PA Highlander's Jeep Site

YJ 4.3L Engine Swap
Up JK Tech YJ 4.3L Engine Swap YJ Bumper Thumper XJ TJ Flare Install XJ Rock Rails

Here is a photo narrative of my 4.3L engine conversion.

I used the entire driveline from a 1989 Chevy S-10 Blazer - 4.3L V-6, 700R4 automatic transmission, and NP231C transfer case. The motor mount used was the Advanced Adapters bolt in saddle mount for a 5.7L in a YJ chassis. 

Well, as of Friday May 27 2005 the YJ is up and running on the 4.3L engine. All seems to be working well at this point. I had to modify the 'Y' pipe from the V-6 to clear the front driveshaft - I had a custom pipe bent. I have posted my wiring diagrams from splicing the 1989 Chevy S-10 engine harness to my 1992 Jeep YJ chassis harness. I removed the entire engine portion of the Jeep harness (i.e. injectors and sensors). I did not use the mechanical fan on 4.3L and opted for a 2000 cfm electric fan sitting in front of the S-10's radiator. (yes, I used the S-10 radiator - it was way cheaper than a custom conversion radiator)

The wiring diagrams are posted for information only I cannot warranty their accuracy, every installation will vary. USE AT YOUR OWN RISK! (standard legal disclaimer - don't be stupid and blame it on me!)

A few key points ...

The Chevy fuel pump MUST be used - the Jeep TPI system pumps at 19-39 psi and the Chevy TBI system operates at 9-13 psi. The engine will not start with the fuel pressure too high. 



Custom driver's side of Y

"Finished" engine bay





Wiring Diagram

Links to .jpg file

YJ with part of blown 2.5L


AA saddle mount





ECM sub feed and ALDL

Broken alternator bracket


Shifter placement

Chevy and Jeep fuel pumps


2WD trial runs

Left side S-10 crossmember on YJ


Current Photos

Piece of factory pipe left

2000 cfm Fan


Project Photos

'89 S-10 Blazer - Donor




Set everything together



ECM & DRAC in glovebox

Broken alternator bracket

Sub feed fuse panel

Chevy Y pipe to an XJ cat

Chevy on Jeep assembly



Right side crossmember

Together & Clean - bling, bling!



Shorty Cat and Turbo Muffler

Optima power with disconnect




Wiring Diagram

Links to .doc file

YJ gutted


Bob's hoist

Cut everything to clear the way!


S-10 bulkhead connector



Jump start

B&M shifter cable routing

cat to YJ Pacesetter muffler

Close up



Hack job on the Y pipe





All material copyright 2009, or used with permission or linking

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