Offshoreonly.com - Is the mph correct for specs??

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Quote:

Originally Posted by Martin718 (Post 3740163)

Just to clarify it's a 3 blade prop and I called a prop shop he thinks we are close enough to where it needs to be not to mess with it. For what it's worth he said the tech props are good props.

It was multiple test runs in multiple conditions it runs 58 consistant and like you said I feel it's good actual data. I might be new to boat stuff but I build race cars from ground up.

As far as issues go it had a serious electrical issue when I got the boat, I have since replaced 4 batteries, distributor cap, rotor, coil, wires ect.

It had an issue that was causing the fuel pressure to drop and pump to cut out at 3,000 rpm so I listened to what a few on here believed it to be an put 8 new injectors in it, that didn't fix it so I put a complete new cool fuel system and regulator on it which also didn't fix it. Ended up being the coil or the coil ground.

I still feel like there is an electrical issue and I'm sure it's a ground, any time you hit a switch or operation the voltage gauge jumps or drops if holding an operation it'll drop 2bolts on the gauge which does that mean its dropping 2 volts in actuality? No but that's what it shows, in my opinion it shouldn't move a mm as I have 4 batteries wired in that are used when battery selector is on all.

Is there a possibility that the alt is bad? Yes
Battery bad even though all are brand new? Yes

The wiring seems to be a common problem in boats as most are fiberglass so grounding can be tough. I generally replace his old connections daily and will continue too. Any splice or wire connection he used was not a weather tight connection nor brass or copper so a lot of them are corroded and breaking. I'm replacing correctly as I find them but I've made two boat trips one after 10 hours of driving where I spent the ENTIRE weekend FIXING the boat not enjoying. This is what I'm trying to avoid

Baja attaches a crap load of grounds to the rear bellhousing bolts, they do not use a distribution block like most. I would clean those connections well. They also use two main ground cables, check both of them.

Sorry to hear of your issues. Have you checked the base and 3000 rpm timing? if you are turning a 20 oitch 3 blade you should be on the rev limiter. For the most part on a single of your size a 454 and 502 will run the same prob, not much diff in HP.

On a side note there is a 500EFI in the classifieds dressed and ready to go, with CMI headers for $10k. That engine will increase the value of your boat, get you the speed you want(should get 70 mph), run the drive you have, and you will have your old MPI to sell which will pull $5-6k in the spring :) If it was me......

http://www.offshoreonly.com/classifi...o46758-en.html

will drop right in complete like it has been there all along. Do nada value of your current set up, then change to 470hp :)

Boats with stock blue engines pull much more money in the used market than aftermarket mods, and are easier to sell!

I agree the timing was a concern but how do I check the timing because I was told you have I have a scan tool to override the conputer compensate

Quote:

Originally Posted by Martin718 (Post 3740216)

I agree the timing was a concern but how do I check the timing because I was told you have I have a scan tool to override the conputer compensate

Use a metal paper clip cut in half for a jumper to put it into service mode. I think it's A to B but not sure(written down at home) but you could do a search on here.

You don't need a scan tool to put it in to base timing mode, just a short piece of wire to short the 2 pins in the diagnostic port which is located by the ECU on the back port side (left) of the motor. I can't remember the 2 pins for sure, but think it is pin A & B. Someone know off the top of your head? Once in base timing mode, rev it to around 2000rpm and set your timing to what your manual says, some are different, but mine says 8deg. Last 454 I did I think was 6deg.
As far as your thoughts on electrical, you are not dropping 2 volts, but is at the dash gauge. Most boats do that and I agree that the electrical is marginal in most boats. If you check power with a digital meter at the motor, and alternator connections it is not dropping. Mine does the same thing and I hate it, but everything works fine. To fix it, I think the power leads to the dash should be 6ga to compensate for the drop in the line but most I have seen only are 10ga.
It sounds like you are getting everything you are going to get with the cuurent setup for speed and probably prop. It doesn't sound off to me, and I really like the 500efi, if it is an option because you can sell what you have, be turn key, increase resale value, and gain a lot.

Yep, just did a quick search and pin A & B it is.

Is that not a lot of hours on that 500efi? 400plus??

