by Bruce Murray

It is imperative that the camshafts are not moved during the actual fitting of a timing belt. I have made a tool that helps me during the timing belt replacement process. It consists of two 6-point 22mm 1/2" drive sockets, two 1/2" coach bolts, two nuts, and one piece of aluminum. The components are shown in Figure 1.

One of the sockets has its hex end cut back by 1/8" and its drive end by 1/4". Each coach bolt has its head turned down to 0.85" diameter by 0.15" deep (you will need a lathe to do these modifications). One of the nuts is cut down to 3/16" high. One bolt is shortened so that it does not protrude beyond the cut nut. Since the clearance between the rear camshaft and the body is so small, these modifications are necessary for use on a 164. On a Milano or GTV6, they’re not.

The 1" x 3/8" x 9.5" aluminum bar has two 1/2" holes located 8.15" apart. With the parts assembled (see Figure 2) and with the nuts just snug, slip the sockets over the camshaft bolt heads and tighten the nuts. Detension the old belt and you can slide it off and out of the car without removing the cam clamp.

Obviously, it would be more elegant to make both sockets the same, but it’s not necessary, as shown in Figure 2.

After TDC is set and the clamp is in place, the camshafts cannot be moved. I found it helpful, when fitting the new belt, to turn back the camshaft just a tiny amount to get the teeth to engage on the crank pulley and front cam pulley. Once the new belt is on and the tensioner initially set, the cam tool can be pulled off without loosening its nuts.