Greenville, SC FJ40 Engine Swap - Need Help Finding a Mechanic

[SC Forester]

I am pretty sure that is not the Toyota rear axle. This thing has a much higher first gear than other ones.

 

[pb4ugo]

Yep, looks like a dana 20 case, I see the torq arm in the pic too, which would indicate it probably has the j**p tranny. The weak link is the rear end, it looks like a mini truck rear. The cheap conversion would be to put a wide ratio(granny gear) T18 trans and a dana 20 case if the engine runs good.. If your current bellhousing is out of a cj it should be already drilled for the T18 to bolt up. Originally, jeep used the skid plate as the cross member to hold the trans and t/case. FYI. You can adapt dana 18 gears into the dana 20 case which will get you a 2.46:1 lower range rather than the stk 2:1 that s in the stk 20 case. You'll need to source some parts from an old bronco dana 20 case to do it though. You can also twin stick the case. 1 stick will operate the frt end for frt dig, and the other will operate the rear. FYI, I currently run In my 40, a SBC, sm420 tranny, and a twin sticked dana 20 with the dana 18 gears. I centered my stk 40 rear end because I already had 4:88 gears and a Detroit locker in it.

 

[SC Forester]

Yep, looks like a dana 20 case, I see the torq arm in the pic too, which would indicate it probably has the j**p tranny. The weak link is the rear end, it looks like a mini truck rear. The cheap conversion would be to put a wide ratio(granny gear) T18 trans and a dana 20 case if the engine runs good.. If your current bellhousing is out of a cj it should be already drilled for the T18 to bolt up. Originally, jeep used the skid plate as the cross member to hold the trans and t/case. FYI. You can adapt dana 18 gears into the dana 20 case which will get you a 2.46:1 lower range rather than the stk 2:1 that s in the stk 20 case. You'll need to source some parts from an old bronco dana 20 case to do it though. You can also twin stick the case. 1 stick will operate the frt end for frt dig, and the other will operate the rear. FYI, I currently run In my 40, a SBC, sm420 tranny, and a twin sticked dana 20 with the dana 18 gears. I centered my stk 40 rear end because I already had 4:88 gears and a Detroit locker in it.

The 360 ran good until a few months ago. It just started bogging down and cutting off when it got up to 170 degrees. I replaced the fuel pump, fuel filter, and fuel lines. That didn't do a thing so I got rid of the old distributor/ignition set up and installed an HEI distributor. Got it timed and it ran great until it hit 170 degrees then it started bogging down and cut off again while driving. I have no clue what that problem is. Then the starter crapped out and I got a replacement at Advance Auto. Well now that is a whole new problem. The Advance replacement would not engage the flywheel. I took it back but they had already sent off my core. Bought a slightly different model on Rock Auto and have the same problem. Went to the LKQ today and pulled one off a 1978 CJ5 and it does the same thing. Just spins and won't grab the flywheel. I guess the original one was shimmed or grinded down so it would reach the flywheel? Anyways, I am getting tired of dealing with the 360 when I want to put a trusted Chevy 350 in it. I am dumping money in a motor that I don't really want.
So what do I need to do now? I may have a lead on an FJ40 4 speed and transfer case. Possibly an FJ40 rear axle too. I will need to get all of that for the Chevy, right?

 

[SC Forester]

Or should I try to find a completely Chevy drive line now - Chevy transmission, transfer case, rear end?

 

[pb4ugo]

To do a 350 swap with the fj40 4 speed and tcase you need a bellhousing for SBC to fj40 tranny, engine mounts, propeller type trans cross member, proper clutch p/plate and throw out bearing along with the t/out bearing fork and hub. You'll be altering the drive shafts to fit. Advanced Adapters makes a kit or @Downey sometimes has some of his old kits available. Downey is on this site and is a supporting member. Hopefully he'll chime in shortly, he'll get you pointed in the right direction. Yes, your tranny options are very diverse. Any GM tranny then an adaptor for the t/case. What are you plans for this 40? Wheeling, street driving, hard core, moderate?

One issue I see in your current setup, is the fuel line. You should run the lines like AMC ran them. The fuel line should comes off the pump then into a stk CJ fuel filter, it has 1 inlet and 2 ports on the out put side. 1 is for the return line and the other goes to the carb. Fro some reason running the line like you have the engine likes to load up and run rich. . As for starter, what's the flywheel gear look like? In my experience, There are no shims for it. You might try a starter for wagoneer or some other application that AMC used with the 360.

 

[pb4ugo]

You may need to get a stk or aftermarket fj40 rad, in your engine pic it looks like your top hose connects on the passenger side. Hard to tell in the pic though.

