Poor Hole Shot and only 4200 rpms. Advice?

[Borkman]

BMCD, correct, I have no jack plate. I do have a set-back bracket. My motor is mounted 10" back from the transom. My back bracket is not adjustable.

If it were the tach being off, even if it only showed 4700 rpms, shouldn't I be getting a bit more than 52 mph gps? Others have seen 60's with this boat and motor.

Only thing I can think of is perhaps I'm not trimmed up as far as I need to go. You said WOT and trimmed all the way up. I can't say that I've done that. I just don't know. Again, going back to the start, this is my first ever bass boat. The hot foot is buried to the floor, but I don't know where the sweet spot should be for the trim. I can take her out next week on a calm evening, run down to Lake Superior where I have a lot of real estate, and bury it again when I have enough real estate to really play with the trim.


Otherwise, my plan now is to run over to Brainerd (bass country) and test drive 23 and 24 pitch props. None of the shops up here have those props to demo. If I can get the rpms up a bit, and not take anything off the top end, I'll purchase a new prop. Otherwise, I think I'll invest in a jack plate. I have a buddy with an engine hoist. I've watched a few videos on it. I think it should be straightforward to just install one myself with a few buddies and a few 6-packs to get them there. Unless I'm being very naive here. .. . . local shop wanted $600 for install of a manual jackplate, plus the $400 for the plate itself.

Stay tuned, it may be a week or more before I'm able to test drive some props.

Again, thank you for your time and input . . . Borkman

[Chainslinger1959]

Thanks gents,

I'll call the local Merc dealer on Monday. My guess is they may be two weeks out on appointments. I'll also have them make sure the injectors and power packs all check out. That's what someone else suggested to me here in MN.

However, I'm accustomed to my work boats (I'm a fish biologist here in MN) and I really don't think my Merc is into the 5000 range. A 2-stroke running 5000+ rpms should be much louder than my motor is, at least that is what I'd suspect. Maybe I'm wrong, but the old 2-stroke Merc 50 on my electrofishing boat would just scream WOT.

However, that being said, on the Nitro Set Up thread on this site, most other 901 CDX owners were running the same Tempest Plus 25. I've called around to all of the Duluth / Superior Merc dealers, and no one up here has demo props for this boat. Everything up here centers on walleyes, and Lund is king. A Nitro dealer in Missouri that I called on Friday suggested perhaps a Tempest 23 or a Fury-4 24. Those are non-existent in the demo world here.

I think I'll take the motor in for an inspection. Never considered that the tach may be giving me faulty numbers. I'll just ensure that everything is purring as it should. Then maybe I'll call down to the Twin Cities and see if any of the Tracker dealers down there have demo props for me to test drive.

Now, I'll go out and yank out those PVS plugs and see what happens tomorrow on the lake . . . Thank you!

Borkman

I owned a 2003 901 cdx 200 3.0 litre merc number one 24 tempest two large pvs plugs the other hole no plug.
Boat should have at least a adjustable jack plate mine was hydraulic. I think your engine is to low or at least sounds like it.
Mine had a 10 inch setback . It is a heavy hull but mine ran 65 and sometimes 68 loaded heavy.
Maybe some kinda throttle issue .

[Chainslinger1959]

BMCD,

Can you fill me in on what you mean by getting good lift? I don't know what bow lift is all about, or what is good, bad or otherwise. When I stomp on the hot foot, the bow raises, then drops down when she gets on plane. When I trim her up, last night to 4700 rpms, I didn't really notice the bow lifting at all. I did notice the splash created by the hull moving further back past me and towards the transom.

thanks!

Not trying to be a smart ass but is speed gps or speedometer on dash?
J. D

[Borkman]

gps speed

[Chainslinger1959]

A 24 is perfect for that boat my opti 200 had a lot of torque. Motor may have a problem or boat may have a hook in hull.
I never saw a 9 series with a setback plate that was fixed that’s a new one on me.
My boat always ran consistently 65 had no issues as yours does.
J. D.

[Borkman]

thanks Chainslinger.... Motor did check out perfectly (see above). My intentions are to try to find a Merc dealer with a 24 that I can demo. Those don't exist here in Duluth, it's Lund country and not Nitro country.

I swear, my setback plate is not adjustable. I've had 2 others evaluate it. It's frustrating. Thanks - Borkman

[Fishysam]

thanks Chainslinger.... Motor did check out perfectly (see above). My intentions are to try to find a Merc dealer with a 24 that I can demo. Those don't exist here in Duluth, it's Lund country and not Nitro country.

I swear, my setback plate is not adjustable. I've had 2 others evaluate it. It's frustrating. Thanks - Borkman

You can post pictures of the set back plate or text them to someone like me.

You should be able to trim it all the way the way up to the end of the trim rams, the tilt ram is not strong enough to lift it higher. Do not hit boat waves at 50+mph with it trimmed all the way up. M

my boat will only go 50 mph at full throttle if I do not trim it up, the more up the faster as it lifts the front of the boat out of the water.

[Borkman]

Images of the back plate are attached. There are bolts running thru the rails, all the way thru with lock nuts on the inside. There's no threaded rod at the top that can be manually turned to raise or lower the motor. There's only the motor mount holes. If you still want me to, I can take an image of the top looking down, so that you can clearly see it's an empty shell. There's nothing there. It's not a jack plate. Oh how I wish it were. Perhaps some of my problems would be easily fixed.

Per my response to BMCD, I'm not sure I've been running it tilted to it's sweet spot. I'm still learning, this is my first bass boat. Next time I go out, I'll be a little more intentional with playing with the trim. Maybe my issues just come down to not trimming it enough. That would be sweet!

thanks all!

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[Sun Fish]

Keep trimming up after you have it floored if you have a clear path until it starts to get squirrelly if ever. You cant trim into the tilt range when running if you werent aware, it wont allow it.

[Borkman]

Sunfish, I was not aware of that. I've got a lot to learn! Thank you!

[BMCD]

You can only go so high, once your out of the range of trim it will not go up anymore. Just hit that up button.

[Borkman]