think I will have is that the fuse block in the truck will not have power since those two smaller white wires with blue and black stripes are no longer connected to a power source. The 1971 wiring diagram I reviewed showed them getting their power from the alternator and powering the top and bottom portion of the fuse block after going through the voltage regulator. Below is a copy of the wiring diagram.

I am wondering if I could just put ring terminals on the two smaller wires and hook them to the stud on the back of the alternator, or if there is somewhere else they should be hooked into to power the rest of the truck. The motor and fuel pump are completely stand alone from the wiring system of the truck and not integrated other than the power hook up at the ignition switch.

IMG_0407.JPG
 
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Going off of the above diagram it looks like the two smaller wires (wg and wb) are for the external voltage regulator and no longer needed. The one needed to feed the accessories that are not engine related would be the big wire marked "wl". This will be a constant 12v feed. You could indeed put a ring terminal on the back of the alternator, on the battery, or even a junction block after the battery if your vehicle is so equipped. Personally I'd put it in whatever location is the cleanest looking.
 

jtaco1

 
 
Joined
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Was doing some work on some other vehicles and decided to give firing this up a shot after building the exhaust today. Thought maybe have it ready for the meeting in a few weeks.

Good news:
It turns over when you turn the key!!
We have fuel too (only a few fittings needed an extra turn or two).

Bad news:
It doesn’t fire off and there is some more wiring that needs figured out since the rest of the Cruiser is dead when the power is on :(

Spark is there, but appears weak, going to troubleshoot and replace a few parts and see what that gets us. Then figure out what else I need to do to get power back to the fuse block so the rest of the Cruiser can come to life.
 
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