1977 johnson 115 has fire wont start

[ibarookie]

hello.i just bought a 1977 johnson 115 and it has fire but wont start.i tried spraying starter fluid in the carbs and the spark plug holes but nothing happened.i pulled the flywheel and the key is ok.when i put the flywheel back on it started and ran a couple seconds and died.then it was back to just spinning over so i pulled the flywheel again and put it back on then it backfired.i checked the key and it was sil ok.the guy i bought it from said it was running when he took it of the boat 8 months ago.the only problem he had was a miss that would comeand go.he thought it might need a coil.could someone please help im ready to blow it up. thanks

 

[ezeke]

Re: 1977 johnson 115 has fire wont start

Be sure that the flywheel is retorqued to 105 Foot Pounds.

The engine needs full choke and 300 RPM to start cold. Take the air silencer cover off and watch the choke plate as you crank to be sure that they are 100% absolutely closed and stay closed until the engine fires. If they do not stay closed, move the choke solenoid in small increments until they do.

It takes a powerful, fully charged battery to fire that engine up.

If the ignition colis are discolored, cracked, misshaped or if the potting is melted, they should be replaced.

While you have the air silencer cover off, check the throttle plates to make sure that they are perfectly synchronized throughout the range of motion from fully closed at idle to horizontal at WOT. You will have to have the choke plates open to observe the throttle plates.

 

[david_r]

Re: 1977 johnson 115 has fire wont start

DO NOT spray starter fluid int he carbs to satrt it.................. if you must manually prime it use a spray bottle with pre-mix at 50:1................. starter fluid has no oil and it needs oil in the fuel for cooling and lubrication.

have you messed with the wiring or just hte flywheel?.........back firin sounds like it could be mixed up coil wires or maybe a sheared flywheel key.

ezeke also makes a good point about the choke and battery

 

[ibarookie]

Re: 1977 johnson 115 has fire wont start

i made sure the choke was closed all the way.and still nothing.i pulled the wires off one at a time so i wouldnt cross them up.i checked the key and it is still fine.it has me puzzled because i have good fire on all plugs and the starter fluid should have made it start or backfire but it didnt.it was strange that after i put the flywhel back on the first time it sarted and ran about 10 seconds and died and then it would just spin.

 

[david_r]

Re: 1977 johnson 115 has fire wont start

do you have a good blue spark that will jump a 1/4-7/16 inch gap?

did you torque the flywheel like ezeke said?.............. if not i would suspect a sheered flywheel key.

you may have some reed problems.

have you tried just a lil spritz of fuel in each cyl , by removing the plugs, to see if that will start it?

you can also take a pencil and put it in the #1 plug hole and turn it til the pencil just starts to go down............ your flywheel should have the 0 aligned with the pointer (timing mark).......... that will save you ahving to pull the flywheel again to check the key

 

[ibarookie]

Re: 1977 johnson 115 has fire wont start

i checked the timing and its on o.i put a little fuel in each plug hole and it just spins.i checked the fire and it has a good blue spark.im puzzled.

 

[ezeke]

Re: 1977 johnson 115 has fire wont start

If your choke is working properly, you won't need to inject anything.

 

[david_r]

Re: 1977 johnson 115 has fire wont start

how about a compression test?

sounds like you have good spark and obviously got fuel to the cyls now you need compression.

you may have also gas fouled the plugs.

sometimes those plugs can be tempermental........... my son ahs a dirt bike that if you flood it you may as well just replace the plug cause no matter how many times you clean it it wont fire..................... my mom also used to have a olds cutlas supreme with one of those electric quadrajets.... it developed some probs and i had to pull the plugs and clean them 3 times in one day just so it would start and run..... every time my mom killed the car and went ot restart it it flooded.. new carb time............ sorry for the ramble but i just wanted you to know strange things can happen.

 

[jriegle04]

Re: 1977 johnson 115 has fire wont start

you should also check the flywheel magnets. if one is loose, broken or out of place it could cause this problem as well. if one is out of place a little JB weld and proper spacing and you will be back in business.

 

[krogie]

Re: 1977 johnson 115 has fire wont start

it sounds like a carb problem to me , if you have done a proper spark and compression test , then i would tearcdown the carbs and see if the flout valve is sticking. sometimes you can tape on the carb biowl and loosen the valve to atleast get her to run....good luck!!!!