 

[SC Forester]

To do a 350 swap with the fj40 4 speed and tcase you need a bellhousing for SBC to fj40 tranny, engine mounts, propeller type trans cross member, proper clutch p/plate and throw out bearing along with the t/out bearing fork and hub. You'll be altering the drive shafts to fit. Advanced Adapters makes a kit or @Downey sometimes has some of his old kits available. Downey is on this site and is a supporting member. Hopefully he'll chime in shortly, he'll get you pointed in the right direction. Yes, your tranny options are very diverse. Any GM tranny then an adaptor for the t/case. What are you plans for this 40? Wheeling, street driving, hard core, moderate?

One issue I see in your current setup, is the fuel line. You should run the lines like AMC ran them. The fuel line should comes off the pump then into a stk CJ fuel filter, it has 1 inlet and 2 ports on the out put side. 1 is for the return line and the other goes to the carb. Fro some reason running the line like you have the engine likes to load up and run rich. . As for starter, what's the flywheel gear look like? In my experience, There are no shims for it. You might try a starter for wagoneer or some other application that AMC used with the 360.

I appreciate all the info. I am not an experienced mechanic at all and this is very helpful. I have seen the AA kit for the 4 speed. I thought I would be looking at the one for the 3 speed originally but I now see that I have a Jeep drive train the whole way through. I do not mind changing the whole thing to Chevy from the engine back. I am going to need to change the rear axle though now either way I go though, right? I bought this FJ40 for street driving and the occasional trails in the Carolina mountains. It won't be seeing anything extreme.

As for the current Jeep problem, I will look into a new fuel filter. That could be why it is running rich. I can get it to idle fine (before the starter issue) but then it starts stinking of fuel bad and then it bogs down and cuts off. The flywheel looks great. None of the starters I have installed (3 of them) are reaching out and spinning the flywheel.

 

[pb4ugo]

Well,,,, You are sort of at a cross road. If you swap out the rear end to a fj40, then you probably need to use the fj40 t/case. The 40's rear end is offset to the passenger side, and the 40 t/case has a offset rear output to match. So, tranny options would be using the stk 4 speed, or you could possibly use a sm465, or a sm420, which are GM tranny's and then adapt the t/case to the tranny. The plate adapters , I believe, are a little rare. A Toyota 4 speed, either a 41 or a 42 shift nice and one of them has a lower 1st gear. I'm not sure which one it is. The lower gear would be nice in off road situations. The GM/SM tranny's shift like a truck. The gates are more defined and I believe both of them have a lower 1st gear than either of the Toyotas. The other options would be using a Toyota 5 speed and a split case, or use or make a centered rear diff and adapt a GM/USA tranny's 4 speeds or 5 speeds and probably use something like a dana 300 t/case, which is a centered rear output like the dana 20. The length of the tranny and t/case become important in any swaps. I'm sure folks will chime in on the specifics of the various Toyota trannys.

 

[SC Forester]

Well,,,, You are sort of at a cross road. If you swap out the rear end to a fj40, then you probably need to use the fj40 t/case. The 40's rear end is offset to the passenger side, and the 40 t/case has a offset rear output to match. So, tranny options would be using the stk 4 speed, or you could possibly use a sm465, or a sm420, which are GM tranny's and then adapt the t/case to the tranny. The plate adapters , I believe, are a little rare. A Toyota 4 speed, either a 41 or a 42 shift nice and one of them has a lower 1st gear. I'm not sure which one it is. The lower gear would be nice in off road situations. The GM/SM tranny's shift like a truck. The gates are more defined and I believe both of them have a lower 1st gear than either of the Toyotas. The other options would be using a Toyota 5 speed and a split case, or use or make a centered rear diff and adapt a GM/USA tranny's 4 speeds or 5 speeds and probably use something like a dana 300 t/case, which is a centered rear output like the dana 20. The length of the tranny and t/case become important in any swaps. I'm sure folks will chime in on the specifics of the various Toyota trannys.

I’m thinking I may just get the Jeep running and sell it as it is. I am not sure if it would make sense economically to swap out everything after the PO put all this in. It’s a nice rig but it’s gonna cost a fortune to swap out everything.
It makes me wonder if the front is Jeep too. Wouldn’t it be for the 4wd to work correctly?

 

[pb4ugo]

I’m thinking I may just get the Jeep running and sell it as it is. I am not sure if it would make sense economically to swap out everything after the PO put all this in. It’s a nice rig but it’s gonna cost a fortune to swap out everything.
It makes me wonder if the front is Jeep too. Wouldn’t it be for the 4wd to work correctly?

