93 did not have a cam synchronizer?? your truck must be a late 93 with CA emissions?? Does your engine also have EGR?
Has your engine been replaced before?
Allright now that is sorted out kinda, forget what you read about the old 94/95 glass window style synchronizer.....just toss it out of your head.
Pretend you are all 1996 in there. I have dropped probably 25-30 cam synchros into 4.0 ohv engines over the years, so you can just listen to me
Bring cylinder number one (pass side front cyl) to top dead center on COMPRESSION STROKE
Now there are 2,000,000 ways to find TDC on comp stroke, but here is how I do it on Ford 4.0, 5.0, ATV engines, snowmobile engines, etc.....it always works this way
Remove #1 plug
put 21mm socket on front of crank balancer with ratchet.
Wet a finger and stick it in the #1 plug hole.
Bar engine over by hand (clockwise) until air rushes passed your finger....this is the compression stroke.
Now with a flashlight you can actually watch the piston come up to the top....and as soon as it reaches the top and just starts to change directions STOP.
That is TDC compression stroke.
(some people like to use a small screwdriver for this so they can tell when the piston reaches top, that works too) For me I find with the tire removed I can easily see in the #1 plug hole.
However you do it, just do it.
You can check the mark on the crank balancer if you like, the little pointer should be right at the 0 or damn close.
Now you are ready to drop in the cam synchro with alignment tool
The way this works is the cam synchro gear with align with the drive gear on the cam. As you drop the synchro down and in it will rotate, as the gears mesh the synchro will turn clockwise. The synchro will rotate about 15-20 degrees as it drops down. Exactly like stabbing a distributor from yesteryear.
For you new kids a distributor was an old spinny thing that sent spark from one coil to several plugs by actually spinning in circles and making electrical contacts....I know I know you can only see them in museums anymore.
When the synchro is finally fully seated all the way down the alignment tool should point like this:
We will call this the "home position"
the picture above I took years and years ago is of a 98 ohv engine, this pictures shows up just about anytime you google 4.0 cam synchro
Now here is where people over think this
you see the cam sensor can end up close to this picture............
but not exactly and
STILL BE ON THE CORRECT TOOTH for timing.
How?? you ask.
Well it all depends on where you stopped the piston at TDC
If you went to 10 degrees after TDC then the cam synchro would be locked down a little closer to center, if you were just a few degrees before TDC then it would be locked down a little closer to the passenger head....
both home positions would still be correct
because in both cases you are still on the
correct cam gear tooth.
Co you can spend all day trying to get the cam synchro to be exactly 60 degrees from centerline yadda yadda yadda or you can just know you are on the correct tooth and call it good.
It would be
VERY DIFFICULT to be a tooth off because the cam synchro will rotate so far it wont even be close to our "home position" anymore. Each tooth results in like 12-20 degrees of rotation
