Marine Kinetics vs Crane for longevity?
#1
Good Morning OSO!
I have a 42 Sport Fish powered by twin 502’s and Arneson’s. This boat lives between 3,500 and 3,800 RPMs 99 percent of it’s life depending on how it’s loaded. Motors were gone thru and updated about 400 hours ago, and I think it is time for valve springs at least.
I am also concerned about cam and lifters. Here’s why:
I purchased cam, lifters, and AFR heads from Marine Kinetics based on the recommendations from many on this site. After about 100 hours, a lifter decided to fail ruining the cam, and chucking the engine full of metal. I reached out to Bob at Marine Kinetics, and he promptly blamed a weak spring as the culprit. Bob sent me new cam, lifters, and springs (on my nickel, full price) and boat has been trouble free since then. Just to be fair, the engines have run beautifully. Smooth and powerful!
Since then, Marine Kinetics seems to have fallen out of favor on OSO because his cam philosophy has caused issues for many? Failed lifters? The boat is used offshore in the PNW and Canada, and it must be safe. (dependable)
My question to you all, is should I replace Marine Kinetics custom ground cam with something off the shelf? The closest one is Crane’s 168731. Should I expect more than 4 or 5 hundred hours from Cran’s vs MK?
Has anyone gotten 1,000 hours out of either?
Any advice or ideas would be greatly appreciated.
Thank You,
Steve
I have a 42 Sport Fish powered by twin 502’s and Arneson’s. This boat lives between 3,500 and 3,800 RPMs 99 percent of it’s life depending on how it’s loaded. Motors were gone thru and updated about 400 hours ago, and I think it is time for valve springs at least.
I am also concerned about cam and lifters. Here’s why:
I purchased cam, lifters, and AFR heads from Marine Kinetics based on the recommendations from many on this site. After about 100 hours, a lifter decided to fail ruining the cam, and chucking the engine full of metal. I reached out to Bob at Marine Kinetics, and he promptly blamed a weak spring as the culprit. Bob sent me new cam, lifters, and springs (on my nickel, full price) and boat has been trouble free since then. Just to be fair, the engines have run beautifully. Smooth and powerful!
Since then, Marine Kinetics seems to have fallen out of favor on OSO because his cam philosophy has caused issues for many? Failed lifters? The boat is used offshore in the PNW and Canada, and it must be safe. (dependable)
My question to you all, is should I replace Marine Kinetics custom ground cam with something off the shelf? The closest one is Crane’s 168731. Should I expect more than 4 or 5 hundred hours from Cran’s vs MK?
Has anyone gotten 1,000 hours out of either?
Any advice or ideas would be greatly appreciated.
Thank You,
Steve




