1974 mercury 115 has issues need help please

[bassboy416]

So.... Bought a 1973 kona skier with a 1974 mercury 1150 in line w/ trim. Boat has 2 seperate issues (at least I'm pretty sure theyre seperate). Boat has always been hard to start for the first time each outing but runs and starts fantastic once warm... last time I took it out the engine would not start... It cranked without any sputter or even trying to start... I pulled the plugs, cleaned them (Surface Gap plugs which weren't really even dirty).... I threw some premix in the spark plug holes and she started up and purred like a kitten... Is this a carb related issue? not sure... Runs great at wide open throttle and all speeds.. Idles excellent as well... Boat does great when you nail it too unless you're towing a wakeboarder then if you go WOT too quickly it will stall out... but it does not run rough whatsoever... Boat was winterized 2 years ago by a mechanic but not sure when the last carb clean was... Anyway... The second issue is the big one... When I bought it, the battery was fried... Bought a brand new marine battery but noticed that the battery cables were in poor condition (missing insulation and having electrical tape on them in spots... They look sketchy... so... it has always had a starter delay meaning that when i turn the key it clicks...... waits a second..... then engages the starter... well the last outing I was pushing the limits of how long I should crank my motor to start it and the negative cable started melting the electrical tape on it and smoking... anyway, we took it out and the delay seemed slightly worse but it ran great for about 3 hours... then in the middle of the lake we had been sitting for about 30 minutes and went to start it and the starter moved up to engage the flywheel but didn't seem to have enough power to turn the flywheel.... I tried manually starting with a cord but with no luck... got towed in.. but now it clicks... engages the bendox spring and turns the flywheel like one tooth (not even a quarter rotation and wont go). The engine is not siezed. I am a construction worker who is mechanically inclined but also not a boat mechanic and with a busy schedule... Called a shop for an estimate on a carb clean, battery cables, starter, starter solenoid, impellor and it was 1000 bucks... I've read into this and believe that it may be simple enough that I could tackle this project on my own but looking for advice... I am willing to spend the 1000 dollars but would much rather have 1000 dollars of parts than 400 in parts and 600 labor.... any help is MUCH appreciated!

 

[bassboy416]

Re: 1974 mercury 115 has issues need help please

also... battery tested at 12.3 volts after this whole outing... its sitting on a charger as we speak

 

[merc850]

Re: 1974 mercury 115 has issues need help please

When you start it do you raise the fast idle lever(little one on side of control) pump the bulb until it's hard and hold down the choke? If the starter is too slow it might need to be taken apart and cleaned and new brushes installed if needed; new brushes from dealer. The battery should have 13v at rest and at least 12 while turning over (you'd be surprized at the current needed), you should also check the choke shutters and make sure they are covering the carbs closely while cranking engine over.

 

[bassboy416]

Re: 1974 mercury 115 has issues need help please

When I start it, I either advance the throttle or pump the choke... yest the choke seems to be working... but I rarely try both... and today I brought it home and put it in a test tank... I took off the starter... noticed that several wires are in poor shape... both positive and negative battery cables, cables going from midway on motor to right under the flywheel.... but anyway took the starter off... was sticky near the bendox gear.... tested it... works fine..... threw some DW40 all up in the bendox area and reinstalled... It fired right up with no delay.... then turned it off. Out of 10 starts, twice it didn't spin flywheel... bendox gear seemed to engage the flywheel but no power to turn it... simultaneously you could hear the starter as if it was spinning on the inside of its housing.... waited 20 minutes... starts every time better than ever now.... Thinking its time for a new starter but concerned about the cables as well. Doesn't look easy to change the wires because they go into this "plug" that plugs into the side of the boat.

