Builds 1987 fj60 12h-t h55f conversion (5 Viewers)

[roma042987]

I cant praise these stainless trays enough they are awesome! Passenger side tray installed.

I sprayed the A pipe welds and flanges with some cold galvanizing compound for corrosion protection. Only made another two foot section of the exhaust last night so not much to show there. Im going to go ahead and driver it in to where I work and do some more exhaust fitting with it on a lift and also need to run my bends over to the local muffler shop so they can swell them all on one end.

I fired it up last night and it immediately shut off. SO I check the shutter diaphragm and sure enough its closed! The shutter vsv is open in its normal state (at rest) It needs 12v applied to close and the shutter to remain open for the engine to run. Which is much simpler than what I had initially thought that it needed 12v to shut the engine down. So all be pulling that rocker switch of the dash or at least repurposing it and simply make a 2 foot long harness to run from the shutter vsv to an existing ignition on 12v plug on the driver fender that used to run to the carb. Easy peazy!

Oh and my denso compressor arrived today so i'll be putting it on this evening and driving it home. Need to get one more fitting fixed on my hoses and I can charge the a/c up.

 

[roma042987]

Holy crap, nice work. My question is, where do you find the time to put in your cruiser?

Thanks! Heck you have no idea I work about 11 hours a day and every other Saturday so I actually have very little time to work on it. It's usually just a few hours a week. There is so much I would love to do to it if a had some more free time. I really need to go through the front axle which is actually the next project. If I had the space id go ahead and pull the body off the frame and powder coat the frame and redo the suspension and coat the underside of the body. Im actually doing all of this in my friends garage (Tucker 75fj40 restore) I only have a carport at my house. All of my tools and compressor etc I took to his place when we started his project a couple of years ago.

 

[mongoose2231]

i see you have a new compressor. can you please show a picture of where its supposed to be wired. mine was manually wired to a switch and i cannot for the love of god find the end where the black and white cloth wire is supposed to connect to. Someone mentioned it goes into the alternator harness but i cannot find a loose end. I have a 2h diesel, which i assume is wired just like your 12ht. Thanks. and great work!

 

[roma042987]

i see you have a new compressor. can you please show a picture of where its supposed to be wired. mine was manually wired to a switch and i cannot for the love of god find the end where the black and white cloth wire is supposed to connect to. Someone mentioned it goes into the alternator harness but i cannot find a loose end. I have a 2h diesel, which i assume is wired just like your 12ht. Thanks. and great work!

since my cruiser originally had a 2f I had to extend the alternator and a/c wires to reach to the driver side of the engine bay so its not exactly original as an hj61 or hj60 would be. However you should just have a wire in your alternator harness loom for the a/c compressor coil.

 

[hsumbal]

Thanks! Heck you have no idea I work about 11 hours a day and every other Saturday so I actually have very little time to work on it. It's usually just a few hours a week. There is so much I would love to do to it if a had some more free time. I really need to go through the front axle which is actually the next project. If I had the space id go ahead and pull the body off the frame and powder coat the frame and redo the suspension and coat the underside of the body. Im actually doing all of this in my friends garage (Tucker 75fj40 restore) I only have a carport at my house. All of my tools and compressor etc I took to his place when we started his project a couple of years ago.

Very good progress keeping in mind your schedule....

 

[roma042987]

Very good progress keeping in mind your schedule....

Thanks!

 

[roma042987]

ok so I drove the truck home from Tuckers Thursday evening however the alternator is not charging. The 12ht alternator is a three wire connector. 12volt battery, 12volt ignition, and charge light. The fj60 harness is only two wire however it has 12v battery and 12v ignition. so I left the charge light pin on the alternator empty. I believe the charge light circuit uses a different input elsewhere on the fj60. My understanding is that the alternator should be charging with 12v at those two terminals but its not. I know its possible that a brand new alternator can be bad out of the box but what are the chances of that?. Another theory I have is maybe since I powder coated the alternator brackets it has lost its ground and I need to add a ground strap to it?

