[Marshall V. Daut]

"Anyone think the timing gear could be a tooth off and still run ok?"

A Model A engine will run with the timing gears one tooth to the left or right of the index marks. But all is not well if that's the case. I have repaired at least three sluggish engines in the past three years in older restorations, whose fiber timing gears were ostensibly lined up properly with the steel crankshaft gear - but the crankshaft index mark had been stamped in the wrong place by one tooth! There were a ton of these inferior gears imported in the 1970's and sold almost exclusively through an unnamed Model A parts vendor in Kansas, who knowingly bought defective parts at a major discount from the national distributor who had rejected them - and then sold them at a lower price than honest vendors could. Knowing the "parsimonious" nature of many Model A owners, guess who they ordered the parts from! There are probably lots of those gears still running in Model A's, whose owners don't know what a Model A engine should run like. With mis-aligned timing gears, the engine WILL run, but it will be sluggish in performance. The index mark on the steel crankshaft gear should be located one tooth to the right of the keyway. The defective gears were marked opposite the keyway, effectively beginning the engine's life in a retarded condition that can't be overcome by advancing the distributor's cam when setting the initial ignition timing. The only fix is to move the camshaft gear one tooth counterclockwise and ignore the index mark on the steel gear. Not a lot of fun to do this, but that's the only way to overcome a defective crankshaft gear's index mark.
If Fairlane 514's engine performed satisfactorily before this misfire problem reared its ugly head, I wouldn't think mismatched timing gears are to blame.
Marshall