Looking at a motor - I need input

saltydogjeff

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I've come across a great price on a great vehicle which is a 5.2L 1999 Dodge Ram Van with the actual vehicle portion being rusted/retired/done. I have been running this through my head, about ready to whip out the cash, but I got to vent.

The engine runs in great condition, it sounds like a beast, multiport fuel injection, smooth enough to sleep, distributor, very little issues seen with the engine. Now, the issues are it is electronic fuel injected, has a computer, must be converted to marine use, and this is my first time.

A couple of questions are: (1) what do I do about the computer? Is it pretty close to the 1:1 swap over electrically? Can somebody load me a wiring diagram? How do I work with actually protecting the computer? Does it go in a box aft, do I load it under the dash and run wire forward and aft?

(2) Please check my parts list - exhaust manifolds (2), intake manifold, distributor, starter, alternator, brass plugs, new coolant pump impeller, and camshaft to fit application. What do I do about the fuel line?

(3) Wiring (again) - there is like a MAP sensor, vacuum on the valve covers and manifold, I don't know about the crank shaft sensors, coolant temperature sensors. Are there any sensors that are not required anymore and that requires reprogramming the computer? Like it was for automobile application, now it will not need to shift anymore - what goes on in the engine computer?

(4) Connecting to an outdrive: I understand Mercruiser Alpha Ones. What's the deal with getting the power out the back? I could look at a schematic and get a good idea. This is more of a "Hey - all 5.2L are still single speed - don't think about transmissions" type question, but I am still knowledgeably in the dust about getting power from the crank shaft to the drive/power (for any motor). This is me - "Power comes out the gimbal bearing - make the splines fit" - attitude.

(5) I am wondering what this can power. I only have 3.7L 22' experience. Looking for boats to fix and motors to put in em. Do I need to find a specific boat for adaptation?

-All inputs appreciated, request right forum as I only know the Mercruiser with 3.7L 470 named Bessi.
 

Bondo

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Ayuh,.... I think you'll find 0, that's Zero marine parts available for that motor,...

Chrysler has been outa the marine biz, since the very early '70s,.....

Chevys move boats today,....

Ford got outa the marine biz in the mid-'90s,....
 

HT32BSX115

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(5) I am wondering what this can power. ........................ Looking for boats to fix and motors to put in em. Do I need to find a specific boat for adaptation?
Howdy,

Assuming you can find jacketed manifolds, marine starter, alternator (mounting brackets) and dist, there might be a Velvet Drive that will bolt to that block and flywheel. so it could go in an inboard maybe......

Forget about connecting any stern drive to it. Although you could probably build one-off parts to do it if you had a full service machine shop at your disposal .......... it would not be worth it even if you could do all the work yourself.
 

Scott Danforth

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the 318 (5.2 liter) has been around since marine times. however it wont fit anything mercruiser. and you would need to strip it down to a short block and heads, keeping only the short block and heads and build it into a marine motor with the right parts.

you would be throwing away the entire computer, current intake manifold, distributor, etc. to buy correct marine components.

that endeaver alone could cost you up to $2k in parts alone.

leave the 1999 dodge 318 in a dodge vehicle. if you want to buy a marine motor, sto replace your 3.7, look for a complete bob-tail 4.3
 

thumpar

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Those run cats and o2 sensors. You won't find a solution for that.
 

saltydogjeff

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Got it.

Went to the local auto recycling place and dudes got a lot of blocks and some pretty sweet prices. 4.3L already stripped it for the parts he needs, which was the alternator, starter, and something else that I need to check tomorrow. He also said he would ask about any 5.7L around. :faint2:
 

HT32BSX115

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I only have 3.7L 22' experience. Looking for boats to fix and motors to put in em. Do I need to find a specific boat for adaptation?

Maybe I misunderstand what you're asking.....

Do you have a boat now that needs to have the engine replaced?
 

saltydogjeff

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I currently own 1 boat with 1 motor. I am in the middle of diagnosing motor 1. But, the boat is really coming together, so I am looking at another motor, possibly for this one if it is a cracked block, or as a second project while this 1 boat is out on the water.

I was introduced to the "free" section on craigslist which might not have been a good idea, because there are boats there. I have been a shade tree worker thus far.
 
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Bondo

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I was introduced to the "free" section on craigslist which might not have been a good idea, because there are boats there.

Uh-oh,......
 

saltydogjeff

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That is kind of what I am thinking... like I do not want a #$@@#$ quality product though...

There are gems all over the place and I am looking to gain experience.
 
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Scott Danforth

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Free boats are the most expensive boats in the world. I can't afford a free boat, my reasonably priced one is already expensive
 

HT32BSX115

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I currently own 1 boat with 1 motor. I am in the middle of diagnosing motor 1.
Ok,

I think I saw your other thread. You didn't reveal what engine and drive it is........

It would probably help if you were a little more specific instead of "I currently own 1 boat with 1 motor"...........
I only have 3.7L 22' experience
I guess that means you have the infamous 470 (or it's derivative)?


Yeah......"FREE" boats are usually NOT Free in the long run.....
 

Silvertip

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A boat and whatever it contains can be absolutely free. However having something free that cannot be used unless a considerable amount of time, money, frustration, and nagging from a domestic partner can result in the conclusion that one is "penny wise and pound foolish". Whatever engine you need/want/find should come from a truck, not a car. Truck camshafts are closer to marine spec than cars. GM engines are readily available for your boat (assuming that's what this boat contains) and even if you end up with a rebuildable engine, parts are readily available. Should you succeed in transplanting a Mopar engine in the current boat, you best be prepared to take it with you to the grave as nobody (except for someone really uninformed) would consider buying it.
 

HT32BSX115

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Should you succeed in transplanting a Mopar engine in the current boat, you best be prepared to take it with you to the grave as nobody (except for someone really uninformed) would consider buying it.
Yes.....and if someone did, shortly thereafter, they'll be right here asking where to find parts and how to fix it!:facepalm::facepalm:
 
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saltydogjeff

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I picked up a 4.8L V-8 Vortec, because the guy offered it for the same price as the 4.3L V-6 Vortec... I didn't take the time to research because he gave me the choice on the spot. I thought Chevy, thumbs up, but I don't see anything that resembles a 4.8L on mercruiserparts.com. A little help?

The farthest I got was that the 4.8L shares the same block as the 5.3L, but they use different heads (and all the good stuff that goes with it) to provide the extra volume. Still no luck searching for the 5.3L.
 

thumpar

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The 4.8l and 5.3l were never used by Mercruiser. You are not going to find the externals to make it work.
 

saltydogjeff

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I talked with the guy today. He says he can get me a 350 or a 4.3L.

I dunno. :fencing:Looking at parts.
 
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saltydogjeff

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I went and picked up the SB Chevy 350. It was out of a 97 Tahoe, casting number 10243880 with a large 880 stamped on the side. It has a roller lifters and I haven't gotten under to the mains yet. I am still in the planning phase looking for some recommendations of bang for the buck. I want a high torque, high power... I guess it is the money thing that has me worked. I have thought about turning it into a stroker. This route along with a new camshaft and increasing the rocker arm ratio are what I am thinking. This requires machine shop, basically all new internals for a stroker with crankshaft, rods, and pistons. What would you do in this situation?

​Outside of the ideological, what's the damage using the 5.7L ECM for a stroker, or any other modification like changing the camshaft? Does this require flashing with a new program curve? Is there any marine ECM options out there?

​As always - thanks for the input. Getting cold.
 

GA_Boater

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A truck ECM won't work well with a marine engine. No CATs, no road speed sensing, no tranny, no O2 sensors and no a lot of other stuff.
 
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