New to me Mariner 115 with oddball S/N 5794485 ?

[Bossmanbig]

I just purchased a small cruiser boat with a Mariner 115 6 Cyl motor on the back. Guy said it won't start, but when I search the S/N on all the sites it never comes up with any results. I want to see if I can fix this beast up and get on the water, but I can't find any info on it.

I'd love some assistance in pushing me off on the quest..

S/N 5794485 attched to a mid 80's 14' Avenger

 

[racerone]

Look again.-----I found the parts listing in just seconds.----Why you say " oddball "

 

[Chris1956]

Gee, a 14 foot Avenger with a 115HP motor? My 16 foot Avenger is listed as 85 HP max.

I would recommend caution as they can chinewalk.

 

[Mohawkmtrs]

With Mercury and Mariner outboards, you have to lookup serial number ranges.

Your Mariner 115 6-cylinder (serial #5794485) falls in the range of 5600967 - 6436122.

 

[Bossmanbig]

Yeah, honestly it's way too much power for what I want. I really just want to get it running, so I can sell it and buy a smaller motor. I'm using this boat for a fishing boat that my wife can come and lounge around with me...she's not a fan of the aluminum Jon boat seats haha!

So in that S/N range, they're all the same? Soooo I have a 2 stroke 6 cyl that needs premixed fuel? 20:1?

Are there service manuals around for these? What year(s) would this fall into?


Thanks for the help fellas

 

[Mohawkmtrs]

Basically, yes they're all the same...some were extra- or long shaft, short shaft, some with power trim/tilt, some no PTT. All were electric start.

Fuel/oil ratio is 50:1.

Service manuals can likely be had from a Mercury/Mariner Dealer or e-bay, etc.

Years of manufacture is 1980 - 1981.

 

[Bossmanbig]

Great! Thank you! That'll get me going at least.
I did see the parts manual with the S/N ranges, but that didn't give any of the basic info of the motor. The seller said it was a 4 stroke....luckily he sold the whole thing for cheap so I won't get too mad at him.

 

[jimmbo]

The seller said it was a 4 stroke....:

Hmm, I hope that clown didn't run it on straight gasoline.

 

[racerone]

Some of those came with that " auto blend " set-up.-------And there are those folks who know that if you don't have to mix gas and oil then the motor " must be a 4 stroke "------My opinion-----Some folks know more details about their cellphones then they know about fine machinery.

 

[jimmbo]

I remember the AutoBlend, but it wasn't introduced until 1986 or 87. It was an educational tool for studying Lift to Drag ratio when it was given the mighty Heave Ho

 

[Bossmanbig]

So I got it running. Sounds smooth, however it seems to run too fast.
it will not start, however; without starter fluid being spayed into each carb. Once it starts it seems to run fine.
I just dropped it off at a marine engine mechanic that says these motors have controler issues and tend to start burning up the electronics. He said he'd look at it and do all the standard checks (compression, carb, ignition etc.) and tell me what to expect.
Are these in the category of not worth fixing?
Ultimately, it's too much motor for my boat so I'd like to sell it and get a smaller one. But I'm not the kind of person who sells crap to people knowing it's just junk....but if it's worth repairing I'm comfortable explaining the issues to the new owners and letting them decide....

 

[racerone]

Explain your starting procedure.----Sounds like it might not be according to the book.

 

[Bossmanbig]

I squeeze the bulb until I feel pressure (usually 2 full squeezes) then attempt to start. No start, shot of starter fluid in each of the carbs, stats right up.

 

[merc850]

Are you using the choke or enrichener at start up? If not this could explain your problem.

 

[racerone]

Raise the fast idle lever.-----Push key in WHILE cranking it over.

 

[Bossmanbig]

Are these things supposed to be on the shifter/throttle? I don't see them accessible on the motor itself (on the outside of the cover at least)
I haven't noticed that the key can "push in".

 

[Bossmanbig]

Shoot, I thought I posted the results of the inspection....this is from the mechanic:

The 115hp Mariner has 150psi on all 6cylinders. Spark is present on all cylinders. Electric choke works, synch and link have normal movement. The motor has a fuel starvation issue. This issue can be caused by a number of things: carburation, tank, bulb hose and connectors, reed valve, fuel pump, etec...lower unit needs to be serviced. Gear oil is muddy old but no sign of water intrusion. My quote to repair this motor here if fuel system and lower unit service brings the motor back to live is $600. Keep in mind, ignition may not work the way it looks. Spark can jump or go out anytime due to its age. Water can leak thru exhaust plate and base gaskets causes motor not to run right even with sufficient fuel and spark. The inspection fee is $60.
The 1975 15hp Evinrude has 120psi per cylinder. Spark plugs tell its history of running good. Lower unit needs service, $120. If the the motor fires and runs cool, no carb work needed. If carb repair needed and water jack must be replaced to bypass thermostat. The total cost will be $350. If head powerhead gaskets needed due to its age, another $250 will be added. Otherwise, this motor has good potential of running good but is only worth 350-400 in the market. Combined inspection and get discount at $40. Total inspection cost $100 for both motors. Let me know when you will pick them up. Thanks

 

[racerone]

Not sure I understand what you want here.

 

[Bossmanbig]

That was the text I got from the mechanic....I forgot to edit out the part about the second motor.

Good compression, good spark, fuel starved...won't start without a shot of ether into the carbs, but then it runs when it starts

 

[Chris1956]

Choke the snot out of the motor to cold start. Most MerControls have a small lever that can raise to advance the throttle for cold start. You should also have a push button for choke on the control, or the key should push in to choke.

Pump the primer up until hard, raise the cold start lever, hold the choke in on position and crank her until she starts.