 

[mr 88]

Re: 1974 mercury 115 has issues need help please

These motors like to be "flooded" when cold starting. Once you squeeze the primer bulb and you think its hard ,keep priming it as your forcing more fuel into the carbs and eventually the reeds.As far as your slight hesitation on acceleration the cause of that is your idle jets,if you open each one up a 1/16 of a turn [ remember where your starting point is] then try it. If it gets better then repeat procedure,worse the go back to base point.These carbs really do not have a transistion circuit going from idle to WOT,that extra idle fuel comes into play here.I would try and replace or splice as much new wire into the system as allowed. Your solenoid MAY be the culprit or if your wire are all corroded they will not let the amperage needed get to the starter motor,volts yes,amperage no.

 

[Chris1956]

Re: 1974 mercury 115 has issues need help please

OK, Lets handle the two issues separate. Cold starting first: Pump up the primer, lift the cold start lever (or advance the throttle, whichever you have). Hold the choke button down and crank her until she fires. Feather the choke and cold start lever until she is warm.

Pumping the choke does nothing.

Second issue: I suspect your battery cables are bad. The can corrode under what looks like good insulation. They can rot out to only a few strands. When that happens, the motor will crank fine for a revolution or two, and then slow down and eventually stop. Sound familiar? You might consider replacing the motor wiring harness as well. Those wires are usually all bad by now.

 

[racerone]

Re: 1974 mercury 115 has issues need help please

Replace the battery cables before the thing catches fire !!!

 

[bassboy416]

Re: 1974 mercury 115 has issues need help please

Thank you all for your help! It does like to be flooded to start and pumping the ball past what seems hard with the addition of straight choke and advanced idle seems to be helping... I'm hoping that in time, I will find this particular boats sweet spot... Once it starts it idles and runs great... I'm going to try adjusting the idle jets as well to dial it in... Before I take it out, I am either going to splice the cables inside the tube or purchase a new wiring harness altogether.... Now there is one other thing I'm noticing thats really disheartening... The wires going to the stator are in poor shape.. There are 2 wires that go from what I'm guessing is the power head to about halfway up the motor... these you can tell were replaced because they are easy to get to... on the same screw that those wires are midway up the motor there are 2 wires that go from midway up the motor to the stator. they're so shot I was afraid to touch them they were disintegrating in my hand.... Could this be why my boat keeps eating batteries? And is pulling the flywheel and changing out the stator a job a novice mechanic can even tackle?

 

[Chris1956]

Re: 1974 mercury 115 has issues need help please

Actually, you do not need to pull the flywheel to change the stator. Set the motor to TDC. Now remove the eight 5/16" bolts that ring the flywheel nut. Remove the outer flywheel and you will see the 4 allen screws holding the stator on. Use blue locktight when installing the flywheel bolts.

You will need to splice new battery cables to the old ones, as they are part of the boat wiring harness.

 

[bassboy416]

Re: 1974 mercury 115 has issues need help please

I am going to replace the stator and splice the cables. I am also going to replace the starter as it is very simple to do and has probably been overworked. When I set the flywheel at TDC and go to remove the bolts, will it turn the flywheel when I wrench? Should I make a mark anwhere in case things get moved in the process of removing bolts... basically, I am worried about messing up the timing if I do something wrong and how to either go out of my way to prevent it or to make it easier to fix if it does happen. Blue locktite on the bolts for reinstallation and is there a torque setting I need to follow? Thank you for sharing your knowledge and experience! My family and I all thank you!

 

[racerone]

Re: 1974 mercury 115 has issues need help please

The plug in connecter on the lower cowl is nothing but a convenience item for factory / dealer when motor was new.--------There is nothing to stop you from bypassing that plug with a set of newer battery cables.--Even the smaller wires can be relocated to a terminal block.---That would do away with the iffy connections possible in the plug-in thingy.

 

[Chris1956]

Re: 1974 mercury 115 has issues need help please

Bassboy, flywheel can only go on 8 ways. So 360 degrees/ 8 ways is 45 degrees. It will be easy to tell if your timing is 45 degrees or more off. Simply stick a screwdriver into the top cylinder and set it to top dead center. Now install the flywheel so it is as close to TDC as the bolt holes allow. Real simple.....

