Speed way below norms

[CajunRebel]

I have 2005 200 Opti on a 196 Triton. Motor seems to run perfect but 12 to 15 mph slower then the normal for this boat motor setup. Don't have a base line because I've only owned it for a short period and this is how it has performed ever since I've owned, no help from former owner. It cranks fine runs fine, does not miss at all. Has a 25" tempest prop. Water pressure seems normal, wide open trimmed up has about 14 psi, 3 food roster tail. With 2 adults and full fuel tank boat only runs 51, 52mph, and takes for ever to get on plane. Compression is within normal 120 to 130 on all cylinders when hot. Any ideas what would cause or be the problem. Also a local mechanic put new plugs in it about 6 weeks ago and gave it a clean bill of health but still never seems to preform to the norm for this setup. RPM is 4800, assuming the tack is correct. Thanks

[JOE54]

jack plate ??? engine height ???? 25 tempest use only one large hole plug 2 other holes open no plugs, 4800 way too low check throttle opening HF adjustment , git er dunn

[CajunRebel]

Yes 6" manual, 1 plug out, cav plate about 3" above bottom. I I've owned many boats very similar to this boat setup. I've had 2 20' Procrafts both with 200 Opti's. Both would run mid 60s. Also 2 206 Cobras with 200 EFIs that ran low to mid 60s. Jackplate or not, plugs out or not, rooster tail tells you motor is fairly close to the right height. Just trying to get an idea and direction for mechanic to look. Already been to one shop with no luck. Yes RPM is low but it's low because there is something not doing what it is designed to do, in other words, something is broken, not working or out of adjustment. Was hoping a mercury tech would have some idea and say check this this or this. Thanks again.

[JOE54]

bore scope cyls check for turned sleeve, reed inspection,on the water test of all sensors and switches with cds , might try 3.0L forum also for your mtr , hope this helps ya JOE

[CajunRebel]

Thanks Joe, got it ironed out today, I was assuming the boat motor was set up right from previous owner(2005��), but it wasn't, this is the first Triton I've owned. I was told(by a very experience bass boat owner)to raise the motor and see what happens, that fixed it. Raised it almost 2" which brought up the Rpms which made the motor come to life. Water pressure is 10 psi wide open. Runs about 64 65 which is about what I expected. Holeshot also decent, about normal. I lowered it a1/4" just to be on the safe side. Thanks again.

[06 SB]

The wide open water pressure is too low. IIRC, 12 is the absolute minimum, 15 is better. How long ago was the water pump changed?

[CajunRebel]

That's what it is, I dropped it a 1/4" and its 12 psi or better. It was 10 psi b4 I dropped it that last 1/4". I would rather be safe then sorry. Thanks again for the help. A bad day on the water beats a good day at work.

[JOE54]

might can send prop to my guy and gain some more, almost guarranty

[SilverFox579]

There are two, and only two, water pressure specifications, idle and WOT. Your WOT spec is below what Don advises for the 3.0 & 3.2L Optimax engines. His recommendations are minimum 1.5 - 3psi at idle and 15psi WOT. This is from the "Water Pressure 101" FAQ topic at the top of the 3L forum. There's a ton of Optimax info in that FAQ and there are a lot of smart folks that only read/respond in the 3L forum (what your engine is).