1976 Johnson 85 only has 25% power

[Javlin85]

My local mechanic (part changer) told me that my boat had no power because the timing base was bad. Timing base has been replaced and wired correctly thanks to JB(thanks again). It has new plugs, new gas, new carb kits. Motor starts easily. Idles fine until I try to open it up. After about half throttle it falls on its face. It doesn't die, but when I bring the throttle back to idle position the motor idles at about 2200rmp. Pumping the bulb on the tank does not help during full throttle or during high idle. To me it sounds like the carbs, but I've been clear through them 3 times. Please help if you've seen this before.<br /><br />Thanks

 

[Big Four]

Re: 1976 Johnson 85 only has 25% power

The sync and link on the carb/igintion timing needs set up. Take it back to the moron that did the work and ask him if he's capable of doing the sync and link. It's super critical on 2 strokes that the ingintion timing be advanced at the right rate as the carbs open. Almost sounds like he left the timing cam rolled off when he put it back together. Whatever you do don't be shifting that engine at 2200rpms, or you'll be buying gearcase next.

 

[Javlin85]

Re: 1976 Johnson 85 only has 25% power

I have to choke it to bring the R's down low enough to get it in gear to put it on the trailor.<br /><br /><br />hmmmm....so that's what the crunching sound was.

 

[Javlin85]

Re: 1976 Johnson 85 only has 25% power

Well Big Four....you were right. Maggot motors had screwed up the sync and link. I bought a new timer base, a new startor, a new power pack, new plugs, new carb kits, and a fly wheel shear key just to find out that I'm a complete idiot!! The timing advance was connected to the throttle linkage, but the adjuster screw was about 1 1/2 inchs out from where it should have been. When I took the stick to WOT the timing would advance to the stop, but the throttle would only be opened up about half way.<br /><br />This is an expensive "I told you so" isn't it JB?<br />Live and learn. And to all you other novices out there, listen to these guys on this board or take you boat to a PRO!<br /> <br /><br />Thanks again guys!

 

[Big Four]

Re: 1976 Johnson 85 only has 25% power

Did you at least get the old parts to keep for spares??

 

[Javlin85]

Re: 1976 Johnson 85 only has 25% power

I was SOOOOOOOO confident about the sync and link fixing the problem. It made perfect sense! Only getting partial throttle only give partial power, but the bad news is the motor still doesn't run right. The motor runs great at idle and WOT in the tank, but under a load it still falls on its face. (sigh) For what it's worth I tested the ohms from the spark plug wire to the orange coil wire on the power pack and the two coils on the left as you look at the back of the motor were 25-26 ohms. The coil on the top right was open, no ohms, and the bottom right had 9 ohms. <br /><br />I'm through making assumptions about this motor. I'm gonna take it in and pay a good mech $80 HR to fix it. If I don't I'll be bald from pulling my hair out.