MV 2272, S/C Ecotec 2.4L, Scott 752

[Maxxi]

FWIW  I have a 2.4 ecotec  750 scott.  The boat is on this forum  JBM(Dick)   March 2011.   The boat was a night mare and took me three years to make it run properly.   I should have built it myself as I have had to gut the boat and rebuild ALL basic installs from gas tank mounts to seat mounts to foam in floor, pump issues and ENDLESS engine issues.  I dont even want to talk about it.   

That said I have a few questions and comments.

First...  the jet you will love.   Even though Dumb A. installed the pump so as it leaked bad at the transom and a little on the intake the pump itself has been fantastic.  ONly wish I had the 752.

Although it took  three wiring harnesses not one of which was built properly to get one that actually worked  once I did the motor rocks.   About 200 hp.  (one 19 pitch rpm 6000 arguably i need a new impeller now that I have the engine making power.) The harness is from CBM  but I tell you right now they are NOT BUILDING  them like they say they are.   Second mine was NOT BENCH TESTED.  It simply did not work when it showed up and it took days again to trouble shoot the harness.   Four wires were wrong and had it been bench tested it would be obvious instantly.


I did a lot of reading and calling re computers and I do not understand how you are going to program that computer to fit your motor.    In fact it was my understanding that the mefi 5  or any computer that looks like the one you have is not changeable with out the proprietary software.   maybe this has changed...? 
I thought the whole idea of buying a harness and computer was that the programming would be done already?   Other wise you are just buying some wires.

I am just talkin here.   There is no right way.

A day late and 100 bucks short I sure would have suggested you go with the 752 / 2.4 NON super charged.     
With the charger you must run premium and engine temps under hood temps are high.     To be honest I have never heard of or seen a 2.4  supered....  2.2 yes...  not 2.4.      In my opinion the extra power is almost not usable because you can not sustain the load  for the heat that is generated.   For something like a sprint boat or anything where you can limit duty cycle what you have made would be outstanding.     You may not realize that once you go over 4000 rpm with that motor your fuel consumption is going through the roof.   It will sure be fast but I do not know how practical.


Perhaps this is all just fun for you and problem solving all this is what you seek.?



Im not sure how you are going to reduce the boost but I guess you have thought of that.  (pulley size but what size)  The base motor will have too high of compression to boost until you get up to at least 3000 rpm.  Thats a guess.
That super charger is also noisy as hell.  No really it is.   I have talked to two guys that owned 2.2 supers and at first.... lots of fun... two hours up the river....  holy crap does this thing burn fuel and it is sure  loud...   " I SAID...  WHAT"  i CANT HEAR YOU.

At the very least you have a perfect motor and pump combo.  I mean perfect.   If you decide for what ever reason you can pull charger off and go back to NA.  You will need new impellers and a different computer program  but thats not too big of deal given how far into the boat you are going to be.

Oh and one last question as my exhaust  manifolds have design flaws and I might have to order a new one what did that manifold and riser cost.
mine is made here in North America but then  was discontinued as there is no market because Marine engine department in Louisiana stopped making  2.4 marinised motors.    The casting is really crap not to mention mine leaks at the riser.     I am sure I can grind these one and use different hardware to make them work better but depending on cost .....

well cheers.   

 

[AKLiving]

FWIW  I have a 2.4 ecotec  750 scott.  The boat is on this forum  JBM(Dick)   March 2011.   The boat was a night mare and took me three years to make it run properly.   I should have built it myself as I have had to gut the boat and rebuild ALL basic installs from gas tank mounts to seat mounts to foam in floor, pump issues and ENDLESS engine issues.  I dont even want to talk about it.   

That said I have a few questions and comments.

First...  the jet you will love.   Even though Dumb A. installed the pump so as it leaked bad at the transom and a little on the intake the pump itself has been fantastic.  ONly wish I had the 752.
...

I'm sorry you had such trouble.


While I won't know if there are any problems with my harness until I'm ready to tune it was reassuring that Steve called me the other day just to see how it was going. I'm sure he can make mistakes but it's good to know he cares about what he sells. I don't remember the last time I got a call from a business like that.


As for the 2.4 LE5 supercharged - there are a lot of them out there. Most still in cars and many in rock buggies or similar. The 2006-2007 is stronger than the L61 (2.2l) having some forged internals.


My ECM is not from a company. It was in the car with my motor. With HPTuners the E67 that is original to my motor can be tuned to do what I want. HPTuners can adjust just about anything with my ECM. I heard some ECMs purchased from companies requiring proprietary software could be difficulty to use and tune. The biggest hurdle is to get a base tune. There are some guys working this week on the same setup I have (except for a land vehicle with wheels) and tuning to SD like I need. I'll know in a week or so if they can help me out. If not, I think I have created a base tune that might get me started. It is truly amazing what you can do with HPTuners. Almost too much, that's what scares me since I'm not a tuner.


