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It is possible to swap a 3.0L omc engine(omc stern drive) with a V8?

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cjensen_68

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I am looking at getting a boat but am not too sure about the motor. Its an 80s sunray but I want to know if that motor goes out what does it take to put in a V8 like a 305 or 289? Will it hook to the OMC stern drive that is already there? I'm new to this and would like to know my options before I get this and find out I should have waiting to get another boat. How cheap is it to rebuild the 3.0L engine also?
 
haha- chief summed it up - you have but one chance to save yourself from OMC headaches...
all boats give you headaches, but Mercruiser migraines throb less

3.0's are expensive to rebuild because there is few automotive equivalent parts. Boat engines rarely need rebuilding though.

If you want a V8 - buy a V8
go buy a Mercruiser Alpha One 260HP Chevrolet 5.7L V8 powered boat. It is one of the most common and plentiful drive trains in the marine market and parts are common and more affordable than OMC parts.
 
Thank you for your guys imput. I was thinking the same thing with getting the V8. My is wife sitting here is telling me to wait and find one with eveything I want in it....basically a v8 and seats more than 4
 
I already have an 86 beretta with the Merc 170 that I bought..It has a 4.3 L alpha one stern drive..Will that stern also hook upto a v-8...Does anyone know?The motor doesnt turn over so I dont know how bad it is on the inside right now,,So i would rather just swap the engine if possible..
 
chiefalen said:
If it says omc stay away
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Unfortunately, or perhaps "fortunately", this is very good advice. :)

hystat said:
haha- chief summed it up - you have but one chance to save yourself from OMC headaches...
all boats give you headaches, but Mercruiser migraines throb less

3.0's are expensive to rebuild because there is few automotive equivalent parts. Boat engines rarely need rebuilding though.

If you want a V8 - buy a V8
go buy a Mercruiser Alpha One 260HP Chevrolet 5.7L V8 powered boat. It is one of the most common and plentiful drive trains in the marine market and parts are common and more affordable than OMC parts.
Click to expand...
Not too popular a comment amoung the Merc guys, but the Volvo Penta will cause you even less Migrains! :cool:

Benjamin A. Hill said:
I already have an 86 beretta with the Merc 170 that I bought.. It has a 4.3 L alpha one stern drive.. Will that stern also hook upto a v-8...Does anyone know? The motor doesnt turn over so I dont know how bad it is on the inside right now,, So i would rather just swap the engine if possible..
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Best if you were to post your questions in the Mercruiser forum, where you'll receive many more comments regarding this.

Long and short of it:
The 170 was short lived, and may not be a good choice to go back with.
It was Merc's version of their own aluminum block large bore 4 cylinder, and used the Ford 460 cylinder head.
Very powerful engines, but do offer some issues that most don't wish to deal with these days.

The over-all drive ratio was unique to the 170, so a change here would be necessary if a V-8 was to be considered.
Do your homework first!
 
Ask your very smart wife if it'a ok to spend a tad more and get a modern motor and drive after 91' then you will be getting a merc say with a gen 2 drive.

If you look on ebay you will see them with a trailer galore.

And before you buy ANYTHING ask here again.
 
So what would be some things to look for when purchasing a boat? There is a 95 bayliner 2050 with a mercruiser 5.0L and alpha 1. Just had 100 hr service and has receipts for it. He's asking $6k. Is that high? says everything is working just minor cracks in a couple seats from weather. I do like the sound of getting a boat that doesn't need anything done to it.
 
IMO, the Volvo Penta "cone clutch" drive will be superior to the Merc "Dog Clutch" engagement "A" drive.
The A drive requires the SI (shift interrupt system).
Search the forums on issues with Dog Clutch gear engagment and the SI......, and I won't have make negative comments about Dog Clutch gear engagement.

An "A" drive will always offer some degree of shifting issues.... and will always be a single prop drive.
Conversely, the V/P drive is cone clutch.... and generally will not offer any shift issues..... and any can be converted to the Duo Prop.

The Volvo Penta boats will generally bring a bit more in price... both during YOUR purchase, and when YOU sell.
So this can be a good thing!
However, if Volvo Penta is to be considered, Bayliner did NOT use Volvo Penta after approximately 1986 or so.
(Brunswick Family Boat Company owns Mercury Marine... so all gasoline B/L's today are now Merc)
So you'd be looking at boats other than Bayliner if Volvo Penta were to become important to you.

So I'm going to suggest that you:

1..... look for a V/P powered boat..... preferably prior to the SX or DP-S style drive models (the AQ series.... the good stuff).

2..... have a survey performed (structural and mechanical).... this will be money well worth spending that could easily save you an unwanted expense later on.

3.... do a Sea Trial...... and see if the boat performs as you would expect it to. Be sure to load the boat as YOU normally would as though you owned it.
(the ole trick is to Un-Load a boat that is being sold.... making the sea trial more impressive!)


FYI: the AQ series drives ran along side the SX and DP-S drives up through approx 1995-1996 or so.
These would be the Non-Gimbal suspension type drives.
IMO, these drives offer much better geometry, easier service, and much easier DIY service.

Like said.... this is the Good Stuff! :D

.
 
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cjensen_68 said:
So what would be some things to look for when purchasing a boat? There is a 95 bayliner 2050 with a mercruiser 5.0L and alpha 1. Just had 100 hr service and has receipts for it. He's asking $6k. Is that high? says everything is working just minor cracks in a couple seats from weather. I do like the sound of getting a boat that doesn't need anything done to it.
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sounds like a good boat, but a survey or at least a once over by a knowledgeable tech is in order.

Rick loves his VP's, and so do I, but to buy a remanufactured AQ series drive, you'll spend what you can probably get that whole Bayliner for..
and if you ever need an outdrive for that Bayliner 2050... $1350 gets you a brand new one with no core charge and a 3 year no-fault warranty

That Bayliner will also have power trim, a rare option on AQ series drives. I couldn't stand a small i/o runabout with no power trim.

I love Bayliner Capris, but then I am biased.

I also predict SEI will make a duoprop Alpha lower some day.. heehee...
 
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Friend has the 19' classic. 3.0 runs like a raped ape. Great on gas also.

I too think it would be good to buy have someone who knows boats look at it first and test drive it on the water.
 
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