I have a 1999 7.4 MPI Mercruis
I have a 1999 7.4 MPI Mercruiser IO. The SELOC manual states I should use NGK BPR6EFS spark plugs. The plug I pulled out was an AC MR43LTS. The replacement plug I was planning to use is a Champion RV12YC. The difference in these plugs is the reach - .406 vs. .708. Does that matter?
I have a 1999 7.4 MPI Mercruiser IO. The SELOC manual states I should use NGK BPR6EFS spark plugs. The plug I pulled out was an AC MR43LTS. The replacement plug I was planning to use is a Champion RV12YC. The difference in these plugs is the reach - .406 vs. .708. Does that matter?