So I picked up an IMI 902 starter from Good Vibrations Motorsports and it won't start my 572 with a 10-71 blower. The starter has a 2 kw motor. This is the second starter I bought from GVM. The first one was an IMI 102n with 1.4 kw motor which the GVM tech recommended but both will not start my engine. GVM says they never get any complaints about the IMI starters but when I called the IMI tech they recommended the 902 or 935. So GVM let me trade the start plus the additional cost between the two starters. If I take the IMI 902 back to GVM they are going to hit me with a 10% restocking fee so I want to make sure that I have done everything possible to make sure it's the starter.
I measured the gap between the pinion gear and the back side of the ring gear and it was tight at .020" so I added the circular shim and the gap is now .098" (should be .040" to .100"). I measured the backlash and it's .022" with a .015" mounting block shim. The IMI 902 turns the engine over but it makes a ticking noise just like the 102n did when I tried that one. I have started the engine with two other used starters Hitachi and Tilton and the engine starts right up. So what's the deal has anyone else have problems with IMI starters?