1985 Mercury 115 inline 6 " Need Your Advice" " HELP "

STIK GUITAR

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Im looking at a 1985 Mercury 115 inline 6 to purchase. It is a fresh water engine very clean. $ 1000.00 I just need your input on these old engines Good or Bad. Expensive replacement parts or not. 125 compression on all cylinders Thanks
 

AMD Rules

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Sep 23, 2004
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Re: 1985 Mercury 115 inline 6 " Need Your Advice" " HELP "

Provided it has been well cared for, and is funtioning properly.... they are a great motor. The 115 you refer to specifically is one of the best Merc stacks built. Known to be a good performer.

The V6 motors tend to have a bit more acceleration, but price wise you won't see much difference from a spare parts perspective.

Hard to kick the tires over the net, but street value would typically be hovering above 1K for that motor in good condition. Value depends a lot on geographical location, and supply/demand etc...

If you can test drive it, do so. If not you're gonna be stuck with a compresison/spark check and an inspection of the gearcase lube, wiring, and overall visual condition as a best guess.

Toss a coin and cross your toes.
 

STIK GUITAR

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Re: 1985 Mercury 115 inline 6 " Need Your Advice" " HELP "

A small marine shop owner has this engine he is going to change the water pump and make sure it is running correctly He is very trust worthy He also has another engine just like it Low 110 compression on one cylinder 125 on the other 5 for 300.00 $ Should i buy it for spare parts
 

Scaaty

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Re: 1985 Mercury 115 inline 6 " Need Your Advice" " HELP "

Look if YOU DON"T BUY BOTH MOTORS..I WILL!
Do it ..love those old inlines..just make DAMN sure its linked and synced (in the FAQ Forom as a sticky). Run no more than 21 degrees timing, and mid grade fuel..
 

Texasmark

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Re: 1985 Mercury 115 inline 6 " Need Your Advice" " HELP "

I ran a '89 115 for 7 years and only changed the plugs once and replaced the water jacket cover over the heads due to a small water leak. Great engine.

Mark
 

quebec#1

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Re: 1985 Mercury 115 inline 6 " Need Your Advice" " HELP "

I just bought a cvx 16 with a 1985 merc 115. It runs real well ! The previous owner jsut had the water jacket done in July and the impeller and stator.
Compression is about 120 to the lowest at 114 on all 6 .
No oil injection to worry about !
http://www.youtube.com/watch?v=djnDQKKl8FA
 

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BF

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Re: 1985 Mercury 115 inline 6 " Need Your Advice" " HELP "

Hey Quebec... nice vid. I don't mean to hijack the thread, but want to find out more about your boat. What is max hp for the boat? What is your max mph with the 115? What prop you spinnin'?

I have the same boat... but it's not a glastron. It was made by a small company who bought some hulls from Glastron, and then finished the boats themselves. The rating plate has been missing from ours for as long as we've had it, I suspect because it has a V6 150 on it. The previous owner said it had a 115 for the first 2 years, then he upgraded. I suspect he (or the dealer) removed the plate if/when they put a motor on the boat larger than it was rated for.

Anyway the lower unit on my 150 went south this summer, so we've got the winter to either fix/replace that or repower.

Thx.
 

Chris1956

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Joined
Mar 25, 2004
Messages
27,036
Re: 1985 Mercury 115 inline 6 " Need Your Advice" " HELP "

Stik, I owned a '77 Merc 1500 inline six for 20+ years(1979-2007). It was a good motor, although the 150HP model was a bit high strung, since it was a maximum HP version of the 99Cu in block. It always ran good, but took some know how to run great.

I just bought a '93 135HP V6 for $1K. It has a lot more low end power than my inline ever did. It also has more top end than my inline had in the last 10 years. The drawdack is that the V6 is 100# heavier than the inline.

Considering that you will have a hard time finding anyone to work on that inline (too old for most shops), and the superior design of the V6 motor, I recommend you shop around for a newer V6.

BTW - The V6s used alot of common parts in the 135-200HP motors of the same displacement(2.0L). Parts are therefore readily available.
 

quebec#1

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Re: 1985 Mercury 115 inline 6 " Need Your Advice" " HELP "

Hey Quebec... nice vid. I don't mean to hijack the thread, but want to find out more about your boat. What is max hp for the boat? What is your max mph with the 115? What prop you spinnin'?

I have the same boat... but it's not a glastron. It was made by a small company who bought some hulls from Glastron, and then finished the boats themselves. The rating plate has been missing from ours for as long as we've had it, I suspect because it has a V6 150 on it. The previous owner said it had a 115 for the first 2 years, then he upgraded. I suspect he (or the dealer) removed the plate if/when they put a motor on the boat larger than it was rated for.

Anyway the lower unit on my 150 went south this summer, so we've got the winter to either fix/replace that or repower.

