1978 Mercury 115 starting help

[bazzmaster]

What can I do to get this old beast to start easier??? Has newer plugs/wires, cleaned carbs... I just get tired of playing with the choke and idle lever and cranking for 5 minutes to get it to start for the first time of the day......starts fine after that..... whatever "THUNDERBOLT IGNITION" means I am guessing that technology is 30 years old and not helping this old motor now.....Any suggestions are appreciated....

 

[Laddies]

Re: 1978 Mercury 115 starting help

Those 115s are very cold blooded so the idle could be lean and they are also very hard to start if you have low battery voltage hook a voltmeter to the white post starboard side of the switchbox if voltage drops to less the 9 1/2 to 10 volts when cranking, hook it on a fast charger and try to start it, if it starts you need to find the source of the low voltage

 

[Scaaty]

Re: 1978 Mercury 115 starting help

Try putting a new primer bulb in the fuel line. A good one, not Walmart. And pump it hard as ya can. They are cold blooded, and that gas needs a boost at crank speed to get way up there.

 

[jimg984]

Re: 1978 Mercury 115 starting help

good luck i have the same problem with1987 115hp only has a choke on 2 of the 3 carbs some eng had brain fade on this design make sure the choke assembly is working
other wise a very good engine if not worn out

 

[daveswaves]

Re: 1978 Mercury 115 starting help

Heres a trick I use on my 75 1150. Pump the bulb up hard, tilt the engine up all the way and then back down again, yup the fuel spills over when you tilt it up and then runs into the crankcase when you put it down. I added power tilt on mine so up/down and away we go.

 

[Scaaty]

Re: 1978 Mercury 115 starting help

Heres a trick I use on my 75 1150. Pump the bulb up hard, tilt the engine up all the way and then back down again, yup the fuel spills over when you tilt it up and then runs into the crankcase when you put it down. I added power tilt on mine so up/down and away we go.

Yep, YA GOTTA flood it! That will work fine.
Do it with the (for a check) cover off, motor tilted, and pump the bulb. When gas flows out the carbs, lay her down and go for an instant ride.
Just put together a crank up 135 72 rebuild for my 15 Flatbottom. A BEAR to start, but SHE LIKES GAS!
Rebuilding the carb float/neddles probably the worst thing ya can do...hard to over power them with the bulb.
There is an electric pump "Primer" off an Evinrude that can also be hooked up, but, thats something my Merc Guru knows about.
Do the tilt and pump...then try it..(and keep timing at 21 degrees, and run MidGrade gas.. )
Hope this helps..