Badly fouled props will cut your thrust. The heavier the fouling, the worse it gets. I'll refrain from the dipstick question, only because I have a Sundancer, with v drives and you have straight trannys. This photo is immediately after hauling out for the season on 10/15. I launched 5/23 and, had no reduction in power. If you've got hard fouling, especially on and around the hub, it can be like using a prop half size, or worse, and well, these old girls have got some big old bums to get up and move! You'll need full props.