CONGRATULATIONS!! You have a brand new engine and it purrrrs like a kitten and it’s all shiny and bright. Here are a few pointers that come from frequently asked questions by new engine owners after we install it.
1. What is the break-in period and how do I run the engine? We normally consider 50 hrs. to be the “break-in period” on most engines. The engine really continues to “wear in” long after that, but as far as the owner/operator is concerned, 50 hrs. is it. During this time, we recommend that you avoid running the engine at high outputs for extended periods of time. If you want to give the engine a brief WOT (wide open throttle) for less than a minute, fine. It’s actually recommended to do that at least once each time the boat is used. This way you can make sure the engine will develop full speed and you can determine if anything has changed since the last time you used it. We like to have our customers “mix up” the rpms during the break-in period. This means don’t run the engine at one speed for the whole day. Every hour or so, change the engine speed, as much as practical. This changes the load on the engine and allows more complete break-in.
The first engine service, usually at 50hrs or so, is probably the most important service that your engine will have. This is where the oil and filters is changed which gets rid of all the particles of metal from the engine “wearing in”. In addition, you get remove any dirt or contaminants that might have been in the engine from the factory. Just like people under going an operation, engines get contaminated the worst from being taken apart and/or being put together.
At this point we also want to set the valve lash. Since the pushrods, rocker arms, and valves have all gotten to know each other better, they are not usually at the same setting as when they left the factory. Once we set the valves at 50 hrs., you can usually go for a couple of hundred hrs. before doing it again, but that will vary with each engine. If your 50 hr. check calls for re-torqueing the cylinder head bolts, then a valve adjustment is mandatory.
Engine alignment should also be checked at this point. The internal engine parts are not the only things that have gotten to know their neighbors better. The engine and the boat itself have figured out where they are going to be and that may not be the best thing for the propeller shaft. Engine mounts will tend to “settle” with vibration and pressure, finding where they want to be. They may allow the engine to fall lower in the boat, bringing the prop shaft out of alignment. As with the valve adjustment, once you align the engine now, you will not have to do it for several hundred hours.