 

[bassboy416]

Re: 1974 mercury 115 has issues need help please

UPDATE:
Phase 1 went without a hitch... I spliced the positive and negative battery cables above all of the damaged wire with brand new wire... Soldered the splice with flux core solder then painted in liquid electrical tape and wrapped in electrical tape thoroughly... Replaced wires going to trim motor as well as the ends were messed up.... Pumped the bubble past where I usually stop (I forced like three more pumps through it after it was hard), advanced the idle (mine is a button on the stick that allows me to rev in neutral), held choke and it started better than ever before... Starter purred with no hesitation and about 5-10 seconds of cranking before she fired up..... I'm not sure if it helped that I ran the motor 2 days ago and thats why it started so easy... but it sure seems like I've had some solid advice and that you all have offered valuable information... So phase one was a complete success!!!! Next, waiting for parts to do Stator, Spark Plugs, Trailer Lights, Impellor kit.... Will update on the stator and start a new thread on the impellor.... Thanks again!

 

[eggs712]

Re: 1974 mercury 115 has issues need help please

My stator had bad insulation as well, but I chose to save money and fix the wires like in this little tutorial:
http://www.sidewinder-boats. com/portal/windertalk/archive/index.php?t-4308.html

I had to add an extra space there because iboats wouldn't let me post that link for some reason.

 

[bassboy416]

Re: 1974 mercury 115 has issues need help please

Eggs 712, that is an awesome link! Thank you for sending... Even if I get a new stator, I want to try to use this method so that I have a spare and maybe to avoid a new stator altogether... My only concern is that I drained a brand new marine battery on the lake... It could have just been bad cables but I want to make sure that the stator/rectifier are charging my battery... Again boat starts and runs great right now... How would I test with a digital multimeter to see if my battery is getting charged and verify that my stator and rectifier are working?

 

[Chris1956]

Re: 1974 mercury 115 has issues need help please

Easy to test to see if charging. Put voltmeter on battery, motor off. Note reading. Start motor, and rev it to 1500RPM. You should see voltage increase if stator/rectifier are charging.

 

[canoemang]

Re: 1974 mercury 115 has issues need help please

Heres a good way to test the rectifier.

Mercury Rectifier Testing steps with pictures

also if the tach is working then the rect probably is also..

 

[bassboy416]

Re: 1974 mercury 115 has issues need help please

Great help here I wish I could give you guys something in return... Not able to run tests today but will be on it soon.... As a note, my tach has never worked since I bought it... everything else does work though as far as guages go... Got all the parts except the stator and planning on throwing it all together friday

 

[richardlee]

Re: 1974 mercury 115 has issues need help please

Interesting thread. I just got my 1974 merc 115 started again today. Two summers ago I had it running great but had it pulled to replace transom. Would not start after I had it put back on. Too busy last summer to even untarp it. I spliced battery cables purchased from Wal Mart onto existing cables and used copper tube as a splice and taped well. I think the issue was from the mercury switch but ended up hooking it back up and it started with a small shot of starting fluid. Right about almost needing to flood to start. I am having a shifting issue since I had the shift cables off. Need to figure out how to do that.

 

[bassboy416]

Re: 1974 mercury 115 has issues need help please

Basic question... I've got everything fixed except the stator... the boat starts and runs great... I have no tach and try not to rev the engine unless it is totally submerged in water (I use a test bucket that goes past the lower intake area but not over the exhaust... I get good water flow through but not as good as when the engine is in the lake).... The battery reads pretty constant 12.63 volts... boat starts and runs fantastic.... I have the manual which suggested using some sort of specialized meter to read if the stator is working.... I don't understand the manual 100 percent... can somebody help me figure out (even if I need to go buy a different meter) how to tell for sure that my battery is getting charged? The problems I have been experiencing have been slowly getting knocked out one by one and almost everything is related to bad wires in this boat... Anyway, if you're looking at this thread in the same situation.... I bought a new starter and spliced wires.... Totally fixed issue... and starting with throttle advanced, choke, and lots of primer ball pumping has made this baby a reliable running boat once again... just trying to check on starter while I've got it apart