 

[hsumbal]

ok so I drove the truck home from Tuckers Thursday evening however the alternator is not charging. The 12ht alternator is a three wire connector. 12volt battery, 12volt ignition, and charge light. The fj60 harness is only two wire however it has 12v battery and 12v ignition. so I left the charge light pin on the alternator empty. I believe the charge light circuit uses a different input elsewhere on the fj60. My understanding is that the alternator should be charging with 12v at those two terminals but its not. I know its possible that a brand new alternator can be bad out of the box but what are the chances of that?. Another theory I have is maybe since I powder coated the alternator brackets it has lost its ground and I need to add a ground strap to it?

Nice to know that its on road

If you can find some time post a video of the 12Ht running

Thanks

 

[roma042987]

Nice to know that its on road

If you can find some time post a video of the 12Ht running

Thanks

I sure will! I actually have a pretty neat video of the engine running when I started it in the trailer that is pretty neat. Although I don't know how to post video so would need to get someone to show me.

I must say I've heard quiet a bit of hype about the 12ht and even knowing that going in im still very impressed! It feels like a rocket ship to me. Im not sure if that dump pipe made all the difference or what but it drives unlike any other cruiser I've driven (I also have a 99 uzj100). My truck still has the 3.70s and the gearing seems to be perfect right now. I am running a 31x10.50 so im not sure what 33s would feel like. The 12ht makes quick work of the h55f and im in 5th gear on stretches where the 2f would be lugging around in 3rd or 4th.

Im going to work out the alternator today hopefully and charge up the a/c system. Also still need to wire and install the hj60 tach and finish up the exhaust.

 

[DanS HJ-45]

I must say I've heard quiet a bit of hype about the 12ht and even knowing that going in im still very impressed! It feels like a rocket ship to me.

Indeed it does! Ours still feels like a sports car (as much as a 60 can) every time I drive it.

Bummer about the alternator, I just swapped the alternator wiring from the half-cut onto the left side FJ-60 harness, and removed the stock wiring from the right side harness.

If all else fails, is there are alternator shop near you? Those guys don't need diagrams, they can typically figure out how to make it work with a very quick look.

Dan

 

[roma042987]

Bummer about the alternator, I just swapped the alternator wiring from the half-cut onto the left side FJ-60 harness, and removed the stock wiring from the right side harness.

If all else fails, is there are alternator shop near you? Those guys don't need diagrams, they can typically figure out how to make it work with a very quick look.

Dan

Yeah there is one close by. I actually have a spare I'm going get tested first. I'm pretty certain I have it wired correctly now with all three wires connected but it's still not charging. On top of that the charge light is not illuminating either. I started checking fuses and when I put a test light across the charge fuse the charge indicator illuminates. Also the ac wire for the compressor isn't getting power either. It worked fine with the 2f. I'm really think I got a bad fuse somewhere with ac issue

 

[roma042987]

Two theories I've come up with dwelling on my ac this evening. First..I flushed the evaporator with flush solvent and an ac gun possibly damaged the ac pressure switch. Or second I've read some unreliable info that the ac amplifier looks for rpm signal which its not seeing since the diesel tach isn't installed and the gasser tach is sitting at 0. I did hot wire the compressor after charging it today to check pressures and it does blow ice cold it's just not getting the needed 12v signal.

 

[hsumbal]

I sure will! I actually have a pretty neat video of the engine running when I started it in the trailer that is pretty neat. Although I don't know how to post video so would need to get someone to show me.

I must say I've heard quiet a bit of hype about the 12ht and even knowing that going in im still very impressed! It feels like a rocket ship to me. Im not sure if that dump pipe made all the difference or what but it drives unlike any other cruiser I've driven (I also have a 99 uzj100). My truck still has the 3.70s and the gearing seems to be perfect right now. I am running a 31x10.50 so im not sure what 33s would feel like. The 12ht makes quick work of the h55f and im in 5th gear on stretches where the 2f would be lugging around in 3rd or 4th.

Im going to work out the alternator today hopefully and charge up the a/c system. Also still need to wire and install the hj60 tach and finish up the exhaust.

I also love the torque which these old school diesels deliver at low RPM. I run the same setup with my 1HZ, 31s and 3.70....and I think this tire size is not ideal...

235/85R16 will make your vehicle much nicer to drive.

