Mercury Boating - Popular Questions, Answers, Tips & Manuals

That serial number was produced during the years of 1988 through 1990.

Mercury Boating | 123 views | 0 helpful votes

Take out the spark plug. Hold a drinking straw up to the spray nozzle and shoot the fog into the spark plug hole.

Mercury Boating | 133 views | 0 helpful votes

Depends on the HP of the motor. The long shaft will only ad a few lbs. See this link for motor specs on weights.

Mercury Boating | 124 views | 0 helpful votes

Best not to do it as you will get maybe 2 mph. Also, I believe it is ******* to modify 1996 and later motors.

Mercury Boating | 137 views | 0 helpful votes

Check the fuel filter for blockage and check the plugs for spark. If no spark, you could have bad coils. Here is a video on how to go through the checks.

Mercury Boating | 211 views | 0 helpful votes

Any outboard 2 cycle after 1965 will run on 50:1 approx 500ml or half a quart per 5 gallon tank.

Mercury Boating | 139 views | 1 helpful votes

Sounds like the gas isn't flowing freely into the carb. Check to see if the gas lines are open, no obstructions. Also check the gas tank, I there is a screen on the gas inlet tube and that might be plugged.

Mercury Boating | 166 views | 0 helpful votes

(Carburetor Adjustment - Single S/S Adjustable Needle Valve)

Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.

Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

Note: As a final double check setting of the slow speed valve(s), if the engine has more than one carburetor, do not attempt to gradually adjust all of the valves/carburetors at the same time. Do one at a time until you hit the above response (die out or spit back), then go on to the next valve/carburetor. It may be necessary to back out "all" of the slow speed adjustable needle valves 1/8 turn before doing this final adjustment due to the fact that one of the valves might be initially set ever so slightly lean.

Mercury Boating | 141 views | 0 helpful votes

Product Line Year H.P. Model Number Model Description MERCURY 1978 115 1115628 MERC 115

Mercury Boating | 152 views | 0 helpful votes

There are some universal ones available, but I just stick my 9hp outboard in a bucket of water and flush that way.

Mercury Boating | 152 views | 0 helpful votes

what you are trying to say is that the engine wont rev up? or it revs up fine with no load but cant rev up when trying to push the boat? maybe its still running on 5 cylinders

Mercury Boating | 127 views | 0 helpful votes

I got this free Pdf manual from an online store for free and I don't think Ive visited a mechanic or fixya for help for more than 3-4 times out of the all the times I fixed the chipper in these 4 years

Mercury Boating | 148 views | 0 helpful votes

When checking the compression on an outboard motor... you aren't looking for the final number as much as the percentages of variation. There are so many things that can vary the compression numbers, like throttle position, air temperature, and even the tilt of the motor on a four stroke, that the manufacturers don't put the numbers out. What you are looking for is less than 10% variation between all cylinders. So if 3 cylinders are giving you 120 psi and the forth cylinder is giving you 105 psi, that hole has a problem. In the old 2 stroke days what we would find is people were using air cooled 2 stoke oil, which has a much higher burn temperature, and fouling the piston rings with tar.

Mercury Boating | 278 views | 0 helpful votes

If the serial number is 3065967, it is a 1971.
(Not 80659677??)
It appears that the last year produced was 1976 with serial numbers starting with 4314385.
8 and 3 misreading is not uncommon.

Mercury Boating | 251 views | 0 helpful votes

Possibly a bad bearing in the tilt motor? Try disconnecting the motor from the tilt mechanism if possible then operate the motor. If it makes noise but less of it, it will be because it is no longer under load. Good luck.

Mercury Boating | 200 views | 0 helpful votes

Check the actual model and serial number with Mercury. If newer it’s possibly a four stroke. If it’s an older motor it’s more likely to be a two stroke.

Mercury Boating | 180 views | 1 helpful votes

Only things I could find ...
  1. S/N beginning with 8075603 , 2.2 Hp was 1984
  2. There was a different reference that different countries could have different serial number series which complicates matters.
  3. But there was also a reference indicating for outboard motors ... that the nameplate which has the model and serial number ALSO had the year written down ... the last 2 digits of the year in a box in the lower right hand corner

Mercury Boating | 137 views | 1 helpful votes

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