Posted by Sherman in Idaho [24.32.202.166] on Monday, August 26, 2013 at 20:27:22 :
In Reply to: M37 sputtering posted by Levi [68.246.86.19] on Monday, August 26, 2013 at 20:08:47 :
Clear inline fuel filters tend to never have much gas in them unless you make a real effort to get the air out. If I understand you right, it sounds like it's sputtering more when lugged down than at higher RPMs, even though the road speed is identical. To me, that points more toward a spark issue than a fuel issue. Of course with a spark issue, there are all the usual suspects, but you might at least start with a good visual inspection of the plugs, plug wires, distributor cap and rotor, coil, etc. Some guys have had success looking at a running motor in the dark, to see the corona discharge across dirty wires or other places that are not insulating as well as they should.
A fuel starvation issue will usually show up worst when the throttle is wide open and you're running at high RPMs, like climbing a long hill that's too steep to go up as fast as you'd like.