I am continiously fouling the recommended QL16V or L16V Surface Gap Spark plugs. Can I sub these plugs with another Gap type. I am using hi-grade oil with 50:1 ratio mixture. Note: Lake water temp is 50F or lower.
The commercials specified the surface gap plug more often than not. I think this is supposed to be from a maintenance standpoint and not an interference issue. The non-commercial versions of that motor use the QL77JC4 gapped to .030. Hopefully someone who has seen your exact motor can tell you if it is safe. The heat range should be fine - just need to make sure you have piston clearance.
Heh. Should resolve it if you've got a fouling issue but keep an eye on them. I posted a very opposite thread, as my old Merc's ran wonderfully on them and they're specified as an alternate plug for my 25hp Johnson - but the answers came fast and furious. "Don't even bother" was the general tone.