55 evinrude

I have a 1969 Evinrude 55 that will not start. it has spark and 135 psi compression. cleaned carbs and checked reeds, all good. It backfires when cranking over. Looking for info to trouble shoot ignition system or any ideas on what part controls timing. thanks

If by the term "Backfires", you're stating that a loud shotgun blast sound is sounding out the exhaust... that could only be caused by having the spark plug wires reversed on 2 cylinders... OR... the flywheel nut was not torqued properly and has caused the flywheel key to shear which throws the engine out of time.

Does shearing the flywheel key on these throw the timing out ??

racerone said:

Does shearing the flywheel key on these throw the timing out ??

Click to expand...

Oh, "1969"! I misread the year..... Cancel that statement.

That model has breaker points and a distributor cap under the flywheel. OK when they work, but require periodic cleaning and servicing. Yes, both can cause firing out of time. Loud backfiring out the exhaust can also be caused by loading up with unburned fuel in the exhaust when a spark finally comes along and ignites it. Whatever, you must pull the flywheel and clean and adjust everything. Points gap adjustment is critical, .009" to .010". There is a silver wire spring in there that requires cleaning and lubrication also. If neglected, it wears and the metal dust fouls everything, including the points and distributor cap. When reinstalling the flywheel, tapers must be clean and dry and you MUST use a torque wrench to tighten the nut to 70-85 foot pounds.

checked those things, wires are marked with metal tabs with #s on them, pulled flywheel and key is good.

Will check points, etc. thanks for info.

danr780 said:

Will check points, etc. thanks for info.

Click to expand...

(Point Setting Of Battery Capacitance Discharge)
( Ignition Models - 1968 thru 1972)
(Some have points - Some do not)
(Joe Reeves)


The points must be set to .010 but no wider than .010..... BUT in some instances due to a possible slight inaccurately machined crankshaft lobe or a slight offset of one set of points, a setting slightly less than .010 would be required as follows.


Whether the crankshaft has two or three lobes, when setting the points, check the setting of the points on each individual lobe by rotating the crankshaft by hand.


You may find that setting one set of points to .010 on one lobe, then turning the crankshaft to the next lobe, the gap measures .011 or .012 (too wide). This is where you would need to close that gap down to the required .010. A gap too wide can result in a ignition miss when throttle is applied.


Bottom line, pertaining to the point setting at the various lobe locations____ .010, .010, .009, is okay____ .010, .010, .011 is not!

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

thanks for info Joe, the points are at 10 thou and clean. what I need to know now is how to time rotor to flywheel. I put the tab on rotor at the flywheel key and torqued to 85 ft. lbs. is this correct?

The rotor has its own key ! -----Look for it on the bottom.---------Hopefully you did not ask too late on this $$$$$$

Thanks for help, I found problem. Locating tab on bottom of rotor was sheared off allowing rotor to float.

That certainly is unusual. I doubt any of us would have been able to guess that. Thanks for reporting back.