1988 3.0 Mercruiser 140 hp questions
 

I am trying to figure out if a 1988 3.0 Mercruiser 140 hp motor will mate with a mercruiser pre alpha series outdrive. I have an opportunity to purchase the motor and want to make sure it will in fact mate up with the pre alpha. The person I am purchasing the motor from says of course..but looking for more opinions. It will be going into a boat that currently has an older 3.0 in it already.
Any help appreciated....Tim???...anyone

Re: 1988 3.0 Mercruiser 140 hp questions
 

Fred, while you're at it, why not also ask if any of the later model V-6 engines will work with that outdrive? I believe Nothinfancy is going to marine mechanic school, so he might know or be able to find out for you. Denny

Re: 1988 3.0 Mercruiser 140 hp questions
 

go over to boatered forums-you'll get your answer in a jiffy

Re: 1988 3.0 Mercruiser 140 hp questions
 

Denny....so you think something like a 4.3 would be better..I am on a budget as usual!!! I do not want to have to change out my outdrive or mess with motor mounts etc!!!!
Oldfielder...I will post question on other site (great info over there) I did not know it even existed

Re: 1988 3.0 Mercruiser 140 hp questions
 

I've gotten a lot of advice there-there are some serious experts on that forum

Re: 1988 3.0 Mercruiser 140 hp questions
 

just grab an old scarab or chapparall, four wins,etc beat up a little you can always find used up hulls from the gas happy "boat drivers"... or pick up the quintesential Bayliner prolly cheapest in the "edition" that looks like a floating pop up camper with a point that has cockpit railing like a "holiday in express" in balcony...depending on how much your willing to spend you could end up with newer technology at a huge discount. you can steal a lot of good parts off it to to resell then giddyup to the dump with the hull or make a planter out of it if your really feeling frisky....lol

Re: 1988 3.0 Mercruiser 140 hp questions
 

BruceB..good idea on donor boat...never thought to go that route...guess i will used jaxed and look for bayliner etc.
Still waiting on email to get access to boatered...wanted to keep the boat as close to original setup as possible though.

Re: 1988 3.0 Mercruiser 140 hp questions
 

350 mpi.......in some of those turds

Re: 1988 3.0 Mercruiser 140 hp questions
 

Fred, I recognize that a near-stock original setup is probably the cheapest, but as a mechanical engineer I'm just partial to smooth running machinery! A large displacement I-4 w/o balance shafts will buzz quite a bit but you might not care about that, provided it's reliable. Just thought that while you're looking around, it might pay to think out of the box in case you find a deal on a more modern set-up. It's probably not that hard to find a bayliner full of rotted plywood with a fairly low time engine/outdrive, so finding a donor boat could be a viable option if you have the time and like turning wrenches! I think Skip has found that replacement parts for some of the really old outdrives can be pretty expensive. A V-8 would be way too much weight unless you wanted to spend a lot of $ for aluminum heads and fresh water cooling! The 4.3L V-6 isn't naturally balanced either, but it's a little smoother than the big I-4, similar weight and more power. There was a Seafari on here some time ago with that setup and it looked like a neat installation.

There's a reason they did 3 valve jobs on that old engine as described in that original ad you sent me: it was underpowered with that 120 hp engine! Sounded like they did a lot of diving, and if they loaded that boat up with 4 divers, tanks and gear, and ran it w/o a vacuum gage, they probably ran it well under 5" vacuum, which will burn valves pretty quick. That boat is not underpowered with a 140 if you don't overload it . . . 2 different 140 I/O Seafari's have made the 170 mile trip to Green Turtle in the Abaco's with me, and they would run about 23-25 mph at 7" vacuum. They weren't heavily loaded however, and because they're 5 mpg rigs, they didn't have to carry nearly as much gas as I did with my old 115 V-4. They burned about 45 gallons to my 65 gallons! :eek:
Denny

Re: 1988 3.0 Mercruiser 140 hp questions
 

im not an I/O guy, but i will tell you that a 4.3L chevy motor is pretty durable. i had one in my s-10 and sprayed nitrous thru it. at least 6 10 pound bottle probably more and one time it hit the speed limiter of 98 mph and the pcm shuts off the fuel but it kepy spraying. didnt die after that. no problems with that motor.

Re: 1988 3.0 Mercruiser 140 hp questions
 

Once you jump to a 4.3 you might as well do the small block if it fits nicely.... It will be a little more weight but also a little more forward

Re: 1988 3.0 Mercruiser 140 hp questions
 

I like BruceB's idea about stripping the Bayliner for the powertrain. If I had thought of that before I repowered 2 years ago, I probably would have gone that route. I put the inline 4 (2007 TKO mercruiser) in my 76 seafari. Before I did that I looked real hard at the 4.3 (you could get this with fuel injection, and mine is carburated). I looked at the seafari bushwacker was talking about when it was both in the water and on the trailer. If you could somehow put a drive shaft between the motor and the outdrive and move the block all the way to the forward most position of the engine compartment, you would be all set. As it was, the stern sat a little too low for my comfort level, the thru deck drains were almost awash with the boat sitting at the dock, and I believe the owner had heavy chain in the forward hatch in the cabin to help level the boat. I would add that the installation was very clean, and professionally accomplished. Mine runs plenty, especially for where I use it with the 140 in it, and I still can't get over the fuel consumption, which at 3600 cruise, ~20kts light load is in that neighborhood of 5mpg, but I would have loved to have 220 back there for when it was time to go. Just didn't think that the stability vs power were worth the trade off in the environment I am currently in set up to use the boat in (I spend most of my time fishing in 2-4' rips in long island sound, and that body of water is such a washing machine, there are hardly ever conditions where running over 20kts is comfortable to any seated rider, kids)

Re: 1988 3.0 Mercruiser 140 hp questions
 

How much are you paying for the 3.0 Merc I/O? I think I know where there is one, maybe save you some $$$

Re: 1988 3.0 Mercruiser 140 hp questions
 

Thanks all for the great advise etc..more things to ponder..
Denny I will drop you another email
77SceptreOB...I have a chance to pick it up for $450.00
Let me know what you found...email me at fdheld@bellsouth.net
Thanks again all!!!
Bayliner idea looking more interesting
-FRED