Gas and Oil Home Heating Furnaces - burners won't ignite on Nat gas furnace

Have a nat gas fired boiler with intermittent pilot (spark) ignition system. Igniter provides a continuous spark when tstat is raised but pilot does not ignite. When I insert a long match near igniter, the pilot lights then the main burners follow. Also, when I blow in the direction of the igniter it also lights. When the pilot lights, the mains kick on everytime so guessing the sensor is ok. The igniter spark is well defined and continuous and I'm guessing hot enough. I haven't yet removed the burner tube the igniter is attached to but am I correct in assuming the distance between the igniter and pilot gas tube is fixed? If not fixed could they be adjusted to move the spark closer to the gas? Or does it sound more like a clog/obstruction of the pilot gas tube?

Thanks

You asked so many right questions that I would not be surprised that I am now talking to myself, and you already have it fixed. Yes, I would make sure the pilot orifice is absolutely clear as it can be as it just might be to the point that even though a lighter gets the gas going, that the gas is coming out slower and possibly wafting away from the spark.

Thanks for the reply. Figured it didn't hurt to ask you guys as you know best! Actually did remove the pilot/igniter assembly and gave all a cleaning, that seemed to do the trick. Also, the unit seemed to light up quicker when the cover that encloses the burner tubes was put back in place. Guess it improved the pilot gas concentration. Thanks again!