Topic: Help needed again guys!

[bammerman]

I found a 4.0 engine without wiring.  79k miles.  Came out of a 97 Cherokee, been sitting a year with no oil so head gasket needs to be replaced he said.  selling it for 150.00.  I don't think I want to pass this up, what do you all think?  If it has no wiring can i pull the wiring harness out of a Cherokee and computer or can I still use my old computer?  I looked through the forums but not being a gear head it is all cryptic to me.

Do I have to change out axel's too? The guy is giving me a list of the parts I need to do the swap after i get off of work.  I will post the list, but a running 4.0 for 150.00 seems worth it to me.

[Jeffy]

You really need to look into what it's going to take to put that in your Jeep before buying it.  You cannot reuse your 2.5L's computer.  The engine is the least of your worries.  Engine mounts, transmission, transfer case input shafts, driveshafts, etc...

[Sine Deviance]

Yeah, what Jeffy said.

This is the reason that swapping to a 4.0L isn't the best option. The power gains vs. time, cost, and effort just aren't worth it. It's better to spend that time, money, and effort to swap to something bigger.

Swapping to a V8 would be more cost-efficient and will probably cost the same amount of money, excluding the engine of course.

There's just no substitute for CID.

[Jeffy]

Yeah, what Jeffy said.

This is the reason that swapping to a 4.0L isn't the best option. The power gains vs. time, cost, and effort just aren't worth it. It's better to spend that time, money, and effort to swap to something bigger.

Swapping to a V8 would be more cost-efficient and will probably cost the same amount of money, excluding the engine of course.

There's just no substitute for CID.

Honestly, I think the 4.0L is an OK swap since it allows you to reuse a lot of what you already have on your 2.5L onto the 4.0L.  You won't need to alter your exhaust which is also nice.  Might consider doing a 4.2L crank to get the CC's up.

[bammerman]

Damn way more than I thought.  Figured I could use the existing parts off of my 1990 (tranny, transfer case, drive shaft, etc.. etc...) I was on another forum and they said it is easy swap but it is for all types of jeeps. I think I trust this site a bit more since it is focused on the 4cyl.  Figured minus the wiring harness and electrical it is just plug and play.

on a side note, Jeffy how much would it cost me for you to make one of those plates for my YJ for my switches?

**** edits ****

I guess I was wrong it came out of a 1997 wrangler not cherokee

[Jeffy]

on a side note, Jeffy how much would it cost me for you to make one of those plates for my YJ for my switches?

It's just some 20 gauge steel cut to fit the stock switch panel then taped onto it.  Then you choose your switches and pattern them.  I went with a 2x3 setup since that takes up jsut about all the space available.  Depending on the switches you might have to get creative with the layout as the block on the back of the switches can interfere with your wiring if you use plugs.  Probably best to add some wires to the switches and have the plugs off of many a 6-8" led.

If you really want me to make a panel PM me.

[bammerman]

I shot ya a PM (i think says 0 in outbox).

Spoke with the guy about the engine says if I have the AX5 it will bolt right on, if not I might need a new bell housing.  Need exhaust manifold and down pipe and headers.  has everything else on it.  he said the engine will bolt onto my motor mounts so none needed.  Its off craigslist so I am kind of leary but he had engines and crap all over so he might know what he is talking about.

[Jeffy]

I shot ya a PM (i think says 0 in outbox).

Spoke with the guy about the engine says if I have the AX5 it will bolt right on, if not I might need a new bell housing.  Need exhaust manifold and down pipe and headers.  has everything else on it.  he said the engine will bolt onto my motor mounts so none needed.  Its off craigslist so I am kind of leary but he had engines and crap all over so he might know what he is talking about.

The guy is wrong...

You cannot bolt an AX-5 to a 4.0L.  There is no bell housing for it.  You will need to swap in an AX-15 bell housing or a NV3550.  The other option is to use a 2.8L bell housing and bolt on an SM620 or other 4-speed.  Then there is the aftermarket NV4500 bell housing.

The motor won't bolt to your motor mounts either.  The 2.5L's are in a different location.  Not to mention, the passenger side is completely different.

Lot of things to consider with the swap and really, if you want it to go smooth you need a complete Jeep or at least most of it then you can swap parts back and forth till you get it running.  Then you won't have to search for parts.

I forgot another thing you'll need is a new speedometer/tach as they are engine specific.  Your RPM's will be way off.

[dwtaylorpdx]

Its cheaper to go buy a 4.0 jeep, swap anything off your old jeep that's too cool to lose and sell whats left of the old one...
97 is OBDII, But you likely need the entire wiring harness, ecu and sensors from a 4.0 same year or newer than yours.
The head gasket is a bad sign, sitting does not make them go bad, the engine likely got pulled because of the blown gasket or worse.

The frame on the 2.5 and 4.0 are NOT the same in the front, you'll be welding motor mounts, need a 4.0 radiator.
The 4.0 does not bolt to the ax5 and even if it did it would last a week. I'm on #4 in 200K miles. With the 4cyl and
that's about 1/4 off-road miles.

Its your dime and your time but no way I'd bother...

Dave

[Castr8r]

I'd walk away from this deal; too many mis-statements if not outright lies.  I'm of the opinion that this goes beyond ignorance and/or stupidity.  If you really need more power, why not sell yours and buy a six?  It's a lot less hassle and almost certainly a lot cheaper.  The Wranglers are out there, just start looking.

[sharpxmen]

this is in regards to the AX-5: the 4.0 clutch has different splines compared to the input shaft on the AX-5, you can't use the 2.5 disk as the flywheel and pressure plate are different (and you need the 4.0 flywheel) so i am pretty sure you need an AX-15 or NV3550 transmission or frankenstein something with the clutch disk (although in that case you'll also need the pilot bearing as that one is also different).

[bammerman]

Ugh I think I will walk away from it or just buy the engine and try to flip it on ebay :D

[drunkencityworker]

I was told somewhere that the 2.5 comp can be used just 2 wires need to be added and it would have to be a manual trans after swap. Sorry I will try and find something to back this up

[sharpxmen]

I was told somewhere that the 2.5 comp can be used just 2 wires need to be added and it would have to be a manual trans after swap. Sorry I will try and find something to back this up

i think the person was referring to the wire harness - you need the missing 2 injectors wired, that's all as far as i know.
Although the computers look the same from the outside the firmware (flashed code) on it is different and engine specific so i'm pretty sure it won't work but if someone knows otherwise i'm really interested to find out

[dwtaylorpdx]

Interesting idea, the FSM wiring diagram does show Cyl 5 and Cyl 6 on the 4 cyl computer.

Gotta wonder how close it is software wise...

Hmm

Dave