Hi guys, finally solved My problem with engine not Revving out past 3200Rpm.
Hope this helps someone else out there with a similar experience.
A Wrong Prop recommendation by a Marine mechanic has cost me several hundreds of dollars and many lost hours chasing this problem.
Luckily, I'm pretty good on the tools and have a bit knowledge so I have saved a packet on man hours / Labour.
Summary:
Bayliner 245, 2004 Model
Engine: Mercruiser 5.0L Carby
G/box: Alpha One leg 1.62 Ratio
Prop: 15" Dia x 16" Pitch 4 Blade
Top speed: 60km @ 4700Rpm W.O.T
So, boat ran fine since purchasing it. Had been out on it approx 5 or 6 Times.
Problem started when I bottomed out on the sand which in turn stalled engine.
Engine stalled because I was in gear idling, revs where down / low so it killed the engine.
Bent 2 blades slightly which then caused a vibration.
After a while went to accelerate, boat wouldn't rev past 3200Rpm.
Step 1:
Purchased a new prop from a marine shop, mechanic recommended the Black Max 3 Blade 14 1/2" Dia x 19" Pitch.
Told me it would give me a couple more Kms Top speed & better fuel economy.
Later that week I put new prop on and went out to test it.
Boat still wouldn't rev past 3200Rpm with new prop.
Step 2:
Carried out the following repairs & checks as per my Post #30
The only additional things I done since that post was,
Check intank fuel pickup screen
Removed rear leg to check exhaust for 1/2 missing exhaust flapper.
Step 3:
Returned boat to water today with another prop which i borrowed off a mate, Quick Silver 3 Blade 15" Dia x17" Pitch
Boat instantly revved out to 3800Rpm W.O.T which was 600 Rpm more than last time out, then approx 10 seconds later it started getting on the plane with a top speed of 62km @ 4900Rpm.
Full tank of fuel and full tank of water with 2 people on board.
The engine purred along at that speed for about 5 mins and it felt great.
My Conclusion
Simply the 19" Pitch is not suited for a 5.0L Mercruiser in a boat like mine.
With that 19" pitch it just couldn't reach that optimum Rpm to get it any where near up and over that hill to start planing. That extra 600 Rpm more was what it needed to get it there.
My opinion of that pitch is that it may be more suited to a 5.7L with a bit more power.
Don't know how to post up a video of it ,,,,
Big thanks to all you guys that responded to my thread and helped me along the way with your expertise & Knowledge.
My next issue is, what prop should I put on as I'm intending to put a swim platform on which will add another 80 to 100kg.