I have a rude 78 model 140 hp the book recomends a UL77V spark plug but my local dealer said he does not stock them but he recomended the QL77JC4 , just wondering if there is any reason why I should not try and use this type of plug on my motor.
The QL77JC4 would be my first choice for that motor on todays fuel. Especially if it's not set up at the upper end of the rpm range. Just make sure to use only 87 octane.
