Page updated on 06-22-2018

1994 3.2L DOHC Timing

01-10-2011, 01:43 PM
I have a 1994 Trooper. Bought it used so don't know it's history. Pulled the motor to fix all of the leaky seals. Timing does not seem to match the belt markings or the Chiltons manual I have. Already broke one starter due to backfiring during starting attempt. Pulled the valve covers off and am looking at the valve train. There are two marks on the plate behind the driver side cam sprocket; I've tried timing to both without success. I have also tried timing the cams to what I believe is the initial timing position using the dots on the cam gears in the heads (dots to the left and right, respectively). When these are in position, the timing marks on the cam sprockets point about 45 degrees and about -45 degrees from vertical, respectively for pass and driver side. Timing has always been attempted with crank gear reference mark aligned with line on oil pump. I know the firing order is 123456 so I figure that intake valves for each cylinder should be doing what their predecessor did at 120 degree intervals. This does not appear to be the case. Help please.

01-12-2011, 02:46 AM

Take a look at this thread on PlanetIsuzoo (it covers both DOHC & SOHC):

01-12-2011, 08:04 PM
Looks like all of the timing diagrams for the 3.2L V6s that I have seen before. The reference to the 3.5L DI is a new one to me. I've been assuming it is a 3.2. Is the timing different for the 3.5L?

01-13-2011, 01:39 AM
I presume by 'it' you are referring to the engine in your Trooper?

Check your VIN plate codes:



/quote "THE 3.5 DIRECT INJ ENG THAT CAME ONLY IN THE 04 RODEO AND THE 04 AXIOM" quote/ (capitals in original post)

01-13-2011, 06:41 PM
The VIN does not contain "RLU" or "RLV" in the codes. The full VIN is JACDH58W8R7925385. I am now working on a "dry timing" to see where the marks match. I have positioned #1 piston at TDC based on the timing mark on the lower cover. The left cam gear has been rotated such that #1 intake is just at the point where it engages the valve pusher (rocker?), and the right side cam gear has been turned so that #2 exhaust is at a similar point. I plan to put on the belt and rotate to see if cam gear marks align with anything meaningful.

I have another question. I removed the cam gears to put on new cam seals after we pulled the motor to replace various seals. I marked them so I am pretty sure they are on the correct sides. On the left side, as I face the engine from the front of the vehicle, the cam gear has a belt retainer lip raised on the front of the gear. The right cam gear is simply a gear. Drawings seem to emphasize that this is correct but if they were swapped then maybe that is the problem.

01-13-2011, 08:43 PM
...The full VIN is JACDH58W8R7925385...

The code you're looking for is the Engine code which is also on the VIN plate, not the VIN # itself.

...I am now working on a "dry timing" to see where the marks match. I have positioned #1 piston at TDC...

Forget about traditional piston/valve timing when setting the Isuzu V6 - follow the instructions around setting the timing marks that you will find in the Planetisuzoo thread.

...I have another question. I removed the cam gears to put on new cam seals...

Sorry - I don't know.

EDIT - here's another good thread on Planetisuzoo specifically for the DOHC (look for Jerry's post in capital letters)

Add your comment to this topic!