Prop
Mike - Sounds like you're not getting full engine efficiency. Are you talking about .5 through the water or over the ground? What is your speed over the ground in still water? You speed through the water in currents should obviously be the same, so your ground speed should be water speed less current. Simply changing two bladed to three bladed prop isn't going to be the answer. Either you are using an incorrectly sized prop or you have an engine issue. When you run under power are you getting full revs? Over-revs? You should be proped more or less so that 80 percent throttle gives you hull speed. Check your revs, if they are high either your have too small a prop or something is slipping. If you are reving too low, either you have too big a prop, your throttle cable is not fully opening the throttlebody, or you have an engine problem where the power is low. If you get an underrev, try manually operating the throttle while someone else steers. If this solves the problem you need to adjust, lubricate or replace your throttle cable. If none of these solve the issue you need a compression check. You might want to have this done for you but I would suggest having someone do it while you watch so you learn to do it. This is a good indication of engine health. If the compression is good, next look to fuel delivery. Make sure your lines are not gunked up, kinked, or otherwise damaged and replace your fuel filters. After each step run the engine and see it the problem is resolved. Next, have someone determine that you are getting decent pressure at the injectors. The pump may be failing or your injectors may need cleaning. Only after you have ensured that your engine is in top shape should you mess with the prop. Make sure you have the correct pitch and diameter. If not, change to the correct one. If your engine is working ok and the prop seems to be right, try working with someone to move to a slightly different size to address the issue. Going to a three bladed prop is not the answer. Two to three blade switches are typically done to address power delivery characteristics, not to address power deficiency. A three blade prop will need to be of small pitch or diameter than a two bladed prop so that the load on the engine remains appropriate. You will get more water pushed with the three, good for close quarters and docking manuevers, but you may lose top end. Justin - O'day Owners' Web
