trying to get the right prop set up

[Ghost Rider 2]

I was directed here from general boat questions. I have a 1972 Winner wildcat 18' closed bow. Had a 135 Chrysler that lost a cylinder. Replaced with 140 inline 6 Mercury. Boat is not acting right, seems to have lost its balance. With the Chrysler boat would plane and run very smoth at all speeds. With the Mercury it porpusses at anything below 4750. Also has trouble getting a skier up. With th Chrysler 1 person 5200rpm max 42 mph 2 or 3 people 36 mph. With Mercury 1 person 5500 rpm 50 mph plus 2 or 3 people 45 mph. Boat is faster on top end but not much power coming up. Also it has a ton of water spray at the transom. Trimmed down it will roll up in the well. Trimmed up instant porpus. Prop on Mercury is a 13X19 prop on Chrysler is a 13X17. The boat runs great if you keep it above 5000. But stuggles at lower speeds. My wife is not happy with this boat right now, looking for help on prop selection. Top speed is not a main concern just to pull skiers and towable tubes. Thanks.

 

[Crownie2]

Re: trying to get the right prop set up

Sounds like it could be mounted too low.

Where is the anticavitation plate in relation to the boat bottom? Should be slightly higher than the bottom.

Do you have power trim? Are you using it?

Bob