Thx.
The max thats rated for the boat is 125 hp. I just bought the boat but i tried a 19 aluminum prop that came with boat that has a chunk of a fin missing and it ran about 55 mph. Much better out of the hole as well. The other prop is a 23 pitch aluminum, thats way too much pitch for the engine and boat, max speed 52 mph. I just bought a used laser 2 20 pitch sst that i will try in the spring i think i should get her to 57 mph.
 

BF

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Re: 1985 Mercury 115 inline 6 " Need Your Advice" " HELP "

thx for the info... We've only spun a 19" aluminum prop on our boat. It's fast fast out of the hole and pulls skiers etc well, but tops out in the low 50's. I think our motor is mounted too low too. At max speed the chine walking gets a bit whacky. Your boat looks to be more stable than mine at speed.

Thanks again.
 

quebec#1

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Re: 1985 Mercury 115 inline 6 " Need Your Advice" " HELP "

thx for the info... We've only spun a 19" aluminum prop on our boat. It's fast fast out of the hole and pulls skiers etc well, but tops out in the low 50's. I think our motor is mounted too low too. At max speed the chine walking gets a bit whacky. Your boat looks to be more stable than mine at speed.

Thanks again.

Is your boat based on the GT 150 ?
I had plastic fixed trim tabs on The Gt and that made a world of difference.
I bought some metal ones but sold the boat and they look like they wont fit the CVX.
 

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croSSed

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Re: 1985 Mercury 115 inline 6 " Need Your Advice" " HELP "

The max thats rated for the boat is 125 hp. I just bought the boat but i tried a 19 aluminum prop that came with boat that has a chunk of a fin missing and it ran about 55 mph. Much better out of the hole as well. The other prop is a 23 pitch aluminum, thats way too much pitch for the engine and boat, max speed 52 mph. I just bought a used laser 2 20 pitch sst that i will try in the spring i think i should get her to 57 mph.

If you get a chance try a 22p Laser II. I have both a 20p and 22p. My boat is similar to your Carlson (mine's a Cee Bee Avenger Mach II). My 20p Laser II I use for skiing. At wot it turns nearly 6000 rpm! With the 22p the boat is faster by about 3 mph and the motor turns a more "sane" 5600-5800 rpm. Top speed using gps and a greatly stipped load was about 57 mph.

TG
 

croSSed

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Messages
249
Re: 1985 Mercury 115 inline 6 " Need Your Advice" " HELP "

I just bought a cvx 16 with a 1985 merc 115. It runs real well ! The previous owner jsut had the water jacket done in July and the impeller and stator.
Compression is about 120 to the lowest at 114 on all 6 .
No oil injection to worry about !
http://www.youtube.com/watch?v=djnDQKKl8FA

Cool video. Reminds me a lot of my ride. Same motor, similar boat. Did your speedo say you were doing over 65? Keep in mind that those pitot type speedos are notoriously bad at measuring actual speed. My speedo says I'm doing 65 at absolute top speed as well. GPS says I'm doing 57. I'll believe the gps.
Be safe out there!

TG
 

BF

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Re: 1985 Mercury 115 inline 6 " Need Your Advice" " HELP "

Is your boat based on the GT 150 ?
I had plastic fixed trim tabs on The Gt and that made a world of difference.
I bought some metal ones but sold the boat and they look like they wont fit the CVX.


Hi again... nope, mine is just like your CVX... Just got a "swiftsure" badge on it. We've had it a long time (87 or so?) and I've never made much effort to maximize the performance... we were always more interested in it's ability to pull slalom than it's top end. certainly I'd think it should do a bit better if it had a 21" SS prop, and the motor lifted a hole or two. The smart tabs would be good too. Also my hull doesn't like to plane at a slow speed, and if you trim up to sharpen the wake for wakeboarding or kneeboarding, it tends to porpoise. Now that we're pulling small kids in tubes, it'd be nice if it planed slow without having the bow in the air. Smart tabs would probably fix that. But... with the lower unit broken and the floor getting soft (maybe stringers too?), it's either time for a major overhaul, or to just move on.
 

DWFS

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Re: 1985 Mercury 115 inline 6 " Need Your Advice" " HELP "

The max thats rated for the boat is 125 hp. I just bought the boat but i tried a 19 aluminum prop that came with boat that has a chunk of a fin missing and it ran about 55 mph. Much better out of the hole as well. The other prop is a 23 pitch aluminum, thats way too much pitch for the engine and boat, max speed 52 mph. I just bought a used laser 2 20 pitch sst that i will try in the spring i think i should get her to 57 mph.
I have the glastron version, inclosed tank, 5 seater, Approc 17' 5" long with a 115 merc stack 6. The max sticker plate reads a max hp of 140.
 
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