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Unread 08-25-2013, 01:38 PM   #1
ALFDMAX
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1989 YJ Wrangler 
 
Join Date: Aug 2013
Location: Bucharest, Romania
Posts: 16
Just another YJ 4.2 to 4.0 swap

Hi,

I recently found a nice YJ 4.2 and I bought it, YJs are quite rare here in Romania... unfortunately the 4.2 engine was damaged so I decided to swap it to a 4.0 Renix from a XJ....

I found all we need to do it in this forum so thanks for that

I have completed the new electricals and now Im putting in the 4.0 engine with a AW4 auto trans, hope next week Ill be able to get its first run

This is the status today... hope next week Ill show you it reassmbled



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Unread 08-26-2013, 01:14 PM   #2
Que89YJ
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1989 YJ Wrangler 
 
Join Date: Apr 2008
Location: Detroit, Michigan
Posts: 13,730
Welcome to the forum! Do you have the renix info to do the adjustments? Go through all the sensor adjustments before you start. What are you using for a fuel pump?
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Unread 08-26-2013, 09:40 PM   #3
ALFDMAX
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1989 YJ Wrangler 
 
Join Date: Aug 2013
Location: Bucharest, Romania
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I think I have got all the info about the renix FI, Ive got the instructions about the bulkhead connector and Ive checked all sensors and replaced most of them... checked the vacuum lines....

Ive used the complete XJ harness for swap but I dont touch the accesories instalation (smallest part of the bulkhead connector)... seems Ive got electric feed where I need

For fuel pumping Ive installed a brand new external pump (Airtex E2000).

I will check tomorrow if its firing...

By the way I found another problem... the AW4 transmission is about 2" longer than the old BA10, so Ill need a SYE for sure and new shafts...

Also I begin to SWAP the D35 3.07 ratio with a 4.56 Chrysler 8.25.

Here the Renix positioned



And here a pic of the actual stage



Thanks for your comments
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Unread 08-26-2013, 09:47 PM   #4
Que89YJ
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1989 YJ Wrangler 
 
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Location: Detroit, Michigan
Posts: 13,730
I have the manuals and tech letters for the renix Cherokee if you need them. Let me know.
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Unread 08-26-2013, 10:00 PM   #5
ALFDMAX
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1989 YJ Wrangler 
 
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Location: Bucharest, Romania
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Thank you so much, sure I will need some support, Ill keep you informed
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Unread 08-29-2013, 11:07 AM   #6
ALFDMAX
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1989 YJ Wrangler 
 
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Location: Bucharest, Romania
Posts: 16
Well, the 4.0 is alive today I start it and it starts instantly.

But I have some minor problems... my oil pressure gauge doesn't work... Im using the 4.2 sensors... maybe this is the reason.

The engine runs well, sounds good, without interruptions and has a quick response to the throttle, but it idles at 1500 rpm instead of 700 rpm... and I dont know the reason... I reviewed all vacuum lines, all electrical conectors of the main sensors... sensors are new brand ones, only the air temperature sensor at mainfoild and the coolant temperature sensor are the original ones but Ive checked them and seems ok...

Im using fuel injectors comming from a 96 ZJ V8... is it possible to be that causing the problem?

Any ideas???

Thanks

A short film with the engine running


Last edited by ALFDMAX; 08-29-2013 at 11:18 AM..
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Unread 08-29-2013, 12:28 PM   #7
remmons
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Great job, especially in Romania!

When I adapted my 1993 XJ 4.0 and my 1988 AW4/NP242 into my 1988 YJ, I had bought a drive shaft from a fellow forum member who had a TJ with an auto trans. Luckily for me the driveshaft went right in as though it was meant to be there. Take some measurements and compare them to an automatic TJ Jeep.

Good luck!
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Unread 08-30-2013, 01:29 AM   #8
ALFDMAX
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Thanks!

Ill try with a TJ shaft, I think youre right, probably is a better solution instead of cutting my shaft.
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Unread 08-30-2013, 12:53 PM   #9
remmons
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Quote:
Originally Posted by ALFDMAX View Post
Thanks!

