I repowering a 1975 Sea Ray 20 ft. SRV 200 I/O. I'm replacing an OMC 235 (Ford 351 V8) engine. Should I select a marine or truck engine?
I searched the internet (Google) to find an answer, but after receiving conflicting information about the differences in truck and marine engines, I'm more confused than ever.I understand the differences in the performance demands of car, truck and marine engines, but are there really differences between remanufactured truck and marine engines?I use my boat for pleasure, about 10-20 times per year, about 2 hours each time. We tow skiers, tubes, rafts and joy ride.Your article (Boating Mag, Feb. 2010, page 22) didn't really speak to the differences and the benefit of a marine engine over a truck engine.Can you help enlighten me?ThanksDon
After asking myself the same question over and over again, it is my conclusion that your best bet is to install a rebuilt MARINE engine. Biggest reason is it is designed for just that purpose, a demanding and harsh wet enviroment were it runs a constant 4000 - 6000 rpms verses an auto engine that rarely ever sees over 4000.
I've seen more than 1 person become very dissappointed after installing other than a proper marine engine as a replacement, as automotive type engines including light truck engines generally have diferrent cylinder heads and camshafts due to emmission restrictions, and do not produce as much power as a proper marine engine. The blocks are generally the same however, and most of the marinized parts on the marine version can be easily changed over....but it's worth the extra few bucks to buy the right engine...
What the guys above said. Since a boat doesnt have a multispeed transmission, the engine is always revving high RPM, thus the mapping is different. And the bolt-ons, like starter motors, alternators, etc are rated for the environment and safer in closed engine rooms, versus the "open to the air" environment of a truck.
I think a Marine engine is the best choice. It's important to use marine parts such as starters, alternators and such, otherwise you might find the engine removed from the boat in an unexpected manner. I wonder if marine ignition protected parts would mate up to a non-marine engine?
Check the re-builders reputation carefully. If someone else is purchasing and installing the engine, I think it's still wise to check the re-builder. I was looking at U.S. Engines until I read feedback from other people, and learned the company has several outstanding, unpaid judgments from unhappy consumers.
I also found out having a high BBB rating doesn't mean as much as I thought. For example, US Engines BBB rating has varied between a D and A+ over time, since BBB excludes complaints that result in judgments. In other words, you file a complaint with the BBB against a business, and the BBB business rating is dragged down. However, if you file in small claims (or other court) and win, with a judgment in your favor, BBB removes your complaint from the rating process for that business.
In my opinion, marine engines are the safest and best way to go!