We would have to see pics of the frt end to determine what it is. j**p cj's typically have a 5x5 1/2 lug pattern and a weak ass dana 30 frt end. What yr 40 do you have? is it a disc brake frt end? Does have closed knuckles. It could very well have a 40 frt end. Someone may have just changed the driveshafts u joint flange to bolt to the Toyota frt end, just like they did for the rear. I'd also confirm the rear and frt have the same gear ratios. I looked into starters and flywheels for AMC engines and they all seem to use the same starters and flywheels. I don't get why the starter doesn't work for you. Does the starter drive jet forward when power is supplied? Like I said b4, the most economical 4 speed swap would be to adapt a cj T18 trans with the dana 20 still attached to it, if you have the proper bellhousing. For now you could keep the rearend as it is. The cj T150 3 speed was a decent tranny other than not having a low 1st gear,

 

[pb4ugo]

Did the previous owner do the engine/driveline swap? If so, I'd ask him what parts did he use.

 

[SC Forester]

Did the previous owner do the engine/driveline swap? If so, I'd ask him what parts did he use.

It was the previous previous owner that did the work.

 

[SC Forester]

You may need to get a stk or aftermarket fj40 rad, in your engine pic it looks like your top hose connects on the passenger side. Hard to tell in the pic though.

Yup

 

[SC Forester]

Passenger side

 

[SC Forester]

We would have to see pics of the frt end to determine what it is. j**p cj's typically have a 5x5 1/2 lug pattern and a weak ass dana 30 frt end. What yr 40 do you have? is it a disc brake frt end? Does have closed knuckles. It could very well have a 40 frt end. Someone may have just changed the driveshafts u joint flange to bolt to the Toyota frt end, just like they did for the rear. I'd also confirm the rear and frt have the same gear ratios. I looked into starters and flywheels for AMC engines and they all seem to use the same starters and flywheels. I don't get why the starter doesn't work for you. Does the starter drive jet forward when power is supplied? Like I said b4, the most economical 4 speed swap would be to adapt a cj T18 trans with the dana 20 still attached to it, if you have the proper bellhousing. For now you could keep the rearend as it is. The cj T150 3 speed was a decent tranny other than not having a low 1st gear,

Looks like the Toyota front axle. How would the 4wd work though with all the Jeep stuff?

 

[pb4ugo]

It looks like a 40 frt end with disc brakes along with a mini truck rear. The j**p stuff is just a 4wd platform, it should work fine. All that matters drive line wise, is if the frt and rear axles have the same gear ratio. The pass side rad hose just means the op changed the rad to conform with engine design. You need to figure out the starter issue. Is the starter you purchased a j**p starter. Got pics of the hole it goes into and the starter? It should be a ford style starter without a solenoid on it. It should have just 1 terminal on it. Get some jumper cables and ground the case and supply power to the 1 terminal and see if the starter gear jumps forward and spins. Put your foot on it or clamp/wedge it a bit, and touch the terminal with + cable.

 

[SC Forester]

It looks like a 40 frt end with disc brakes along with a mini truck rear. The j**p stuff is just a 4wd platform, it should work fine. All that matters drive line wise, is if the frt and rear axles have the same gear ratio. The pass side rad hose just means the op changed the rad to conform with engine design. You need to figure out the starter issue. Is the starter you purchased a j**p starter. Got pics of the hole it goes into and the starter? It should be a ford style starter without a solenoid on it. It should have just 1 terminal on it. Get some jumper cables and ground the case and supply power to the 1 terminal and see if the starter gear jumps forward and spins. Put your foot on it or clamp/wedge it a bit, and touch the terminal with + cable.

Where does the return line go on the AMC setup off the fuel filter? I’m going to work on getting the current setup running again for now. The starter issue has to be something simple in my wiring after installing the HEI distributor.

I still want to install my 350 though. Now that I know it’s all Jeep would I be better off going with a Chevy transmission and transfer case? Would that even work with this rear end?

 

[pb4ugo]

The j**p filter goes in the same place as your glass filter. You'll have to run a return line to the gas tank. You'll want a filter for a j**p cj with a v8, maybe 1978 or 79. Your 74 FJ40 originally should have had a feed and return lines. They ran down the pass side along the frame rail. Maybe the metal lines are still there. Here's pics of the j**p filter and and image from cool cruisers of texas, on how the 40 line ran at the tank. The center nipped goes to the carb, the 2nd is the return. It should relieve pressure going to the carb.

 

[SC Forester]

The j**p filter goes in the same place as your glass filter. You'll have to run a return line to the gas tank. You'll want a filter for a j**p cj with a v8, maybe 1978 or 79. Your 74 FJ40 originally should have had a feed and return lines. They ran down the pass side along the frame rail. Maybe the metal lines are still there. Here's pics of the j**p filter and and image from cool cruisers of texas, on how the 40 line ran at the tank. The center nipped goes to the carb, the 2nd is the return. It should relieve pressure going to the carb.View attachment 2109400View attachment 2109401

This is plugged off at the tank. Should the reserve go here?

 

[pb4ugo]

Yes. That should be the port for the return line. There should be a hole in the floor near there to feed the line thru. The might be a metal line that ran down the pass frame rail to the engine compartment.