[Jim Williams]

Well, I guess this question doesn't hold much interest for the engine gurus. So I'm gonna take a hack at answering my own question. My take is, since there is no wear limit spec on the backlash (my thought is that the numbers in the table in the spec book are installation tolerances and not wear limits), that it's not really not all that important. I measured 0.12 mm backlash, and the intermediate gear measured 137.22 mm - within spec. So what do I compare the 0.12 mm to?

If I am getting 0.12 mm of backlash, my math tells me this is equivqlent to about 0.2 degree at the crankshaft if you could hold the intermediate gear immobile ( crank gear has roughly a 76.2 mm diameter, circumference = pi x D = 249.4 mm. (0.12/249.4)x360 deg = 0.173 deg). Or if you hold the crank immobile, half that, or 0.1 degree at the cam.

Now, how much would this affect the cam timing? Since trying to move the crank by 0.2 degree is dam near impossible, even using a degree wheel, I'm thinking the answer to this one is, so little you can't measure the effect on cam timing either.

So gear noise, if any, would seem to be the only effect on engine operation, unless I'm missing something else.

If anyone else has anything new to add, please post.