Need Engine identification help!

dkroll · 05-24-2008, 08:45 AM

Hello,
I own a 1989 Comanche with a tired engine. I found a person on the net who has a "Jeep engine" which is a line six and is fuel injected. He is not able to tell me any information of what jeep it has came out of. My question is:
How can I tell the difference between a 4.0 L engine and a 4.0 L (H.O.)engine? Are there physical differences or are there specific Numbers to look on the block? Can I make a 4.0L HO work in my truck without doing too much to swap it (such as the wire harness)? Any info anybody has that will help me with this purchase would help a bunch!
Thank you!
Dkroll

jeepicon-com · 05-24-2008, 09:42 AM

I believe you should look for vacuum lines, I think in 1991 they switched from Renix 4.0L (which you have now) to the HO. Also the intake ports on the HO heads are higher on the HO. And I believe you would have to swap the ECU and header....

XJohnnyC · 05-24-2008, 10:26 AM

Have him look for the casting numbers on the block and cylinder head. Then post them up here.

MTJeepXJ · 05-29-2008, 03:49 PM

If im not mistaken the Renix was TBI(throttle body injection) and the HO is MPI(Multi-port injection). that may be how you can tell.

maddzz · 05-29-2008, 03:51 PM

Quote:

Originally Posted by MTJeepXJ

If im not mistaken the Renix was TBI(throttle body injection) and the HO is MPI(Multi-port injection). that may be how you can tell.

The renix 4.0 is MPI for an 89.

MTJeepXJ · 05-29-2008, 03:55 PM

Oh ok. my bad.

Pete M · 05-29-2008, 06:43 PM

Renix 4.0s tend to have a silver valve cover, HOs tend to have a black valve cover.
Jeep on!
--Pete

dkroll · 05-30-2008, 03:21 AM

Thank you for the info. I found a H.O. and compared it to mine. The intake ports seemed a little higher and I noticed that my Remix has a shroud plate over the manifolds and the H.O. did not. That was the only thing that was different that I could see.
Wish I could find a 91 or 92 Eliminator with a ruff bed as a donor for my parts truck.

SoloCamo · 05-30-2008, 07:20 AM

Quote:

Originally Posted by Pete M

Renix 4.0s tend to have a silver valve cover, HOs tend to have a black valve cover.
Jeep on!
--Pete

Good to know, thanks!

Well if I ever repaint my valve cover again (currently painted black) it's going back to silver

carnuck · 06-04-2008, 01:37 AM

If the manifold is still on it, the Renix has an EGR and the HO doesn't.

05-24-2008, 09:42 AM	#2
jeepicon-com Registered User Join Date: May 2008 Location: US Posts: 80 Profile Gallery Classifieds My Jeeps	I believe you should look for vacuum lines, I think in 1991 they switched from Renix 4.0L (which you have now) to the HO. Also the intake ports on the HO heads are higher on the HO. And I believe you would have to swap the ECU and header.... __________________ [URL="http://jeepicon.com"][CENTER][SIZE="5"][FONT="Century Gothic"][COLOR="Yellow"]jeepicon.com[/COLOR][/FONT][/SIZE][/CENTER][/URL] [FONT="Century Gothic"][CENTER][URL=http://jeepicon.com][COLOR="Yellow"]Jeep Forum and Gallery[/COLOR][/url][/CENTER][/FONT]