2400 SCR engine upgrade - Maxum Boat Owners Club

Mike Carmine · 01-13-2012, 07:27 PM

I have a 5.0l basic 8 cylinder (305ci Ford engine) in my 2400 scr. I am adding a swim platform and now worried that the boat will not plan. When it is time to overhaul the engine which will be 2-3 years is it cost effective to just drop a 5.7l in the back with an Alpha drive? Or would a new bravo drive deliver more thrust? I have had the boat for 1 season.

biggerseagar · 01-13-2012, 08:26 PM

Mike you ask good questions. Some of these answers might be........... what is your checkbook like nowadays? Want to drain it? How handy are you? Are you going to do all the work yourself ? You must have an older Maxum if you have a ford engine in it. Are you sure it is not a 5.0L chevy?

If it were me I would look for a new boat. You will sink alot of cash into this old boat with what you are talking about and it will be for your enjoyment because it won't increase the value at all. But that is me..........and hopefully you have a reason to do all this to your boat. A simple overhaul to do this yourself on a 5.0L chevy is nothing. To change your outdrive you better know what your doing$$$$$.

All this because of a swim platform? Is this homemade or ordering from a manufacturer? Do you have trim tabs? That would help you get up on plan and alot cheaper than all this other stuff you want to do.

Well that is my 2cents worth........you got the winter to think about all this. B.O.A.T> Break Out Another Thousand!

Have fun

Roger

GlennW · 01-14-2012, 12:23 AM

As mentioned above the swim platform is not going to hinder the perfromance of your boat. Most people hear 5.0 and automatically associate it with Ford's 5.0 Mustang. You most likely have a 5.0 305 Chevy.

As mentioned above, if you replace engine and drive with new using a dealer you will spend about 12-15 thousand dollars, most likely more than you have a budget for.

In a couple years if you have motor problems it may only need a top end redone which is fairly easy and can be done in a day if you are mechanically inclined.

A long block is also an option if you can install, but go with a direct replacement and leave the drive alone.

Mike Carmine · 01-14-2012, 02:56 PM

Yes it is the Chevy 305. I will take all your advise and leave it alone and just add the swim platform and not worry about with this boat.

seapuppy · 01-14-2012, 04:05 PM

you have to look at something here....the ctr of gravity for the boat is just in front of the engine....so..as the pivot point for the added weight is aft ..it's going to help in the lift of the bow.....but in reality it's a minimal addition of weight......
yes you have a chevie engine 305 cu in....220 hp....carbed....with an alpha one drive....what yr is the boat??...
as mentioned...there are alot of folks that add that platform and it gives more room on the stern to chill and enjoy.....just make sure you have all holes drilled into the transom sealed.......

oh yeah..welcome to the zoo..

SP

ss3964spd · 01-14-2012, 05:04 PM

If you do indeed need to re-power the boat at some point then using a 5.7L in place of the 5.0 is a no-brainer, and the Alpha drive should be up to the task (they did hang Alpha drives behind 5.7's, didn't they?).

A 5.7 long block will be only slightly more expensive than a 5.0, and both are the same cost to rebuild. The 5.7, regardless of it's HP rating, will produce much more torque than the 5.0 and torque is what you need to get that boat up on plane.

Cost/benefit analysis is straight forward. How much could you reasonably expect to sell the current boat for vs. how much would it cost to replace it with something comparable but newer and with more power? The difference betwen those two numbers will tell the story.

Mike Carmine · 01-14-2012, 06:32 PM

...what yr is the boat??...

The boat is a 2001 now with 220 hours. I replaced both dashes, the 12v dc fuse box below the instrument panel. I killed one battery by never charging it because the book says never run on both batteries so I never charged it all summer and then wondered why all my electronics started to fail. Classic Newbie. I am putting AGM batteries in April. I would love to relocate that battery switch to make it easier. I replaced the electronic ignition module and insulated it from the riser which killed it. Any other known problems I should look out for. The boat is a salt water cooled engine which to me is just crazy.

cj · 01-14-2012, 11:12 PM

Hello all, i have a 97 2400scr with an extended swim platform, 5.7lx alpha1 running a 19pitch high five prop...pics r in the gallery... I found the boat to be very sensitive to trim and porpoising prior to me installing the platform, as most boats like this are, and given the fact that the platform weighted probably 300lbs, i was weary of what it would do to performance as-well. It has been three seasons since I installed it and absolutely love it. The only issue with it I had found is that I was unable to trim the boat at any speed without it porpoising, most likely from the added weight aft, and even with the trim all the way "in" the boat would start porpoising at about 25mph. I was able the stop it by running a little tab, but at the expense of mph. I finally tried one of those fins that you install on the leg and it totally cured all the porpoising issues that I had. I am now able to run the boat at any speed/trim setting without any porpoising issues. I am able to load the boat up for a weekend camping trip with the wife and two kids and still pull them on the tube along the way with the 19pitch highfive and still top out at about 39mph (gps).....all in all i cant complain......just my 2cents....cheers
chris

GlennW · 01-15-2012, 12:58 AM

CJ,
I'm a firm believer in the Stingray type tabs that install on the legs (drives). I have run twin and triple 525HP's that did not need them but also have run 19'ers with a 4.3 that it helped out tremendously with. Porpoising is really a pain since it only happens at wake speed with single drives.
I've slowed down now to a cruiser, but.....you never know for how long!

cj · 01-15-2012, 02:17 AM

....ah yes, stingray... that is the fin i installed. I too am a believer. I know there is a lot of negative talk about them, but my last boat (caravelle) had a stingray tab as well and had 700+hrs on it when i sold it and never had any adverse problems with the drive, other than changing out u joints, gimble bearing, bellows & oil etc...the usual stuff.....everything else was tight.....and it made that boat ride great as well....cheers
chris

biggerseagar · 01-15-2012, 07:18 PM

You will get better trim adjustment out of adding trim tabs to your boat than the whaletale stuff.

Roger

cj · 01-16-2012, 10:35 PM

....agreed, but we already have tabs, and the amount of negative/down tab needed to stop the porpoising resulted in stuffing the nose way in and losing a great deal of speed/range and ride. With the Stingray you can trim up all the way resulting in a much greater "usable" trim range with out any porpoising at all....better ride...better speed...better fuel....
cheers
chris

biggerseagar · 01-16-2012, 11:19 PM

Well in that case try one. I had a tail on my Bayliner 2655 and it did a great job, but also had trim tabs. Came with the boat.

Sometimes just shifting some weight around that is inside your boat can help.

If your porpoising alot you have trimmed up too much. Your wash should be right behind you in the driver seat. Some boats just don't need alot of trim. Good way to spin a prop too.

Roger