I haven't heard much heat problems from the guys I've talked to that have these ecotecs. I have heard heat soak after shutdown can cause some decreased in performance. I have already been considering ideas for cold air intake. I'm building my own doghouse so only limited by time and imagination. I built my heat exchanger for 300hp and can easily add more for very little cost. I may add a circulation pump with a timer, like a turbo timer, if I need to to continue cold water circulation after shutdown if I really need to. I'll definitely do a hard, long run to see how temps hold before I take it out to a remote location.


I don't plan on reducing boost. If anything I would go with a smaller pulley. The street guys are going down to 2.7" without difficulty and spin theirs to 7,000rpm. This would help with boost at lower RPMs and this motor has been proven to handle it.  I'm sure fuel economy won't be better than an NA engine but I doubt it will be as bad as my 2stroke. I've always run premium (another setting that can be modified while tuning) and now I won't have the added expense of $20-30 in oil per trip.


Noise? Yep, I'm sure. I wore earmuffs with my 2-stroke. Again, I have ideas on how to mitigate this as well. If I find something that works I'll post what I learn.


Manifold- It appears to be very well made. Nice powder coating though I would have been fine with bare aluminum. I'll let you know how it goes after I get to finally get out on the water. I haven't heard anything bad about them. It was from a sponsor on this forum, Jet Boat Base. Just send them a message. They will send you a price list. It helps that the US $ is much stronger than NZ right now. Shipping is a killer though.


Hopefully that answered all your questions.


2 last thoughts:

Yes, I love to trouble shoot and try something new. It's how I learn best. Sometimes costly, mostly costing time. Something I was troubleshooting/improving today will be in the attached pics. I didn't like the belt-pulley setup on the LSJ supercharger conversion. I tried gutting the A/C because you need that pulley for proper belt routing. It would work great but I went with a pre-fab engine mount and it won't fit with this mount. I love the mount but when you see how they route their belt it just barely touches the alternator. So I came up with my own pulley mount. I think the engine mount should come configured this way already. Maybe Jet Boat Base reads this and makes some changes. Again, not a complaint about them. The engine mounts are great and the fit and finish is incredible.


If all else fails I still have all the NA parts and it wouldn't take much to use the stock tune and modify it for stand alone. If I blow up the motor there are 2 more in town with moderate miles on them for $800. A new motor goes for $3k. There is no way you can find marine motors for close to that. I just sold my 17 y/o outboard for $4,300. Once running parts are a dime a dozen. New impellers will be more than my engine.

[Matthewf/Norbert/TuiDog]

AKliving - not even finished your project and talking about a smaller S/C pulley -  that's what we like to hear!   

[AKLiving]

 Advice/opinions wanted.
Does anyone know the minimum draft for a Scott jet? I'm only drafting  just 4-6" (10-15cm) when loaded light. I can shift some weight to the back but not much. I'm gaining very little to no weight in my conversion.
I'm considering going with a tunnel design (about 2") similar to many production boats designed for super shallow river running. My fabricator has successfully built them for various combinations but much deeper drafting. Scott Jet gave me a canned response to the question without answering it.
I don't see anyone where you guys are using tunnel designs and still run super shallow rocky rivers. Though this isn't really a debate between best designs.

[Maxxi]

Good day sir:
It does sound like you are well aware of what you are getting into so thats the biggest thing.

Oh and FWIW  I admit entirely  Cris at CBM (custom built motors) was great to deal with.   Although plenty of the things he told me were Poo like they are making the harnesses and that they bench test them.     Told me on a Monday they had the harness but oddly it took nine days to ship?  just long enough to order one from the other guy  and again.  Useless harness as four wires were simply in the wrong pin location.   The wiring diagram HE PROMISED  would be with the harness was a few lines on a blank page.   I recall telling him  he promised a MAP of  the State and he sent directions to his house.   That is clearly an analogy.   I must have been on the phone with that guy 20 times over just the harness and computers.   Always polite and said he would   "..... ....  ...  "  and push come to pushharder  he just didnt. 

Thats my experience perhaps other people have other luck.


RE  min draft for your scott.... hmmm  can not answer in inches but like i said I have the 750 Scott in a boat about 1500lb 16 feet long 5 foot wide.   I will admit with only two people and 1/4 a tank of gas I have to walk to the back of the boat to prime the pump;

Once full of water it never looses it.

Full tank of gas  the same guy and fishing gear and its not an issue.
I will also state my boat is set up to run shallow thus flat and as such has almost looks nose low when light and sitting flat in the water.  Gas tank is in under wind screen.

About your tunnel.... perhaps you could just put UHMW on the bottom and that would give you 1/2 inch tunnel so to speak.    Maybe a center strip kit?

