1971 Johnny 50 starter problems

[Jconnell43]

Trying to start my Johnson 50 in a tub and I notice that the starter gear will not stay engaged and that the flywheel then seems to run in the opposite direction for a split second afterwards.
What is going on here?
Many thanks,
Jim

 

[boobie]

You need some tuning on the motor. Once it fires it doesn't want to keep running and the starter kicks out to early.

 

[Jconnell43]

That's where I'm stuck.
Everything else is looking good, only thing left to play with is the timing but I thought that adjusted itself at idle?

 

[jbuote]

​You've done head gasket, so compression is good now right? lol
Yes.. Once WOT timing is set, idle timing pretty much takes care of itself (As far as I know anyway...)

​Just a thought...
​Have you checked the flywheel key?
If the key is sheared, then timing is off, so it might kick backwards., (I think it would anyway... )

​Could verify if TDC of top cylinder..
​Get top cylinder to the top of it's stroke (closest to the spark plug hole. Use a pencil, or better a TDC gauge)
​Does the timing pointer on the block point to TDC on the flywheel?

​Then, maybe follow this first..
​(Skip the spark gap tester part)

http://forums.iboats.com/forum/engi...4008-joe-reeves-wot-timing-procedure?t=228183

If neither of the above work, maybe pull flywheel and check key?

​Again, just a thought...

​For whatever it's worth... lol
​

 

[Jconnell43]

Will do all of the above and reply.
So when the top cylinder is closest to the spark hole even if I do this by turning the flywheel manually then the pointer should be at TDC.
I can't get it running so I will have to do this manually

 

[jbuote]

Yeah.. Take spark plugs out, turn flywheel by hand till top cylinder is at it's highest point. (closest to spark plug hole). Then TDC mark on flywheel should be at the pointer on the block.
​If not, then key MIGHT be sheared..

​Still new myself, but that's how I found out my key was sheared on my 71 50hp... (My TDC was nowhere near the pointer with #1 cyl at highest point)

​If pointer lines up to TDC on flywheel with top cylinder at highest point, then key is probably good, so then I'd probably try the Joe Reeves timing method I linked to, and see if that helps..

​That was my thought anyway... lol

 

[Jconnell43]

Just checked flywheel and TDC per above.
Consistently about 90 degs off.
Will rent puller from autozone and figure out how to make a strap wrench

 

[Jconnell43]

No Title

Jbuote nailed it,many thanks, pulled flywheel and key had crumbled, have OE Johnson one on the way.

When I rotate the crank and get the top cyl at TDC the slot in the crank is facing backwards, it looks like when I put the flywheel back on that the pointer will be pointing at TDC so that looks good.

While I do have a generic manual it covers many years and is hard to use, nothing like this friendly forum.

While I'm here is there anything else I should do like sand the magnets or grease something?
Any tips on getting key in correctly when it arrives?

Thanks to all who helped!

 

[jbuote]

While it's open, maybe make sure the timer base moves freely? doesn't hang up?. Make sure there's no oozing from the stator coils...
Not sure about sanding the magnets or anything else right now, but ​I'm sure the more experienced here have some great tips on that and other things worth checking..

​Just make sure tapers have a good mating surface, not pitted, scored etc...
​I used Prussian blue to check mine, but whatever works for you.. lol

​You can use valve lapping compound to get a better fit if needed..

Also, be sure there is nothing on the tapers when installing again.. clean, dry, degreased, no lube etc..
​You want the key installed so the flat face of it is parallel to the crankshaft..
​I think F_R shared a pic of the key installation somewhere here.. I can look for it, but maybe he or someone can post that pic here for you.. :noidea:

​If you use something on the threads like anti-seizes or Loctite, just make sure it doesn't get on the tapers.. lol...