Jim; It sounds like your not quite certain if its an ignition or a fuel problem...but if it ran before you replaced the timing gear, its more likely that something is amiss there...

Some questions to the symptoms:

Are there ANY sign of ignition or does it just crank and crank and crank? (No spark...which you said you did have...the question is spark happening at the right time, and what is it trying to ignite!...pull a plug...is it soaked?...dry plugs, retry).

Does it spit back through the carbs and generally sound like it's going to blow up? (Ign wires on the wrong places, or timing gears missaligned...did you align the marks or dots on both the new timing gear and the smaller crank gear? If your certain you did, then the important thing is OK, and it's more likely that there is something amiss with the ignition.

Did you adjust distributor(timimg) after gear replacement work? (double check timing, either static * or with a t-light).

* See ignition info at Service Notes page: http://www.intelab.com/swem/Volvo%20Ignition%20from%20Scratch.htm

Please let us know what you find.

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