2006 Baja 202 Islander prop

[dlogvine]

I almost finished restoring a 2006 Baja 202 Islander. It has now 1993 5.0L v8 Mercruiser engine, just rebuilt, with .30 over bore and Alpha one gen 2 1:1.64 outdrive. The boat is about 22ft or 23ft with the swim platform. Weight is about 3000lbs, maybe a little more with extra battery, anchors and other equipment onboard. The propeller is 14×19 aluminum.Took it to the lake last week and the boat was going around 25mph on the half throttle. The RPMs at this setting were around 3000. When I gave WOT, the RPMs did not change, neither did the speed. I had some problems with the trim settings, the gauge was not showing much. But when I was tweaking the trim, I managed to get RPMs to 3500 and speed up to 30mph. I'm going to change the prop to SS 14×17 and try to play with the trim more.
My question is what would be a standard prop for this setting? I'm not looking for super fast boat, never go over 35-40mph on my other boat and most I really need is 25mph when water skiing.
thank you.

 

[QBhoy]

Hi.

By what you have said above, you have other issues. The prop would not cause this issue. To see no increase in speed or Rpm’s going from half throttle up full throttle means something else is going on.

 

[Scott Danforth]

you have an issue.

your motor should be spinning that 14x19 aluminum prop right to redline.

so go back to the motor. take a look at the carb. look at the plugs to make sure they are all firing, do a compression test.

my 2002 SeaRay had a 5.0/Alpha with a stainless Solas 15x19 and pushed the boat just shy of 50 with WOT at the upper range.

 

[dlogvine]

The motor is recently rebuild and it starts with a half turn of the key. Compression was checked when we just assembled the engine. It was running at close to 160psi in all 8 cylinders. That is one of the first tests we did to see how well did the shop bored the block. The engine itself is running very smoothly with a brand new spark plugs , wires and distributor. Carburetor was also rebuilt. Outdrive was also checked before installation, gearlube changed, new impeller, we checked the gears and bearings. So it all runs fine. There are no rough patches in the running, no grinding noises. I'll take the boat to the lake tomorrow and record a video of the run.

 

[jimmbo]

When you rebuilt the Engine, what Camshaft was selected?

 

[dlogvine]

Camshaft came with the rebuild kit. It is a marine camshaft for sure. Old one had some lobes worn pretty badly. The kit was purchased at the machine shop, so I doubt the guy who sold it would have given a car camshaft with a marine kit.

 

[jimmbo]

What Carb is on it?
Have you verified that the Spark Advance is working?
Does that Engine have the Backflow shutters in the Exhaust Pipes?

 

[dlogvine]

Backflow shutters are in, from original 2006 Baja Islander. Carburator is the original 4 barrel either Mercarb or 4 barrel Rochester. I'm pretty sure carb is working fine since the engine is running very smoothly, no noises. Same could be said about the distributor. By the way the engine starts and runs I don't think there is any problems with ignition and timing.
Ill play with the engine in the water tomorrow or Wednesday.
One setback, my daughter and her boyfriend just burned the engine on the jetski.... damn. Will have to take this sucker apart to see how extensive is the damage.

 

[jimmbo]

Kids...

 

[dlogvine]

Crap the engine is fried. I did not realize at first that the original color of a head cover was green and not black. So was the color of an exhaust elbow. My friend who owns the jetski rentals and repair looked at this and told me that he had never seen anything this fried. Looks like they banked the vessel on the sand and started it also while sitting on the sand with full intake of sand. This sand went through everything, clogging the water cooling system. Dumb teenagers. Looks like it will be at least $500-700 repair. The whole top end must be rebuilt and probably ill need a new head cover or if it is not too warped ill need it milled. On the top of it, came home and AC is blowing hot air. WTF is wrong with everything?