I went to lordco and asked if they had marine spark plugs to replace mine I brought my old plug in went home to install it not even looking at the new plugs. I put the first 5 in no problem on the 6th plug I had to remove the 5th plug to get at it..when I took out the new plug I noticed the end was bent theres no possible way these could fit in unless I only threaded them in 3 threads not even a 1/4 of the way...take em back i guess??