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1998 Johnson 90hp how to remove timing wheel

G

gone_postal

Regular Contributor
"J90ELECM

I believe my stat

"J90ELECM

I believe my stator is on its way out. The motor stranded me a few weeks ago and the next time I took it out it stalled several times at idle and once at full speed - just sputtered and died. My tach also stopped going over 1500rpm (new tach, new reg/rect, rebuilt motor).

Anyway, I have factory service manual and turned motor to 30*, but I don't have piston stop tool that it references to thread into cyl-1. Is this absolutely necessary? Could I have someone hold a screwdriver? Or could I use a bolt? What length should it be and what is the thread/pitch of spark plug hole?

Also, in which way does the nut on timing wheel remove? I'm assuming it's reverse thread b/c that's the only thing that makes sense - piston stop tool would prevent motor from tuning any further, but it is a VERY tight bolt - tried having someone hold wheel w/ hands and I can't break its seal w/out turning motor any - definitely don't want my timing off.

This sucks!! It's beautiful out and I want to be boating!!!"
 
"an impact gun would be ideal

"an impact gun would be ideal for that nut,its not rev thread.you can try to jam the flywheel,i dont reccomend it ,things can break if not careful,try to locate a strap wrench,timeing is controlled by the timer base as long as you dont mess with the linkage involved it should not be a problem,/put it back the same way as it was .."
 
"This is what I don't unde

"This is what I don't understand:

If I insert piston stop, I'm assuming I adjust it to contact piston at the 30* mark that manual references. So, if it's reverse thread, that would make sense b/c as I try to turn clockwise, the motor can't turn b/c cyl 1 is against the stop and it'd break seal on the timing bolt.

If it's indeed NOT reverse, then turning ccw would just back the piston away from the stop - what the hell is the point of the stop??

I only ask b/c in the manual it shows the guy using a breaker bar, so I'm expecting some force to have to be used. I do have an impact, so I'll give that a shot. I just don't want to order the stop if it's not necessary - OMC one is $50!! I found several on Summit for less than $10 that will do the job and will probably end up ordering one anyway."
 
"either way you turn the pisto

"either way you turn the piston will hit and stop,where ever the stop is set.in reference to timing wheel you mean fly wheel?dont bother with
the stoppper jam it and be careful,or try the strap wrench,"
 
"The piston stop is for checki

"The piston stop is for checking the tdc pointer, not for reefing against to loosen the flywheel. You thread it in a certain amount, mark where the piston hits while holding it counter-clockwise against it. Then turn it all the way clockwise till you hit again. Mark the flywheel again. The point exactly in between those two marks is where the tdc pointer should be pointing.

You need a strap wrench or something to hold the flywheel while you crank on the nut. Using a piston stop to hold the motor in place is going to break something expensive.....like the top of the piston or the spark plug threads.

If you really feel the need to jam a piston to get the nut off, move the piston about halfway down the bore, then pack the bore with clothsline or something that will put an even force across the entire piston and head. I've never done it. I've always found a way to hold the flywheel or crankshaft. Even a block of wood between the prop and cavitation plate will suffice if it's not too tight."
 
"Okay, I was referencing the n

"Okay, I was referencing the nut that holds the timing wheel on - this motor is the optical timing style. I used my impact gun on it and the bolt came right out. (have no idea why manual tells you to put piston stop in before doing this, but I managed without)

I now have the entire timing cover off and can see the flywheel. I do not have the flywheel jamming tool. Once again I used my impact and removed the 5 bolts holding the flywheel in. Now I have to pull the flywheel, but once again it references another tool I don't have. Looks like a basic puller - two bolts thread into flywheel and a 3rd center bolt you crank down on and that pushes the flywheel out. Looks like I'm gonna have to order this - the flywheel kit is $60 - not sure what else I can use to remove it though - I don't want to damage anything. Anyone know if Autozone rents something similar I could use?

Finally, the flywheel bolts - are they a grade 8 bolt? I'm looking to get them locally from Ace rather than order them and have to wait. I just don't want to risk buying the wrong thing

Any suggestions?"
 
"yes its called a steering wh

"yes its called a steering wheel puller ,you will
need some threaded rods from the hdware store,to make it work. talk to the guys at the zone they shoul point you in the right direction.
you can buy one for like 20.00 bucks"
 
"Yeah, I saw that tool, but en

"Yeah, I saw that tool, but ended up renting a harmonic balancer puller - came w/ several bolts, etc. It worked like a charm.

I was disappointed to see my stator looked great though - actually better (shinier) than my used spare that has been sitting in a box for a few years (probably for obvious reasons - like use). I decided to pull it anyway to take some pictures to get opinions of people on this site and to my surprise, it was stuck to the block!! Yup, it had melted some underneath - where I couldn't see. So, hopefully my spare will get me through the season and I can pony up for a new one later (just spent $160 on the timing tool for the optical sensor and $70 on thermostats & flywheel bolts, but hopefully now I can tackle all jobs the motor needs myself!!)"
 
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