Swap engines from OMC to Mercruiser

O

Oatsmandave

Seaman Apprentice
Joined
Mar 29, 2006
Messages
31
Hello fellow boaters!I have a chance to buy a 1991 Maxum 2100 with a blown 3.0 mercruiser engine for dirt cheap.I also have a 1988 Bayliner Capri with a 3.0 OMC.I am wondering how much of a problem it would be or if it is possible to swap the OMC to Mercruiser.The Bayliner interior is pretty shot and the Maxum is immaculate!! I am assuming that i will have to swap the motor mounts and the coupler.or not? This Maxum is to good of a deal to pass up($400) and don't want it to slip though my fingers if the swap is possible
 
Bondo

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,095
Re: Swap engines from OMC to Mercruiser

Ayuh,...

Do you understand the Difference between a Long Block motor,...
And a Complete engine,..??

Only the Long Blocks are the Same,... Everything Else is Different.....
 
H

HT32BSX115

Supreme Mariner
Joined
Dec 8, 2005
Messages
10,083
Re: Swap engines from OMC to Mercruiser

Oatsmandave said:
Hello fellow boaters!I have a chance to buy a 1991 Maxum 2100 with a blown 3.0 mercruiser engine for dirt cheap.I also have a 1988 Bayliner Capri with a 3.0 OMC.I am wondering how much of a problem it would be or if it is possible to swap the OMC to Mercruiser.The Bayliner interior is pretty shot and the Maxum is immaculate!! I am assuming that i will have to swap the motor mounts and the coupler.or not? This Maxum is to good of a deal to pass up($400) and don't want it to slip though my fingers if the swap is possible
Click to expand...

I did a similar thing replacing my (87) OMC 460 King Cobra with a (97) 454 Bravo III out of a wind damaged 98 Bayliner. I even used the complete wiring harness from the bayliner too (I kept my gages though)...
and bought a new Teleflex CH1700 throttle/shift quadrant and cables....

You should not have any problem doing the swap.

You'll (of course) need to pull everything out of both boats.

Take ALL the OMC specific stuff off the OMC engine and replace it all with the brackets, flywheel, coupler, flywheel housing etc from the blown Merc engine.

You'll also need to use the manifold/riser-elbow , dist/carb, harness alt etc (if it's any good) from the Mercruiser engine too.

The Alpha transom will bolt right in where the Kobra came out.

Use the Mercruiser engine mounts too if they're different but you might need to relocate the holes for the front mount.....(they're probably the same)



Get the correct service and installation manual from above and/or Boatfix.


Cheers,


Rick



EDIT. Ok I read your thread a LITTLE closer!!!

You want to put the OMC engine in the boat with the Mercruiser already installed.......(I must be reading impaired!!!:rolleyes:)


Same thing though....just a little easier..(you don't have to swap transom and drive) Take both engines down to the "long block" and put ALL the Mercruiser stuff on the OMC "long block" (which is what Bondo was saying in so many words!!!) and then bolt the "new" engine back in.

Buy the Maxum
 
chiefalen

chiefalen

Captain
Joined
May 18, 2008
Messages
3,598
Re: Swap engines from OMC to Mercruiser

I just did what you want to do just the opposite. You will need to remove the drive on the merc and the omc to remove the motors.

You will have to pull the motors out and put them side by side on a pallet and move all the externals EXCEPT THE DIZZY, or you can use the dizzy off one and put it on the other. The starter can stay. Save the starter on the other if it's still good and the timing cover.

You will need to move the coupler over. And you will need to use the manifold and riser.

The bell housing will have to be moved over.

Do yourself a favor when you have it out look at the oil pan real real close. And clean it good and paint it 3-4 times. Same for the timing cover, i painted everything when i had it out.

Good luck it will take a day to do it.
 
derekpfeiffer

derekpfeiffer

Petty Officer 1st Class
Joined
Apr 3, 2008
Messages
214
Re: Swap engines from OMC to Mercruiser

sounds like a fun project...wouldn't the 3.0 be a little under powered for a 21' boat??? just curious if you're going through all this work I'd hate to see you disappointed in the end results...unless you don't do many water sports and mostly just cruise.

Good luck,
 
chiefalen

chiefalen

Captain
Joined
May 18, 2008
Messages
3,598
Re: Swap engines from OMC to Mercruiser

3.0 is the easiest way to get back on the water no fuss no muss. No gear changes, cheapest, way to go.

Want more power buy the boat with the package in it, ain't so easy going higher in hp, glass work stringer work Y pipe and such forgetaboutit.
 
O

Oatsmandave

Seaman Apprentice
Joined
Mar 29, 2006
Messages
31
Re: Swap engines from OMC to Mercruiser

I haven't gone to see this boat yet but since it is a 125 hp engine,so I am assuming it is a 3.0 liter.I kind of thought it odd for a 3.0 to be in this big of a boat also.And yes,I think it will be a fun project to toy with for a weekend of beer drinking(as long as it isn't to many!) Thank you all for your input and figured I would have to go all the way down to the block and refit everything off the Merc. You guys are always a big help and will let ya know how it went when finished.
 
chiefalen

chiefalen

Captain
Joined
May 18, 2008
Messages
3,598
Re: Swap engines from OMC to Mercruiser

Now your posting something a little different then the op. The 2.5, 3.0 is a chevy block. The 2.5 is 120 hp, the 3.0 could be 130-140 hp.

