The ECS shim tool is designed to be used with a veneer caliper. Start by measuring your shim tool, it should measure 0.60 inches. Now insert your tool into the shim be measured. for 2 valve motors the large end goes into the shim ware that collars normally sit. For 4 valve motors the small and is used in and goes in where the keepers would sit. Now measure the shim an shim tool  together as one.  Subtract the size of your shim tool (0.60 inches) from this measurement. You now have the size of your shim. 

Technicians: I highly recommend you buy a Digital caliper to use with our shim tool, to save even more time. With the digital caliper measure the shim tool, zero your caliper with this measurement, that way as you  measure each shim you don't have to do any adding and subtracting and saving you a lot of time on every service. Our tool should pay for itself on your first service!
Other tools available from ECS