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\\ update\\ johnson 50 h.p. sherred flywheel key ? overheat

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bill murrin

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replaced head gasket..."blown out" around edges...but still had 135 lbs compression , now @ 142 on both cyl's.....and runs cool again !!!
REPLACED new factory flywheel key.....my timing was at 19*( wot)....now idles @ 4*(btdc)...at wot only goes to 8*.......can move advance by hand, but will only go to 8*,with adj. screw turned completely out. using dial indicator on #1 cyl. , dial out to 19* , flywheel showes it @ 8* btdc.......question : how can the timing change by just replacing the flywheel key ????...need to know how to advance timing ? ? ? ?
 
The timing is controlled by magnets in the flywheel !!-----------And by rotation of the timer base / sensor coils.
 
Use a timing light hooked up to cyl 1.
If adjusting when cranking and WOT timing, set timing about 4 less than stated.
Idle timing is of no importance, but pick-up timing is. (when carbs starts to open).
A factory workshop manual may save you a lot of mistakes and money.
 
Full spark advance timing must be checked with throttle set at full throttle, with timer base rotated all the way against the rubber stop of the timing advance stop screw.

The flywheel key must be installed so that the flat outer edge of the key is vertical with the engine, straight up and down, NOT aligned with the crankshaft taper. The flywheel nut must be torqued to 105 foot pounds, otherwise the key will shear.

What year is that engine? Model number?
 
Key is fine( flywheel ) ....starts up, but really backfires when giving engine throttle, then stalls out........( back to nuteral) starts up , and begines to backfire again
 
If this "backfire" noise is a loud shotgun like noise actually firing out the exhaust section of the engine, then yes, the engine is backfiring. This can only happen if the engine is out of time or an ignition wire is crossed somewhere.

If however, this "backfiring" is really just a noise generated by the engine spitting back thru the face of the carburetor(s), then no, the engine is not actually backfiring but rather is simply running lean due to a fouled carburetor(s) or some other reason that is causing the engine to run lean...... normally a carburetor problem.

This "spitting back" condition can also be caused by having the throttle butterflies opening too soon in relation to the timing. Throttle butterflies should "all" open and close at the same time.... and must just start to open when the scribe mark on the cam is aligned dead center with the throttle roller, not before or after.

Either of these conditions will result in the engine dying out when throttle is applied.

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay auction at:

http://shop.ebay.com/Joe_OMC32/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1
 
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still barking....with timing light on #1 cyl., small backfire , seen in timing light.
removed flywheel, the charging coil had a small meltdown.......stator coils like new, trigger coil looks fine also
still cant set the timing passed 8*
have sharp spark, blue, jumping 1/2 "
starts cold , runs fine........untill warmed up......starts backfiring untill it makes a loud backfire then stops.
note: new head gasket, 142 psi (both cyl's) , new flywheel key..........any ideas ???
 
Yes, you could tell us if that engine is firing out the exhaust port like a shotgun blast or not.

If not, I'd suspect fouled carburetors that is causing a lean mixture.
 
i have never seen carb's so clean !!.......engine pops/sputters/gags/ then" boom"....and...
still goes wot with key off!!! once in a while......"maybe a simple unbolt and drop in charlotte harbor".....i'll keep kick'in it around........:mad:
 
with timing light on #1..idle...4* b.t.d.c. then it starts poping ......the charging coil had a small melt spot in the rear of the coil, and driped down to the base plate....could this coil be the problem when it warms up and starts poping ? ?
 
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