Merc 140 all seem to have issues WTF?

[joetheis]

I'm always looking for my next boat!
I have a 19' Grumman SF fishing boat with a 'Rude 70. Good boat, not the best for the St. Lawrence me thinks.
Nice boat, but.....
I thought maybe a deeper "V" and a inboard to troll with, (I have a 5 HP trolling motor hanging off the back now).
I looked at a few boats that fit my need on Craigslist here and there.
Many have Merc 140 4 bangers in them.
All seem to have cracked block or.......
1 or 2 I can think, "well they don't drain the block last winter", but an alarming amount.
Is there a problem with these motors?
If, yes, what is the cure??
Is it really a Buick 3.0 block?
From what years?
Thanks!
Joe
Getting my duck in a row for the next "project"

 

[alldodge]

Is there a problem with these motors?

Nothing wrong with the motors, only issue is folks not knowing how to winterize them. Nothing special, pretty easy, most just forget to pull the block plug and stick a wire up in the hole.

Is it really a Buick 3.0 block?

Nope, They are marine engine only and have not been used in the automotive world

 

[thumpar]

Any block will crack in the winter if it is cold enough and not drained. A neighbor of mine had a 4.3l they didn't get winterized and it cracked the block. I had a 2.5l (almost the exact same as the 3.0l) that was made in 1983 and never had an issue. I still see it on the lake every once in a while. The 3.0l was not used in a car. The 2.5l version was but only a couple years in the 60's Novas.

 

[joetheis]

I thought so, but the amount of "Cracked Blocks" or 1 I saw, read, "Block fixed a few years ago"????
I thought at first "overheat", but that is usually heads, head gaskets, burnt valves..................
Guess these are the poor unfortunate boats that lazy owners owned!
When you figure it takes what? 1/2 hour to drain, (I open my drain plugs on the ride home, let the road "shake" the water out, then pump the anti freeze in).
Too bad about this a marine engine only, I have a friend who owns a junk yard, thought maybe I'd get a block for a case of beer!
Well, this clears up a lot AND gets me to looking.........
Joe

 

[Rick Stephens]

The 3.0L is a very well made motor. I too wish it were a crossover automotive block, just in case I ever had to replace mine. The 3.0L in my boat is 25 years old, looks 4 years old and has never needed internal work. While it is getting a little tired and could use a ring and valve job, it still starts up every time and both gets me to my fishing spots where I do my trolling with a Honda outboard, and pulls my kids around on wakeboards without issue. Doesn't use any oil and the inside is as clean as if it were a new motor. Amazing well made piece of equipment you can destroy with a single cold night and a little carelessness.

I would probably not purchase a boat with a cracked 3 liter unless I already had lined up a replacement motor. The block is spendy since it is marine only sourced.

Rick

 

[joetheis]

Thanks!
I looked at some prices of NEW long blocks.
Not a "OUCH", but....
I'd have to find something that is a solid base as a project, then slip the motor in and have something that I can count on for years.
Joe

 

[biggjimm]

I had a 120 2.5L mercruiser that I bought not knowing it was cracked & thought I lucked out when my buddy was scrapping an old Chevy ll w/ the same 2.5L block in it. Come to find out it was cracked also & it was worse than my marine block. Mine was not cracked on the inside only on the outside of water jacket so I cleaned it up real good & give it the old jb weld treatment & what little water dribbled out, I just pumped out the bilge. I ran it like that for 7 seasons & the guy I sold it to has ran it for 5 & still runs it today. That's the only engine I ever rebuilt knowing it had a cracked block, ha. I caught a lot of flack over that from my car buddies but it worked & still works. Have fun & be safe. Jim.

 

[joetheis]

Yeah really, when you think about it, a boat motor doesn't run under PSI like a land cruiser, so you're just stemming the water leak.
Tell them the crack was to bleed any air outta the block!
Joe

 

[Maclin]

Where abouts are you located. Maybe there was an unseasonal low temperature stretch that caught some with their pants down and blocks full?

 

[Maclin]

And the 140's seemed to be able to limit the damage to the outside water jacket regarding the engine block on mild freezes, but they seemed also to want to pop a core plug in the most inaccessible places.

