All my work with RPM's has been guessing and for me to do an accurate tune up I need to come up with a tach and just not sure what to buy for a marine 2 cylinder '72 50 hp Johnson with non-points ignition .
Thank You for the help!
I had a response with a link to a post that said you can time your engine,
Mine is a ('72 50hp Johnson), by removing the plugs and cranking the motor while at full throttle and IF your target is 19 Degree's you set it at 15.
Sounds too simple but worth a try. If it really works it would beat...
'72 Johnson Anniversary Special 50hp
The service manual simply doesn't say anything, at least that I saw. It says take it over 3500 RPMS and adjust to 19 deg BTDC
Now my thoughts are telling me that 3500 RPMS at no load is not the same as under load.... And thus my boat runs slower and surges...
72 50 HP Johnson
Timed at 3 deg at no load idle, with load about 4 deg at 750 rpms and 19 degree's at WOT
Appears to have a loss of spunk on take off and instead or seeing 32mph I'm barely able to get 25...
Could one of the carbs be not opening all the way, woul dthat cause something like...
My thought was that I needed to disconnect the positive wire from the battery and test the current between the lead and the battery? But after looking at it I'm not so sure that will show me anything.
I have not received my OMC service manual yet and thought you guys might be able to help. I am wanting to know how the fuel lines should be connected on this old motor ?
I currently have them connected
Line 1 - Fuel pump outlet in to the upper carb bottom supply connection.
Line 2 - Carb to...
Points are not listed for this engine online, is it points ignition? I felt certain it was but now I'm wondering. Would like to know before I remove the flywheel and start something unnecessary just for a Spring tune up.
Timmie's in the well Lassie, go for help !
New carb kits, but the service manual I bought does not mention how many turns out to begin adjusting?
It's also a HydroElectric Shift with the 5 wire shift switch and I would like to find a replacement shift switch. It's the one with the roller.