21' Maxum Cuddy Cabin questions???? - Maxum Boat Owners Club

fishin1789 · 09-14-2009, 01:44 AM

I have a 1992 21' Maxum 2100LDC with the dreaded Force 120hp L-drive. I just bought this boat and it doesn't seem to get on plane correctly. It has a 13X16 3-blade aluminum prop and takes 7-10 seconds to get on plane. It is turning about 4400rpm at WOT while on plane. When coming out of the hole it is straining hard to get up to 3500rpm. It also has some porpoise issues while running, even with the drive trimmed all the way down. Any ideas if this is the correct prop? Will a "fin" help? Is this the correct WOT rpm? Any help is appreciated!

seapuppy · 09-14-2009, 02:28 AM

Fishin
welcome to the zoo....although you have a small boat....your wot rpm is at the low side of the acceptable range..but it's there...I'd look at changing the prop to a 14x16 pitched prop....go to your local prop shop and they are sometimes willing to let you try a few props with a down or credit card hold and then charge you only for the prop you buy....

as for the trim wing...I don't think I'd do that myself..I'm not a fan of those and there are some that say it isn't worth the money while others will say they work....one of our other members will hopefully chime in and offer some experience...

what I think I'd really do is install those auto trim tabs....they are spring loaded and will probably work better than those wings you attach to your drive...

SP :hello:

Gazjen · 09-14-2009, 12:11 PM

I had hydrofoils on my 1900 SR they did work but they must put a lot of strain on the drive more suited to smaller boats I think, now I have smart tabs on it. they are cheap, easy to fit and work well

racer2c · 09-14-2009, 03:00 PM

Sounds under powered to me. I'd try the 14x16 that seapuppy recommended and trim tabs, I'd go with electric or hydraulic though so you can force them down as needed coming out of the hole. I'm just finishing up installing hydraulic tabs from Bennett myself, fun little project for a DIY'er.

Gazjen · 09-14-2009, 06:20 PM

There's no need to go to the extra expense of hydraulic tabs the smart tabs work fine and can be adjusted for down force as required

racer2c · 09-14-2009, 06:28 PM

Quote:

Originally Posted by Gazjen

There's no need to go to the extra expense of hydraulic tabs the smart tabs work fine and can be adjusted for down force as required

Depends on the issue one hopes to resolve by installing a trim tabs. In my case I chose hydraulics for the control to correct list caused by passenger placement, a huge issue with a small boat like mine. If the issue is solely for getting on plane faster, everything I've read about smart tabs, they are a simple, affordable solution. But the bottom line is there are "reasons" for going with controllable trim tabs.

Gazjen · 09-15-2009, 07:56 AM

But he wants to get on the plane quicker so therefore smart tabs

racer2c · 09-15-2009, 09:33 PM

Quote:

Originally Posted by Gazjen

But he wants to get on the plane quicker so therefore smart tabs

Well, there you have it. I'm sure he appreciates you choosing for him.

Dave · 09-15-2009, 11:45 PM

Now-Now boys... Play nice...