I Need 4.3/5.0 Swap Tips

My 502 EFI plugged into the wiring harness on my '83 and everything worked. I would look for a 350 EFI, but if not a 5.0 EFI with accessories for 2500 is a good deal.
 
Well I certainly agree that the 350 and 305 are size identically the same and 300 horses always beats 260 horses. :thumbsup: Are there the dollars in the budget to make that happen? :smt017
 
Well, I didn't do anything. After heading down to look at the 5.0, I started thinking "hey if it's fuel injected there's got to be an ECM module to think about, etc - maybe it is not an easy swap". So while I'm driving down to Georgia to get that engine I call Hall Marine and the service mgr did say that it would still be an easy swap, but they don't mess with old swaps and he referred me to some guy he knows that Hall sends that type of work to (I suppose Hall would work on my Sea Ray if it was new, but old stuff is too much hassle for them). :huh:

So I call the guy that Hall Marine suggested and he says well maybe it might be easy but probably not; it's not a simple drop and swap at all. There's several different complications that could arise (not only from the carb/ECM fuel injection swap issue but also the year mfg difference visavis coupler mounting and other stuff) :smt017

Now I'm getting worried as I continue my drive to Georgia. By this time I had talked to eight different "experts" - five of whom are certified Mercruiser techs - at six different marine shops/suppliers and no one agrees with anyone else about anything. I'm not going to write a novel for this post but I haven't even touched the surface of several other areas of inconsistent advice concerning items such as using my original Alpha and whether it would need to be regeared to handle the larger engine or not and a ton of other crap I have mercifully chosen to forget. It was crazy - it felt like I got nine different opinions from eight different experts. I may be a little slow to grasp things, but that right there is starting to tell me that this is not a job a newbie like myself should try to tackle DIY.

I'm going to find someone to do the work with the intention of either doing a complete rebuild of my original engine or purchasing a longblock. So I'll end up with my same engine power but at least it will be warrantied and I'll KNOW about what it will cost since there won't be any "surprizes" doubling the original estimated hours it would take to do a swap.

On first glance all of this doesn't give much info on actually completing a real swap, but at least if someone finds this thread in the future it will let them know how complicated it might be... and to tread lightly with an open mind when they get advice about getting it done. I was rather surprized to talk to so many "experts" - all of whom told me they had umpteen years experience and maintained their yearly Mercruiser training and etc - and yet they could not give me consistent advice on the feasibility of this project. Maybe it would have been easy but then again maybe not. Sorry guys but I cannot afford the dollars it may take to be the guinea pig that finds out. See ya back again soon on the water with another little engine in our little Sundancer. :smt001
 
Gerald...........Unfortunately there probably just aren't that many marine mechanics that have made the engine swap you were thinking about. So while they have a lot of "general" knowledge they may be lacking the specifics of what else needs to be done on your particular model boat to ensure a good installation.

So in retrospect, I think you are making the right choice. A fresh rebuild or a new engine or shortblock should both yield a powerplant that's a bit more powerfull than your current tired engine. So maybe it's not that bad of a choice overall. While they are doing all this work you may also want to consider the possibility of replacing certain components of your exhaust system depending on their condition since it will be less expensive to do this now rather than later. The same thing goes for all the hoses, belts, etc. unless they have been replaced recently.

Keep us posted as work progresses. :thumbsup:
 
Gerald, Sound like you're making the right choice. Hope to see you back on the water soon :thumbsup:
 
Oh yeah.... I don't want to have to worry about this again for a very long time. Whether it's a rebuild or reinstall-on-longblock project, I will make sure that everything is replaced - all belts and hoses right down to new hose clamps, EVERYTHING. I'll basically have an entire new drivetrain since I blew the Alpha last year and totally rebuilt it. For all intents and purposes this should be a very reliable almost-new unit in a couple of weeks. I do want to look inside of the risers and stuff to make sure they are still in good shape; if they are not, they will get replaced with every thing else. I'm hoping for them to be in good condition since they spent 99% of their life in freshwater and not saltwater.

Stuck with the original power level and not a big v8, I won't be pulling any skiers or racing gofast boats, but with a new life on the drivetrain I WILL be ready for anything short of a rendevous to the Bahamas this summer :thumbsup:
 
Gerald, Just a thought, while the engine is out would be an excellent time to check all of the mounts to be sure they are not going to fail anytime in the near future. Possibly rotten wood in the front mount area.
 
Good point Nolan. I did note that one of the starboard engine mount bolts was tilted instead of pointing straight down so I may indeed need to address that issue also once the engine is out.
 
What you need to do is take Durrango to "Funnest Animals" show and win the 10k 1st prize. Then go for the 350Mag B3 combo.! :thumbsup:
 
STIHLBOLTS said:
What you need to do is take Durrango to "Funnest Animals" show and win the 10k 1st prize. Then go for the 350Mag B3 combo.! :thumbsup:
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:lol: :smt043 :lol: :smt043 :lol:

Does it come with a hemi :grin:
 
Just another temptation I'll have to resist :smt001 I'm committed now; they've already ordered the 4.3 longblock and I've paid a deposit on it.
 
Yep, technically it does but oh well, the wallet wins.

And in any event, I'm not too sure the difference would have been that much unless I went up to a 5.7. The standard 2 bbl 5.0 puts out only 15 more hp than my 4bbl V6 but weighs a hundred pounds more; sounds like pretty much a wash to me (although I do assume the 5.0 would have more low end torque). The other fuel injected 5.0s have enough extra power to be worth it but would put me in experimental swap territory which I'm sure could be done but I'm just not in the position with the time and money it might have taken. I have no doubt that this would have been an easily doable swap - I've faced modifications a whole lot more extreme than this in the 4x4 world - but I just couldn't find anyone around here who could give me any confidence at all that they were capable of taking on anything except regular tech maintenance work.

Plus the more I thought about it the more I liked the idea of having a new warrantied engine :smt001

That V8 will be in my next (bigger) Sundancer once my more-footitis becomes contagious and the Admiral catches it from me :grin:
 
GJarrett said:
Yep, technically it does but oh well, the wallet wins.
......

That V8 will be in my next (bigger) Sundancer once my more-footitis becomes contagious and the Admiral catches it from me :grin:
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You had better watch out talking like that Gerald. My wallet was really hurting when Judy keep saying how nice that 45' plus Sedan Bridge looked when we were in Charleston. She may catch that footitis worse than you. :lol: :smt100 :lol:
 
Good News Chuck. I just got back from Charleston tonight. There is a 44 Sundancer available now. It will save you big dollars over that Sedan Bridge. Jim will be glad to talk to you Monday morning.
 
Hey Paul thanks for the heads up, I'll make sure Judy does not see that message. I thought we were freinds. My wallet can not even begin to think about something like that, what with college, etc. But what is it they say, "You've gota have a Dream" :thumbsup: You'll have to start a new topic about the HH trip :thumbsup:
 
I decided what the heck; I'm gonna go diesel. And if I'm gonna do that, I'll just go all the way and get the most torque and horsepower available. Here's photos of the crankshaft and cylinder bank they're building for me.
rta96c_crank.jpg


rta96c_cyldeck.jpg



I'll probably have to find a bigger boat to fit it into though :grin:
 
GJarrett said:
Right now my biggest concern is where to find a motor hoist that is high enough to clear the boat and trailer since a standard auto engine hoist is about 6 ft too short
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If you were tackling this yourself, you could hire a tow truck with a hydraulic boom to remove the engine in your driveway. A friend of mine has helped me several times. I just prep-ed so he was in and out.
 
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