Not sure how much you have run a Scott but I swear to god you can cover 1/2 of the intake and still get on step with only a little cavitation.    I have put it on the trailer several times and was stunned to see so many rocks in the intake as I had not noticed any issue while driving.
I have hit several gravel bars and FILLED THE PUMP  with pea gravel to the point the nozzle out back is 1/3-1/2  full of rocks... like it was pumping them....  push and pull and shuv until it was a float again and jump up and down on it to pump the rocks out of the pump with water and off you go again.   
No stomp grate.....  although I paid for one and the boat came with one it is one more thing JBM could not do right.   The pump cavitated like hell with it in.  After talking with Conrad Scott about it  I just took it out.  Never looked back.   I think the key is you will never put so many rocks into the intake you loose the ability to steer and so long as you can do that stick it on a bar and take the rocks out of the grate with a flat screw driver from underneath.   Just pry  left and right once between each bar and the rocks fall out.   I say again....  I have never had to do this on the river.  Just did not need to.

OMG the sun just came out   

[AKLiving]

Thanks Maxxi. Real world experience appreciated. I've heard from many that have similar experiences with running fine having the grate full of rocks. I am very fortunate to have come across this pump. I paid for a used Ford Pinto and received a brand new Rolls-Royce.

[AKLiving]

Getting much closer to realization.
It goes to the hospital in less than 2 weeks for the surgeon to perform the transplant. As many hours as I have spent getting it to this point so far I am sure glad (and my wife too) to take it to a shop to do the aluminum work.


Here is the progress so far. My pipe soldering skills need honing but the heat exchanger works great. I wasn't even flowing as much water as the jet pump would and the copper pip at the outflow was only warm to touch.


The engine needs to be tuned still so hopefully that will get done before it's taken to the shop. It sure is easy to work on while out of the boat.
https://drive.google.com/open?id=0B-htR6Muu1BZTkhQRTZlSjZPSDg

I can't believe I found parts for $89 shipped to my door. They appear to be genuine spicer parts. Even if they were junk at that price I could have a spare on hand.
https://drive.google.com/open?id=0B-htR6Muu1BZOTRNTGdnaUVENTA
https://drive.google.com/open?id=0B-htR6Muu1BZaE16NHBndlZoZ2c
https://drive.google.com/open?id=0B-htR6Muu1BZVktfdE85Wk5zWTA
https://youtu.be/e16GM-ZOQXE

[AKLiving]

I can't seem to upload jpg images no matter how small I make them. I get error file size >250kb even if they are less than 100kb so hopefully the google drive links work.

[JohnR]

Turn water on after you start engine. And turn it off before you shut engine off. Probaly wont matter with the high riser setup you have but it pays to be safe

[Paul]

I can't seem to upload jpg images no matter how small I make them. I get error file size >250kb even if they are less than 100kb so hopefully the google drive links work.

That the total file size across all the attachments in the post.

[AKLiving]

I will try to post more of my build when I can. I seem to struggle with trying to make my photos fit the file size limit and I don't have a server I put them on.
First outing with the family after the conversion. We went to Harding Lake, Alaska. A Beautiful day!!!
[/size]

Supercharged a 2007 2.4l LE5 GM engine from salvage yard. Converted my SeaArk 2272 MV from outboard to inboard. Scott 752 with 19/19 impellers, 111 trim nozzle. (love that trim for leveling out and getting rid of porpoising)Made 39.5mph (reproducible on GPS) at 4,700 rpm. Not bad for a tune that isn't finished yet and a rough guestimate on pump setup. I did a load test the other day when I was still only pushing it to 3,200rpm. I was going about 24mph at that speed. Then put 1,800lbs of water barrels onboard and got on plane like it was nothing toping out at 22mph. My draft was still only 10" with that load and I wasn't evenly distributed (could have used more towards the bow).


Man that supercharger whines when going over 3,500rpm.


https://youtu.be/yLcozQbBV5o[/color]

[AKLiving]

There's still a little work left to do on the boat, engine tuning and pump tuning.
Moose hunting is in a few weeks and I'm running well enough with way more capability than last year so I'm happy.


Maybe this winter I'll have some time to finish posting the build but for now I'm done.


Thank you all for not only the forum help but providing a wealth of information to be freely shared. There is no way I possibly could have completed this project without help from people like you.


Here is my final trials for the year. Sorry for the poor quality.


https://youtu.be/_Xd0bQ84MaY

[Scott Waterjet]

Great to see you have your new combo in action. Well done. Enjoy the pump!!

[AKLiving]

This turned out to perform better than expected. I still have tuning issues but the engine and pump combo didn't break a sweat. Trying to stay in the channel down river that had a huge log in the middle making each side barely over the width of my boat I finally got majorly stuck. The great part is that I went about 50+ yards in 2" or less of water. This was with about 2,500 lbs of moose, men and gear onboard. I doubt I would have had any problems if I were running with usual weight.
When we got home I found out we collected almost 1/2 the grate worth of debris and didn't notice a change in performance!
God blessed is with a beautiful moose providing over 600lbs boned out meat, duck, goose, and a white wolf.
Next summer I'll finish painting, sealing, and tuning. I'm done for the season since I don't have a garage and freezing temps have already come.

[AKLiving]

Running shallow fully loaded before the sand just wasn't wet enough. 
And why I want to reach areas others can't.
All I can say is that Scott pump is simply awesome!