1978 115 hp johnson

[camo15ok]

The past few times on the lake my boat has been bogging down and only running on two cylinders, i would remove the cowling hit the power pack and the other two would engage and i would be home free the rest of the day, however my powepack smacking days are over now, i tried this trick again the last time out and nothing would happen. I have now replaced the power pack, the motor seems to run better using the muffs, So back to the lake, i tried again last night under pressure same problem, boat will not plane out it feels like the two cylinders get kicked on then off again over and over. . Do you guys think this could be a coil issue? I am going to get out the light gun tonight and see if i see anything irregular.

thanks for your suggestions up front

 

[emdsapmgr]

Re: 1978 115 hp johnson

Usually the coils on that engine are pretty reliable. That engine has two idential power packs. One controls the spark to each head. You can swap them for testing purposes. If the no spark problem moves from one head to another after the swap, replace the bad pack.

 

[camo15ok]

Re: 1978 115 hp johnson

i have replaced the power pack, however the boat still seems to be having issues, I have also checked the grounds. Is it possible the power pack i recieved is faulty, i bought the pack from Sierra and it is supposed to be a direct OEM replacement for my motor. The boat tries to get on plane but the two cylinders cut on and off from the left side. I also checked the plugs last night, they were a little wet but nothing to bad.

Thanks
Cameron

 

[camo15ok]

Re: 1978 115 hp johnson

New power pack installed, but still bad spark on new power pack side. I can switch the power packs and the bad spark will follow the new power pack. Not sure where to look next any help would be great.

 

[boobie]

Re: 1978 115 hp johnson

It wouldn't be the first time somebody got a bad new power pack. Call the supplier and talk to them.