 

[DanS HJ-45]

Two theories I've come up with dwelling on my ac this evening. First..I flushed the evaporator with flush solvent and an ac gun possibly damaged the ac pressure switch. Or second I've read some unreliable info that the ac amplifier looks for rpm signal which its not seeing since the diesel tach isn't installed and the gasser tach is sitting at 0. I did hot wire the compressor after charging it today to check pressures and it does blow ice cold it's just not getting the needed 12v signal.

The gas AC amplifier takes a couple inputs to allow the AC compressor to engage. (off the top of my head

• RPM
• AC Switch
• AC Pressure Switch
• Blower Motor
• Coolant Temp(?)

The stock HJ-61 AC Amplifier uses the same inputs, EXCEPT the RPM, and gets a signal from the start circuitry. The reason that the Gas AC Amplifier inhibits the AC at low rpm is to unload the engine for starting, or if you are really lugging the engine, and about to stall it. The diesel accomplishes the same thing by inhibiting the AC compressor when the starter is engaged, but has no minimum RPM, likely because the diesel has so much torque that the AC compressor just doesn't effect it as much as the 2F.

There is a jumper you can install that will trick the AC amplifier into thinking you have adequate RPM at all times, but I'm not positive off the top of my head what it is (we used the AC amplifier from the HJ-61).

Dan

 

[roma042987]

Cool that helps. I spent couple of hours reading up on the subject last night and that's about what I gathered as well. Looks like you can jump a yellow and black white wire at the amp and that bypasses the entire amp circuit. I would like to keep the low pressure and thermoswitch function of the amp. It looks like someone was working on decoding the 60 amp to just bypass the rpm input but that thread hasn't been updated since april. Also apparently some use a 62 amp because it uses an ecu input, using the 62 amp would I still need to mimic the ecu input or no?

The gas AC amplifier takes a couple inputs to allow the AC compressor to engage. (off the top of my head

• RPM
• AC Switch
• AC Pressure Switch
• Blower Motor
• Coolant Temp(?)

The stock HJ-61 AC Amplifier uses the same inputs, EXCEPT the RPM, and gets a signal from the start circuitry. The reason that the Gas AC Amplifier inhibits the AC at low rpm is to unload the engine for starting, or if you are really lugging the engine, and about to stall it. The diesel accomplishes the same thing by inhibiting the AC compressor when the starter is engaged, but has no minimum RPM, likely because the diesel has so much torque that the AC compressor just doesn't effect it as much as the 2F.

There is a jumper you can install that will trick the AC amplifier into thinking you have adequate RPM at all times, but I'm not positive off the top of my head what it is (we used the AC amplifier from the HJ-61).

Dan

 

[roma042987]

Ac works thanks to this thread this HTML class. Value is https://forum.ih8mud.
I rode over to Elbert's this morning to borrow an fsm and took a couple of pictures of the rigs together i cut this resistor in the amp and ac works perfect now.

 

[roma042987]

New compressor with the two custom hoses and r12 to r134 fittings for conversion.

 

[RodrigzCrzr]

Ok now I need too chime in.
Great job by the way on your progress of your rig.
What parts does it take to convert from R12 to R134?

 

[roma042987]

I also love the torque which these old school diesels deliver at low RPM. I run the same setup with my 1HZ, 31s and 3.70....and I think this tire size is not ideal...

235/85R16 will make your vehicle much nicer to drive.

I agree it can maybe use just a little longer legs maybe 33s for freeway driving but I'm very happy since I drive like a grandpa anyway. It's very comfortable at 70mph

 

[roma042987]

Lots of progress today finally! Michael Blake (76fj40) rode over and we spent the afternoon working on the rig. Installed the diesel tach in the instrument cluster, it was out of a 24v truck but that doesn't matter all I needed to do was use the 12v illumination bulb. I made a subharness that plugs into the tach pickup in the bellhousing and runs over the trans, one wire grounds on the fender in an existing hole and other plugs into the old tach connector from the old coil. So essentially plug and play using existing chassis wiring. Here are the two tachs in comparison all connections are the same and oddly enough the diesel tach goes up to a higher rpm.

Also got my alternator figured out, apparently it wasn't grounding through the engine mount bracket since it was powder coated. All I had to do was add a ground from the alternator earth terminal over to the fender. I used a nice toyota ground strap with a male/female connector in it for ease of serviceability.