The 2.3 is a ford. Make sure what your getting. You don't want the 2.3 understand. And i think the 2.3 is 125 hp. Stay away.
 
O

Oatsmandave

Seaman Apprentice
Joined
Mar 29, 2006
Messages
31
Re: Swap engines from OMC to Mercruiser

chiefalen said:
Now your posting something a little different then the op. The 2.5, 3.0 is a chevy block. The 2.5 is 120 hp, the 3.0 could be 130-140 hp.

The 2.3 is a ford. Make sure what your getting. You don't want the 2.3 understand. And i think the 2.3 is 125 hp. Stay away.
Click to expand...

Yeppers,I do understand about the 2.3s ,JUNK JUNK JUNK!! But you did help me out on knowing what is what.I didn't even know that Maxum even put Ford engines in their boats.I just hope this isn't a 6 popper also as I just want to swap the 3.0 block from the Bayliner to save a little dough and plus my engine has less than 80 hours on it. Thanks,Cap
 
F

fyrfightr

Petty Officer 3rd Class
Joined
Aug 13, 2007
Messages
93
Re: Swap engines from OMC to Mercruiser

Are you sure this is a 3.0? A 125 hp could be an L-drive. Which is a 4 cylinder 2 stroke outboard powerhead the US Marine tried using. If it is, the transom is totally differant from an I/O. If it is walk away as quick as you can...;)
 
O

Oatsmandave

Seaman Apprentice
Joined
Mar 29, 2006
Messages
31
Re: Swap engines from OMC to Mercruiser

Okay,I KNOW ,for SURE it isn't a outboard engine from the pictures I have seen.HOPEFULLY my dumb@$$ can figure out how to post the pics of the aft end of the boat.( i am BAD with comps.lol!) Did Maxum actually use Ford engines?And if they did,why would they use such a small engine for a 21 foot boat?Doesn't make any sense to me?My Bayliner Capri (with a cuddy)is 19'.5'' and has a 3.0 (which pushed it at 40 M.P.H. WOT)so that is why I was assuming the Maxum was a 3.0 liter engine for such small H.P.(125)Here is what I got in an e-mail about the boat.

(((((Here is the stats on the Maxum...It is a 1991 Maxum 2100 LDC / LDR / SC /SR 125 HORSE POWER... 20 foot 7" in length and 84 width...
I found the paperwork from the marina on what was wrong after I "won" it in the divorce... A piston went thru the side of the block on the upper portion of the L Drive.... also sd part of the lower portion has a bent piece of aluminum...(Oatsmandave is assuming the skeg?))))) I will post the pics of the aft end of the boat as soon as I figure out how to, Thanks,Dave
 
O

Oatsmandave

Seaman Apprentice
Joined
Mar 29, 2006
Messages
31
Re: Swap engines from OMC to Mercruiser

I know the "ex Hubby" in this ordeal tried to fry the motor cuz he knew the "ex wife" was getting the boat in "The Divorce".He made it a point to blow the motor and did a good job by pushing a rod through the side of the engine!!! He MIGHT have tried to to more to the outdrive also as I can see from pics of the prop(1 blade being broke off) and also her mentioning the "bent piece of aluminum on the bottom"(Skeg?)But she just wants $400 for the whole shebang!!Might be worth putting a couple grand into her to get her going and sell it NEXT year for a bigger boat!!The trailer is at LEAST worth the $400!!!(plus the boring trip to Iowa from Minneapolis)
 
chiefalen

chiefalen

Captain
Joined
May 18, 2008
Messages
3,598
Re: Swap engines from OMC to Mercruiser

Might this, might that, post when you really want some help. About buying the boat and fixing it thats for another forum.
 
Bondo

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,095
Re: Swap engines from OMC to Mercruiser

A piston went thru the side of the block on the upper portion of the L Drive....
Click to expand...

Ayuh,... You Don't want that boat,... No How, No Way.....
 
F

fyrfightr

Petty Officer 3rd Class
Joined
Aug 13, 2007
Messages
93
Re: Swap engines from OMC to Mercruiser

Like I thought. This is an L-DRIVE.

Follow Bond-o's advice..... RUN RUN RUN

The only engine that's going to fit in this boat is the powerhead off a Force 125hp outboard.


I have read of people that converted these boats to outboards by building a jack plate to put a new outboard on.
 
O

Oatsmandave

Seaman Apprentice
Joined
Mar 29, 2006
Messages
31
Re: Swap engines from OMC to Mercruiser

I am telling you that this is an I/O already!!! If I could figure out how to post a pic I would.It has a Alpha 1 outdrive.I
 
a70eliminator

a70eliminator

Captain
Joined
Sep 9, 2007
Messages
3,762
Re: Swap engines from OMC to Mercruiser

A 21' 91 Maxim in immaculate condition including trailer for 400.00 would already be sitting in my barn, that is if I was looking for a fixer upper which I'm not, already been there, even if it does need re-powered completely.
 
J

jakebrake

Petty Officer 1st Class
Joined
Sep 22, 2008
Messages
286
Re: Swap engines from OMC to Mercruiser

I believe they are trying to say "The motor is carap. no use other than as an anchor. only mounting an outboard to this vessel will make it worth the rubber in the tires the trailer sits on. run, run fast, run screaming naked through the woods if you must, but run from this turd....

or something to that effect
 
You must log in or register to reply here.
Top