Do make sure they are propped properly. Depending on model, I think those are 2600RPM engines. On the sea trial, pin the power levers. You should see AT LEAST 2600RPM and preferably 2700+. If it is less then it is overpropped. And then you have decisions to make...ref how many hours...when was the last time the prop pitch was changed....etc. My point being if it can only reach 2300RPM and there is 1500 hours on the engines, they might be at the end of their life if they have been run hard under those conditions. Other than that, Seaboard has all the info you need. Good luck!!! Great engines!