1969 evinrude 9-1/2 weak fire

[boydog]

Evinrude model 9722M (1969 model) top cylinder is firing but very weak, bottom cylinder has a strong fire, i have installed new points and condensors, set points at .020 as flywheel states. all screws are tight.
then i will either have a weak spark or no spark on top cylinder.
two questions. 1) why the weak spark with new points and condensor?
2) which set of points is for the top cylinder? hard to tell with all coils etc mounted

 

[Crosbyman]

clean the points again …. is this a new problem or a new to you motor ?

are they original coils did you redo all the electricals incl plug wires booth clips connections etc...

did you time the motor properly ?

http://www.youtube.com/watch?v=ga1Cj...ature=youtu.be

3hp ignition much like yours on a 9.5.....same basic magneto
http://www.outboard-boat-motor-repa...on 3 HP 1952-1967 Ignition System Tune-up.htm

 

[racerone]

Coil nearest front of motor is the top cylinder.

 

[racerone]

Most of these motors need new coils or replacements have already been installed.-----Are the COILS properly adjusted with respect to air gap with flywheel magnets ??----Fact for you-----The 9722 is a 1967 model !

 

[Crosbyman]

http://www.leeroysramblings.com/OMC_9.5.htm
http://www.leeroysramblings.com/johnson_magneto.htm

if you did not know which coil feeds the top plug you likely did not fully service the magneto and those coils may look ok
but may be bad... the plug wires may need replacement if you service the magneto you may aswell consider changing the plug wires if originals are still in after 52 years !! get some wire core sparkplug wires not he carbon stuff for cars.

Bike shops , lawnmowers shops some NAPA stores will have wire core plug wires ( get 4 feet ) and new plug booths

try to read the ohms value from plug booth clip to engine body ground using the proper scale you should see 4 - 8 Kohms the good coil should read about the same if made by the same manuf.

 

[kbait]

Top coil may have a pin hole on bottom arcing to ground or chafed plug wire. Also, check for lateral play in armature plate, as any slop will directly affect point gap/timing. If there is play, post back for fix. Good luck

 

[boydog]

motor is new to me, love to make old things come back to life!
switched coils, no change. still weak spark on top cylinder, ill do more of the above tests and advise, thanks guys

 

[oldboat1]

Try cleaning and resetting the points. Use some acetone or similar with a piece of thin cardboard (match cover?) to clean, soaked in acetone.

 

[racerone]

Last one I worked on had one of the plug wires cracked.------Right where it comes through a bracket and makes a sharp bend.---Spark jumped to ground there.------Worth looking at.

 

[Crosbyman]

clean and adjust timing

if you are not going to replace the wires …:doh:

remove the top plug booth …….snip half an inch …...remove the spring clip…. clean the tip repunch

btw BEFORE you do all that just for fun as previously suggested…. measure OHMS from booth clip to engine frame and report back findings

 

[Bullie]

Last one I worked on had one of the plug wires cracked.------Right where it comes through a bracket and makes a sharp bend.---Spark jumped to ground there.------Worth looking at.

^^This^^

 

[Rook66]

motor is new to me, love to make old things come back to life!
switched coils, no change. still weak spark on top cylinder, ill do more of the above tests and advise, thanks guys

Old electrical equipment won't let old motors come back to life. All that stuff that was installed when Eisenhower or Johnson was president needs to be replaced.