In a Volvo 4.3 penta engine I just pulled the plugs to change them they had RT43 AC plugs gapped at .035 are these plugs ok to use or should I go with Volvo plugs the engine seem to run finne all last season on the old ones.Thanks
Your motor is running fine with what you have, but just in case you want to know what merCruiser service bulletin No. 97-17 list for oem, it would be AC-MR43T if they are short reach plugs and AC-MR43LTS is they are long reach plugs. However, if "run on" ever becomes a problem that same service bulletin recommends the cooler plugs of AC-MR41T for short reach and NGK-TR6 or Chapion-RS9YC long Reach.