Logo

flywheel key???

shawnfish

Regular Contributor
question, first its a 1980 (j25rcs) johnson 25hp. a mechanic told me that the flywheel key is suppose to sit right under the little notch i have pointed out in the pic, and if it was sheared off or broke that the notch where he said the key sits below would not align with the line on top of the starter with the #1 piston at top dead center. he told me i didnt need to remove the flywheel to check it if i did what he says above is true.....now the line on the starter does not point to the right number on the flywheel when its top dead center because its not running and you have to use a timing light when running for the line on the starter to align with the right number on the flywheel wich i beleive should be 34... makes sense to me but ive never had to mess with a key or timing on my motor.....any truth to it??? thanks in advance...042 (640x480).jpg
 
There is no timing adjustment for your engine pull the flywheel and install a new woodruff key (shear key) you may need to dress up the taper on the shaft for the flywheel to fit properly if the shear key sheared and the flywheel spun on the shaft. With the cd ignition as long as the wires are correct timing should be correct just make sure the flywheel nut is torqued to spec before you go to start it. 105 ft lbs for the flywheel nut (very important). If it was getting good spark and the compression is good chances are the key is sheared even a little crease in the key will give you a no start condition. To sync the carb with the timing with the engine off you can even do it with the flywheel off put it in gear and advance the throttle until the second mark on the follower cam is center of the follower roller at that point the throttle butterfly should begin to open. Line the mark up to the roller and loosen the screw on the lever for the throttle butterfly, push the roller up to the cam and tighten the screw. Then check it starts to open the throttle just as the second mark passes center of the roller. GL

thanks kim, you have told me all that a month or two back. im not trying to mess with the timing im just trying to confirm if that little notch under the fly nut is where the key sits in the shaft and if the notch is where the key is and it lines up with the timing mark on the starter at tdc that the key is not broke/sheared. ive had a puller on that fly all summer with every lube under the sun soaking on the top of the shaft and it will not break the fly loose. ive turned that puller handle so hard with both hands and a buddy holding the fly and it will not break loose, ive used peices of pipe over the puller handle for leverage and bent the puller handle......like my first post says that mechanic swears up and down if that notch under the fly nut and the mark on the starter line up at tdc that the key is fine. and with the flywheel not coming off to check the key visually im out of luck...nuts! i just thought of something....maybe i should check the plugs?????? theyre not a year old but if hes right bout the key then maybe its not getting spark....gonna go check plugs real quick....
 

one just like it, ive beat,pryed,pulled,smaked with a small sledge etc......well i may have to kick myself dead in the poop chute, i pulled my plugs and they are fouled bad and could barely see spark when i turned it over. they were probally bad last year cuz i had a hell of a time getting it started this spring then it was fine till june, took me hours to get it started and idle so i let it idle for about 35-40 mins, killed it and it started right back up. next day at the lake i killed the battery and my arm tryin to start it and thats when the flywheel came to mind and low and behold it may have been the plugs the whole time...i feel like the biggest idiot in the world, i figured it had spark the day before so it couldnt be the plugs but i bet they had just enough spark to finally get it runnin that day and then i fouled em dead trying to start it the next day...wish i had some spares to put in and try....what i was thinking not checking the plugs after i made sure it was getting gas is beyond me. stupid stupid stupid!!! well i'll find out in the morning i guess..
 
p.s. i didnt mess with the throttle advance or none of that other stuff so hopefully im goin fishin in the morning.....QL77JC4 for plugs right?
 
fresh gas and plugs, hit the starter once and fired right up......UNBELEIVABLE!!!!! oh well my buddy will be happy to get his 25 back seeings ive had it since june lol!! thanks kim...
 
Back
Top