The top end was rebuilt at 300 hours and the top is where the problems are usually at with 500efi. The bottom end should last 800-1000 hours if there are no major problems on the top.

Maybe my 454 and some cash :)
I am in AL

Quote:

Originally Posted by Martin718 (Post 3740216)

I agree the timing was a concern but how do I check the timing because I was told you have I have a scan tool to override the conputer compensate

As others have said you don't need a scan tool but I would highly recommend getting one. They are about $400 from rinda and can save you a lot of time and money from just throwing parts at a problem. If you ever go to sell it you will have no problem getting $300 out of it used. Also, have you done a compression test?

Quote:

Originally Posted by Martin718 (Post 3740273)

Maybe my 454 and some cash :)
I am in AL

WOW, how lucky is that? Depending on where they are to you, you could just drive there, look at it and talk to them about details. You could swap that motor out in a weekend1

Yes I have done a compression test and all were in the 140-150 range with my old wore out gauge.

Also as far as throwing parts to it I took it to a marine dealer an had them scan it ect and it showed ZERO codes even while it was having the fuel issue ect. They are the ones said it needed the 800$ fuel pump and labor.

Quote:

Originally Posted by Martin718 (Post 3740292)

Glad to hear compression is good. The scan tool is still nice to have. Even though it did not have any codes in it it is nice to be able to hook it up while you are on the water and read real time data. I love mine and would not be without it.

Yea it wouldn't be a bad investment at all

Quote:

Originally Posted by Martin718 (Post 3740163)

...I have 4 batteries wired in that are used when battery selector is on all.

Is there a possibility that the alt is bad? Yes
Battery bad even though all are brand new? Yes

4 batteries? That IS another surprize. What type of batteries?
Four starting? Four dual purpose? Any deep cycle/trolling
motor batteries? If you are intent on keeping 4 batteries then
I suggest 1 starting and 3 deep cycle/trolling motor batteries.
However you should never use your battery selector switch
set to ALL. Your engine will NEVER be able to charge all those
batteries while running around the lake. Use your engine to
keep the starting battery fully charged ONLY. Use shore power
and/or a battery charger to charge up the stereo batteries. If
this boat was run for years the way you are doing it now, then
your alternator is probably worn out.

You are correct that a lot of people are not reading and
comprehending your thread. You are giving the pertinent
information, albeit in stages, and everyone should pay
attention so as to give you correct info. However you must
understand that each of these "surprizes" will rob a MPH or
two each. Next thing you know you are talking about real
speed losses. Which is where you are now.

Two batteries are in series to the starting On selector one two are in series on selector 2. When we sit I run the radio on 2 when I start it it's on 1 and when we are running down the river it's on ALL

All 4 are marine deep cycle batteries

Well the 200lbs of stereo and subs in the front and 2 extra batterys is about 350lbs extra, in the bow 200 lbs WILL absolutely kill your boat combined with a full tank of gas, 5 passengers and 2 extra batteries, WOW, 58 would actually be a realistic speed- But, you could only turn a 23 to 4200 and went almost 60 mph with a 20 pitch at a very low rpm, take your prop off, remove the six nuts clamping your bravo to the gimbal and wiggle it off, put it in gear, spin the input shaft until the output shaft goes exactly one turn-this will tell you the drive ratio , end the unknown question and make a decision of which way to go, Smitty

FYI, I have had my 3 kids teenagers in the cuddy a coupel of times and it kills my top end by about 5 mph, so the weight in the bow absolutely kills the top end. It fells like I am dragging a small anchor.

Quote:

Originally Posted by Martin718 (Post 3740459)

You will continue to have problems with the set-up above.

Quote:

Originally Posted by dbkski (Post 3740714)

You will continue to have problems with the set-up above.

I agree, hopefully he means parallel...24volts ain't good...

BAM Marine has a speed calculator on its web site. When you take the weight of your boat (4800), additional stereo and batteries (350), 3 passengers and a supermodel (700), and 40 gallons of fuel (250), 6100 pounds total and take your 385 HP of the 7.4 EFI and the constant for a straight v hull with a low drive height, you get a predicted speed of 58 MPH. You can go to this web site and determine how much HP it will take to push so much weight so fast. It will take either a lot more HP, less weight, a higher x dimension, or a combination of these to go faster in your Baja.