So I have to have some one give the the motor throttle while holding the timing light at harmonic balancer , until what stops moving ? new to this total timing thing . I just usually set the idle to 1200 and adjust it to 10 degrees . So my timing could be off? Why is this different for
boats.
The difference is within the distributor and engine, and to some degree, personal preference. Within the distributor there is a mechanical advance mechanism that consists of weights and springs, and many times(as with an MSD distributor, or others) a bushing that limits travel. That travel determines how much additional advance is brought in as the distributor spins, and the weights overcome the strength of the springs.
What all that means is that you should be checking your total timing, after all of the advance is in. I deal with mostly Chevy engines, and they tend to like 34-36 degrees total timing, on a carbureted engine, with less total advance preferred on a forced induction (blown or turbo) engine.
