1993 Mariner 115

[MamaRenbarger]

Bought a smoker craft with a Mariner 115 4cylinder, 2 stroke on July 1. Previous owner had it in storage for 4 years, did not run it the last year.

First time on the water fired up and ran, from half to full throttle nothing there, won’t open up anything above roughly 2200 rpm. Took it to a family friend who adjusted carbs and changed impeller.

Fast forward two weeks, took it out, still won’t open up but now chugs and then stalls when trying to put it in gear.

We have read so much and watched so many YouTube videos and asked anyone who may know we’re just lost. Any marina or boat mechanic is weeks out so not much help to us. We also have had trouble with the control box and continuous beeping that seems to be a dead end when we follow any codes.

We would appreciate any help, husband is not new to boats but I am. Thank you!

 

[flyingscott]

You MUST get a factory manual for that motor. It is known as a 2+2 motor because it idles on the top 2 cylinders and the bottom 2 come in at 1800 rpm. Your carbs sound like they need to be properly cleaned and a link and sync done. How old is the gas? Is there oil in the injection tank on the motor? The 2+2 operation works like this only the top 2 cylinders have idle circuits in the carb. The 2 bottom carbs have only tiny little holes to provide enough lube for the cylinders but not enough to fire. The bottom 2 carbs also have accelerator pumps on them to help transition to running on 4 cylinders at 1800 rpm. I cannot stress enough to get the correct FACTORY MANUAL FOR YOUR MOTOR. Youtube will not help you on this motor. Or take it to a mechanic one who is familiar with those motors.

 

[MamaRenbarger]

Thanks for the response! I’ll see if I can find a manual for it, I assume I can find one online. We have run two entire tanks of high grade gas through it, so fresh, also ran sea foam through it. Assuming the oil tank is the (injection) tank, yes.

 

[flyingscott]

Yes The oil tank is the injection tank. It could have a bad sensor, the factory manual will help you with all that, NO SELOC OR CLYMER MANUALS,

 

[Texasmark]

ebay: https://www.ebay.com/itm/Mercury-Ou...vice-manual-/301890818178?hash=item464a185082

 

[roscoe]

Ok, I have to ask.

You obviously have an engine with a problem, or 2.
Why would you run 2 tanks of fuel through it, risking serious damage or catastrophic failure?

If your car only went 15 miles an hour, would you continue driving it with the gas pedal smashed to the floor?

Has anyone actually checked the motor vitals, like spark, compression, or fuel delivery to the cylinders?

 

[Chris1956]

Mercury motors have a high speed stator winding. If it goes bad, the engine will not reach 2000RPM or higher. You might ohm out your stator.

 

[MamaRenbarger]

Roscoe- at first since it had been sitting for 4 years and had been fogged, all of our boat knowledgeable friends said to run it and it should clear out and it’s just gunk. We took to an uncle who used to run a marina, he “adjusted the carbs” changed the impeller and charged us an arm and a leg for the actual problem to not be resolved. It now will open up when on muffs but in the water won’t do so.

From my understanding they have checked all of those things.

 

[flyingscott]

Opening up on muffs means nothing at all. I don't think I would take advice from your boat "knowledgeable" friends. The advice they gave you is a good way to wreck a motor. Get the manual or find a mechanic who is familiar with that engine.