Cam Syncronizer Positioning How-to

I knew I had this sitting around somewhere....

FIND Top Dead Center #1
Start by knowing you have your engine on top dead center number one (the cylinder most forward on the passenger side). The pointer from the block will be at the zero point on the harmonic balancer. Also, both the intake and exhaust valves will be fully closed. If you are one turn off the valves will be in the overlap position, both slightly open. This is easiest to discern if you have the valve cover off that side and can observe valve action as the engine is turned. It rotates clockwise from the front of the car. As you turn the engine clockwise, look for the exhaust valve to open. Then it will close and just before it's there the intake will open. Continue turning engine until the intake is fully closed. Now keep going a bit until you get to 0° on the engine pointer. You're there. TDC #1.

Crankshaft LOCATION, STOCK BALANCER
There is a groove across the stock harmonic balancer about 3/4" past 0° as you continue to turn the engine clockwise past TDC # 1. You want your pointer to be right in the middle of that. That is 26° ATDC.

Crankshaft Location, BHJ BALANCER
In the case of a BHJ custom balancer, any score on that side of the timing tics is likely to be wrong for this. Instead, take the measurement from zero to 26 BTDC, and go the other way (toward the passenger side) that far from zero to make a mark. That is where your pointer should be at.

Install CAM SENSOR
Insert the body of the cam sensor into the engine so that the port strikes an angle about 30° forward of the line perpendicular to the crankshaft (an imaginary line across the front of the engine parallel to the front edge of the timing cover). You can rotate the body forward and back a few degrees from this position and this is how you do the final adjustment.

Now you should check to see that the "U" on the base plate that sticks up from the rotating base plate is more or less inverted as you look on from the front of the car. It may take a couple tries, but pull the body out enough to be able to rotate the plate roughly into position, then re-insert, and as the sensor drive gear engages the cam gear the base plate will move some. Observe the movement so you can compensate on the next try. You'll get it to engage on the right tooth.

LOCATION, LOCATION, LOCATION
Here is the important part. When you have the body fully against the timing cover, the left edge of the inverted "U" must be exactly aligned with the very center of the sensor port. There is a raised score on the sensor cap where you want it to be (but you won't be able to have it on while you do this) The Ford spec is +/- 5° on this setting, but your eye is MUCH better than that.

You want it to get the left edge of the inverted "U" close to lining up with the score on the sensor port during the body install - with the center score in that 30 degree forward position. Then you can rotate the body just a few degrees forward or back to get it perfect. Then tighten down the body lock screw and now you can install the sensor cap.

Here is how it should look:
 

Attachments

  • cam sensor.jpg
    cam sensor.jpg
    19.8 KB · Views: 2,508
  • Camshaft Sensor Install.jpg
    Camshaft Sensor Install.jpg
    21.1 KB · Views: 2,201
I knew I had this sitting around somewhere....

FIND Top Dead Center #1
Start by knowing you have your engine on top dead center number one (the cylinder most forward on the passenger side). The pointer from the block will be at the zero point on the harmonic balancer. Also, both the intake and exhaust valves will be fully closed. If you are one turn off the valves will be in the overlap position, both slightly open. This is easiest to discern if you have the valve cover off that side and can observe valve action as the engine is turned. It rotates clockwise from the front of the car. As you turn the engine clockwise, look for the exhaust valve to open. Then it will close and just before it's there the intake will open. Continue turning engine until the intake is fully closed. Now keep going a bit until you get to 0° on the engine pointer. You're there. TDC #1.

Crankshaft LOCATION, STOCK BALANCER
There is a groove across the stock harmonic balancer about 3/4" past 0° as you continue to turn the engine clockwise past TDC # 1. You want your pointer to be right in the middle of that. That is 26° ATDC.

Crankshaft Location, BHJ BALANCER
In the case of a BHJ custom balancer, any score on that side of the timing tics is likely to be wrong for this. Instead, take the measurement from zero to 26 BTDC, and go the other way (toward the passenger side) that far from zero to make a mark. That is where your pointer should be at.

Install CAM SENSOR
Insert the body of the cam sensor into the engine so that the port strikes an angle about 30° forward of the line perpendicular to the crankshaft (an imaginary line across the front of the engine parallel to the front edge of the timing cover). You can rotate the body forward and back a few degrees from this position and this is how you do the final adjustment.

Now you should check to see that the "U" on the base plate that sticks up from the rotating base plate is more or less inverted as you look on from the front of the car. It may take a couple tries, but pull the body out enough to be able to rotate the plate roughly into position, then re-insert, and as the sensor drive gear engages the cam gear the base plate will move some. Observe the movement so you can compensate on the next try. You'll get it to engage on the right tooth.

LOCATION, LOCATION, LOCATION
Here is the important part. When you have the body fully against the timing cover, the left edge of the inverted "U" must be exactly aligned with the very center of the sensor port. There is a raised score on the sensor cap where you want it to be (but you won't be able to have it on while you do this) The Ford spec is +/- 5° on this setting, but your eye is MUCH better than that.

You want it to get the left edge of the inverted "U" close to lining up with the score on the sensor port during the body install - with the center score in that 30 degree forward position. Then you can rotate the body just a few degrees forward or back to get it perfect. Then tighten down the body lock screw and now you can install the sensor cap.

Here is how it should look:
Thank-you for the photos and the explanation. After rebuilding my '94 SC engine, I'm having problems getting it started. It looks like I've installed the synchronizer 180 degrees off so will look at it and install according to your photo. I have the complete Service Manual and know about the minimum 6 degree and max 30 degree ccw rotation, but it would not start.
 
Back
Top