TBI 5.2 Motor Swap

73Dart · 02-19-2010, 08:57 PM

Well I began the motor swap this morning and so far it has went pretty well. I had the front of the Jeep apart and the old 4.2 removed by 12 noon. That is when things got a little hairy. I found out that the spline count and shaft diameter of the tranny is the same as the one in the dakota. But the pilot bearing in the Jeep tranny is smaller than the Dakota one, so the pilot bearing I bought will not work. A call to a local industial supply store and 2 hours later we had a custom made bearing that wil work. Tomorrow I plan of fabbing up the motor mounts and starting the wiring. I have been Jeepless for about 12 hours now and already I miss it. The bad thing is that today is the first day in about a month that it was warm enough to go topless. Information for those that might be considering a small block mopar swap. The tranny in the 92 and up v6 dakotas is an asian ax-15 just like the jeep. The clutch is the excact same. I installed the clutch from the Jeep on the dodge flywheel. The bellhousing and flywheel from a 3.9l v6 will fit a small block chrysler motor. I was able to use the Jeep clutch, and slave cylinder and the Dakota bellhousing and flywheel. We bolted the tranny to the skid plate and bolted the plate back on the Jeep. The tranny is in the same place it was with the 4.2 and the v8 fits like it was made to fit there. That is good news because now I do not have to make any new driveshafts. Here are a few pics of the work so far.

for-play · 02-19-2010, 10:32 PM

Wow, if that is the same 5.2 that I had in my 99 Dakota it is really going to scoot! I slapped headers on it with a cold air box and promptly split my t-case 4 wheeling. It really woke up. I wish i would have thought of your swap prior to getting waist deep in the chevy swap.

73Dart · 02-20-2010, 06:58 AM

Its not excatlly. It is a throttle body injected that makes 30hp less and 20ftlbs more than the 4.0l Jeep motor. Plus I am leaving the power stock, just looking for the reliability of FI over the carb.

73Dart · 02-21-2010, 02:06 PM

Well I finished up day two of the motor swap yesterday at 3:30. We got the motor mounts fabbed and welded in. Now the motor and transmission are both bolted in. We put the front drive accesories back on the motor, grill and raidator assembly, and the hood back on. This will allow me to move it out of my dads shop while I wait untill I can work on it again. Since I am a full time college student, work full time, have a part time job, a wife and three kids, it will be a couple of weeks before I will work on it again. I will spend that time studing the wiring required for the dash gauges and TBI to work. A few lessons learned are, when you get the dakota bell housing, be sure to get the splash sheild as well. I didn't so I had to make one. Other than that yesterday went pretty well. Here are a few more pics of the progress made.

Overkill motor mounts. They are made of 3/8" flat stock

Homemade splash sheild

73Dart · 02-22-2010, 07:55 PM

One thing I forgot to mention is that the motor came from a 90 B250 conversion van. This is a good vehicle to source a motor from because it already had the center out manifolds, and rear sump oil pan.

73Dart · 03-08-2010, 08:10 AM

Well I finiished it all up on friday afternoon. I have more pics but havent had time to gt them off the camera yet. The wiring wasn' that bad, just took a while to figure out how to incorporate it all. I was able to use the factory sending units which allowed me to keep the stock gauges. I also was able to mount the factory dodge fuel pump to the jeep sending unit and mounted the complete setup in the factory tank. While the tank was out I did the 20 gal mod, and when I filled up I put 18 gal in it. I was able to source the throttle cable, fuses, and relays from the van keepin the cost low. Here is a rundown of the cost.
Motor $0 donated by my father
Dakota Transmission and flywheel $125
Custom made pilot bearing $ 40
Oil cap and fluids $ 20
Oil, filter, antifreeze $ 50
Total $235
For anyone considering this swap it helps out alot to get the whole vehicle the motor came from, because of all the incidentals involved. We were able to use the exhaust pipe from the van to fabricat the one for the jeep. If I had to purchase everything that it eventually needed it would have costed well over $1500 for everything. It runs beautifull now and since my new top wil be here in a couple of days, it will become my DD. I will try to post the rest of the pics in a day or two.

73Dart · 03-09-2010, 07:46 AM

Here are the rest of the pics of my motor swap.
Wires that were removed

Wires that were left

Motor wired into the Jeep

Fuel pickup from jeep

Fuel pump that was removed from the Vans pickup assembly

Fuel Pump installed on the Jeep Pickup

Fuep pump assembly mounted back in tank

73Dart · 03-09-2010, 07:53 AM

Computer mounted on passenger fender under the battery, with splash sheild installed to protect it from possible acid leak.

ASD relay

Starter and Fuel pump relays

Finished product

So far I am loving the result. Alot of people when they look at the Jeep now take a double take when I fire it up. The sound is perfect, not too loud, and deep enough to sound good.

justin6810 · 03-16-2010, 11:08 AM

i just seen where you swap your motor im doing the same with my 95 yj im putting a 5.3 it comes with a trans an tansfer case im putting it in my self but is 3000 to much for tuning,putting gas lines,exc

73Dart · 03-18-2010, 10:36 PM

Filled up for the first time since the swap. Drove 254 miles and put in 15.9 gallons, 15.97 MPG. That is much better than the 11 MPG I was getting with the 4.2l.

mike_breaker_5 · 06-12-2010, 03:24 AM

just here to look back at the motor mounts in a few weeks when i throw my 5.2 in.

**MoparFreak69** · 06-12-2010, 01:05 PM

I would be concerned about the welds for those mounts. They do not look like they penetrated the frame or that material very well. You have to be very careful how you weld 2 different thickness materials together.