 

[joetheis]

I'm from North Eastern Pa, (By Scranton).
Yeah, we have cold here, but lets be real, it's not like your cutting grass in shorts today and shoveling snow tomorrow!
By the time "block crackin' cold" get here, only it's deer season, even duck/goose hunting is long done.
I dunno what the reason was, it was just when I looked at Craigslist, Scranton, Poconos, Allentown, Binghamton, and of course Watertown N.Y., the style boat I was looking for, (deeper "V" open cockpit, @ 20'), they all seemed to be a 140, 120 with cracked blocks heads off, etc.
I bet at least 6 boats???????????
Joe

 

[thumpar]

20' with a 3.0l is going to be a dog. Mine is a 20' with a 5.7l and would like more power.

 

[Grub54891]

When I got my 140,it was not only cracked,but all the core plugs were blown out too. Cleaned up the crack,jb weld,new brass plugs. had the motor out and back in the boat in 6 hours. Drove her and hoped for the best. Still going 3 years later. Luckily I picked up another one,120, Last fall I showed the po how to winterize it....but he did not. I happened to be there when he was not home and it was pretty darn cold out,so I pulled the drainplugs and left. This spring he calls and asked if I wanted to buy it. I ask did you winterize it? he says yes,I stop by and it was just as I left it. NO CLUE>>>>> I talked him down on price pretty good,took it home,and it's fine,except the outdrive needed re-seal. If he would have run it the drive would have blown. NO oil in the darn thing,it was all on the ground.....Some people...lol

 

[Scott Danforth]

The 3.0 is usually in an entry price point boat. Most of the buyers have never had a boat, and couldn't add windshield washer fluid to their car, much less maintain and winterize a boat. Some have moved up from an outboard that is self draining and never gave draining the block a thought. It's not an issue with the motor itself, it is an issue with the owners of these boats.

The 3.0 liter is a common industrial motor used in boats, trash pumps, and some small generators

 

[HT32BSX115]

It's not an issue with the motor itself, it is an issue with the owners of these boats.

The 3.0 liter is a common industrial motor used in boats, trash pumps, and some small generators

Absolutely right!

The 3.0L GM industrial engine was used in many different types of equipment, even forklifts etc.......AND, Like the 230/250 cu-in GM 6cyl engine, it's one of the best most reliable engines ever put in a small boat.

BUT, of course, poor (or NO) maintenance will kill any engine!

 

[joetheis]

Taking your all advice I looked at a boat with a 140 in it.
All I can say is................ "Poor Thing"!
It's like the dawgs your see chained in the back yard..........
The pics looked good, but up close, well.
The motor won't turn over, The starter clicks, I can't turn it with the Alt. belt.
No water from the drain plug though (he told me no winterization).
The only good thing on the boat was a new alt!!
I feel sorry for boats like this, a shame.
I'd like to stay 20' with a outboard or small inboard for fuel sippers.
My last one had a 5.0, great boat, but had to hang a kicker off it to keep the fuel cost down trolling all day!
Joe

 

[HT32BSX115]

No water from the drain plug though (he told me no winterization).

Yeah. Depending on what part of the country you're in, you could probably assume the block is cracked.

 

[thumpar]

The thing I don't get is that the 120/140 engines are the easiest to drain. I could have my 120 winterized and covered in less than an hour. The bigger motors have a lot more plugs and hard to get to compared to those.

 

[joetheis]

I just don't get it either??!!
You have this BIG THING sitting in your yard, that you payed $$ for, it's given you a summers worth of smiles, it isn't your first day on this planet, you KNOW in a few days, weeks it's gonna get COLD, how freakin hard is it to climb aboard, open the petcocks and let it dribble out.
You don't have to go nuts on it (like I do), but I see so many NICE boats for sale DIRT cheap, with cracked blocks.
Maybe you should have to take a test before you buy a boat? A "Common Sense Test"??
But, thanks to stupid people out there, guys like us get GREAT deals on nice boats! A motor swap, a "U" joint, a shifter cable and some belows and poof we're smilin and wavin at the guy we bought it off of as we motor by!
Joe
Take any advice I give with a can of beer er 2!

 

[Part-time]

I bought a nice 20' deck boat dirt cheap a little while back because the PO "winterized" it by filling the motor with antifreeze right up to the oil cap...