We are all entitled to our opinions and that is also what makes this website great. I was more turned off by the 350s gas guzzling. They are big, heavy, gas chuggers! Toss in the flywheel issues and that's why we looked to repower with F300's on the used Marlin we just bought. I was also a long owner of the F225s. Had the mid section issue but caught it long before it was a major repair (thanks to this website) and ended up putting almost 2,000 hours on the engines in 14 years.
Epp:
My 350's will be within a millimeter of a Marlin with 300's as far as fuel burn. They work less.
Stats:
3500-3900RPM 32-35MPH 1.3-1.4MPG
4000-4200RPM 36-38MPH 1.3MPG
The above numbers are my normal-to-hi end cruise.
Once I've burned off several hundred lbs. of fuel, I'll get 1.5 at 3500-3600 RPM. During the infrequent times I run short bursts above 4300, I stop looking at the numbers as it gives me a rash....
It's all perspective, but I don't think the 350's are guzzlers. Before Grady discontinued the 350's as an option, the performance stats on their site had the 350's equal to or slightly ahead of the 300's in the mid-range RPM spectrum.
A side note..My contact at our Grady Club never got back to me regarding the history & past ownership of your Marlin. I didn't want you to think I just forgot about your question.
I am not knocking the 300 engines. Truth be told, they are probably a safer bet than the 350's in the "Big Picture" of ownership. To me, they are the perfect match for a Marlin and I'm thrilled with them.
My selling dealer tells me Yam is considering wrangling 350 HP out of the current 300 V6 block. Ok, fine, but you will lose the unmistakable torque and incredible power that only a V8 can provide. Without the extra two cylinders, it won't be much different than the current 300 except for 2-3 MPH on the hi end. V8's rock like Eric Clapton... My Marlin planes like a RIB inflatable by just feathering the throttles. I smile every time I do it.
A final note:
1.)TUKK66:
Good luck going forward.
2.) Happy Holidays to everyone here.