1975 70 hp Johnson

[chopper_man]

Hi,i have rebuilt the carbs,replaced all 3 coil assemblies,new plugs.There is good compression in all three cylinders and they all fire.After all this work it ran great for a few weeks and now when i punch the throttle to wot position it won't punch out of the hole,seems like half throttle now.I also have the correct fuel mixture 50:1,new tank new line.Any ideas what might be causing i'm stumped and have gone thru the manual a hundred times now,i'm going crazy please help!!!<br /><br />Thanks in advance Chopper

 

[OBJ]

Re: 1975 70 hp Johnson

Sounds like your droppin' a cylinder Chopper. Losen spark on one. Quickest way I can think of to check is to take a timing light and put it on each plug wire and see if your loosen any spark at WOT.<br /><br />EDIT: You might want to go back and check the grounds on the ignition coils and power pack also. Bad ground can cause a lotta' headaches.