Ill try with a TJ shaft, I think youre right, probably is a better solution instead of cutting my shaft.
That's exactly what I was trying to avoid. There are several people who upgrade their stock shafts for a Tom Woods or other drive shaft, so I know they're out there, just need to get the specs and match them up.

Since you're in Romania, I am totally unfamiliar with how or what they use for manufacturing running gears, engines, and such, but by the looks of your first post, most all of the parts are the same as it's American counterparts. Fill in your Jeep information and we all will have a better chance on helping out a fellow Jeeper.
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Unread 08-30-2013, 02:34 PM   #10
ALFDMAX
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1989 YJ Wrangler 
 
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Location: Bucharest, Romania
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Most of Jeeps from 1996 and earlier that run in Romania have been imported from USA, so usually they match the USA specs.

The main problem here is how to access any kind of parts, there are not very good american parts dealers here, I prefer to order anything from USA but not all dealers from USA send to Romania, so better said, not with reasonable transport cost... and this is more complicated when we talk about used parts...

So we are using creativity and self manufacturing sometimes

This YJ is my 4th Jeep, but the first Wrangler... before this I owned 2 XJs and this ZJ that I built by myself, but about the ZJ probably is better to talk in another thread...



About this YJ originally was an 1989 Laredo 4.2, imported from Florida, with manual transmission BA10, Dana30 high pinion fornt, Dana35 non c-clip rear, he has a bodylift and ugly longer shackles mounted by the last owner, enought for mounting 35s but without any suspension performance...

Last edited by ALFDMAX; 08-30-2013 at 02:44 PM..
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Unread 08-30-2013, 03:28 PM   #11
remmons
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I totally understand the creativity. Since the TJ started in 1997 you may not have as much luck as what I had expected, but I still wouldn't rule out the possibility that there could still be some level of compatability with what you may have available there. In the end you may just have to cut your shaft after all. I do wish you luck!

BTW, nice looking Grand!
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Unread 09-02-2013, 09:36 AM   #12
ALFDMAX
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Well, Ive fixed the problem with idleling.... Ive taken some days for viewing that on fact I had a bad engine grounding...

Ive clean all engine ground points and Ive added two new ones... Ive adjusted the TPS and problem solved, engine idles well at about 700 rpm.

So I hope this week I will finish all the work.... unfortunately I hve not enought free time to do it faster....
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Unread 09-08-2013, 03:29 AM   #13
ALFDMAX
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Good, Ive fixed all the issues with the 4.0 Renix, its working really fine now

Ive began to swap my D35 rear axle with a Chrysler 8.25, not a great thing but better than the D35... here is really difficult to find stronger axles.

Ive got the 8.25 allready installed, but when I opened it I found that its a Track Lock version, not open carrier... ....... not good because I planned to install a Spartan Locker and now I will need an open carrier for this....





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Unread 09-27-2013, 10:51 AM   #14
ALFDMAX
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Good, I finished the 4.0 SWAP with sucess

Engine runs so fine but I have a transmission issue, with my 4.0 I also have swapped an AW4 auto transmission, and its no shifting if the TCU is connected, if I disconect the TCU transmission sifhts fine manually so I have discarted a mechanic problem.

After reading here a lot of questions about AW4s I tested all sensors and I have a problem with the TPS signal, as you know in the Renix the TPS has two connectors, one for the ECU si another one for the TCU... After performig measurements the connector for ECU gives me correct values but the TCU connector is giving me wrong values, only the power pin is giving me the correct value of 5v, the other two not... signal is giving me 0.7v as well as ground is giving me 0.7v too....

The TPS is brand new (Standard Motors) and my question is if is it possible to be defect from factory?

I will try to get another TPS to do a probe but if anybody has other ideas or can help me with this issue I will be grateful
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Unread 09-27-2013, 02:17 PM   #15
Que89YJ
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You know the renix tps has to be adjusted. It's in the manual.
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