Questionwhere to begin?..... How about that I have erratic / inconsistent spark on cylinders 1 and 4. Cylinders 2 and 3 are fine.
Engine was running fine then, began to go down hill quickly all in a period of a week. Now the engine is hard to start. nearly impossible to keep running if it does start. Will not rev up, spits and sputters, sometimes a pop is heard from the mufflers. Using My timing light I discovered I have erratic / inconsistent spark on cylinders 1 and 4, and the spark drops out completely at 2900 RPM on cylinders 1 and 4.
Cylinders 2 and 3 are fine.
I checked the plugs,2 and 3 are not fouled 1 is wet, and plug 4 is dry.
I checked the pulse generator air gap and alignment, and it is dead on. I decided to check the pulse generator coils to find a failed coil. Not knowing just how to do this check,... I simply chose to check for a grounded coil, so....
I used a ohm meter and checked for continuity on the 6 wires coming from the pulse generator cable.I only found 'audible' continuity when I touched the meter's leads to two wires, a white or Grey color wire, and a green wire. these are side by side in the 'red' connector. For what ever it means, Both these wires and only these wires, have a 'red' band crimped around each wire.
I also wonder if the spark units could be at fault instead of a pulse coil. I don't know how to check for a bad spark unit so I simply swapped the units and attempted to start the engine....to my surprise it appeared that the engine was attempting to start, and much easier so, than has been the case. .....I am wondering if I have found my problem and it is a bad spark unit.???
SO I would like to know:
that I am conducting the correct tests i should be and that I am doing so correctly?
AM I interpreting the results correctly?
Should I look for something else that I am over looking that could be at fault?
Do you think it more likely is a bad spark unit and not the pulse generator coils?
I have only a Clymer manual to go by. I am not a mechanic by trade, just a back yard fixer struggling with this my only ride her and I we have been together a long time....unfortunately she is beginning to have something every month go bad.
I enlist your help so I can get another season from her while I search for a replacement.
Thanks for you assistance Wayne! I'll share with you my results from any tests / steps you suggest.
Please know, your help is greatly appreciated!
David
10-24-07
AnswerDavid,
FOLLOWUP:
yes, your spark units may have problems due to
bad connections on a plug or fuse, possibly
a poor frame ground or wire.
Connectors can be cleaned and coated with a
good dielectric grease to prevent further corrosion.
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these electronic parts are difficult to diagnose
because they are unpredictable and affected
by so many things. Some of the older Hondas
are experiencing problems because of poor
or corroded connectors or connections.
-Start by checking the battery cables and
grounds to the frame.
-Then the fuses for clean connectors.
-Then check the connectors themselves to the
spark units and pulse coils and ignition
coils and grounds.
-The stator connectors can be troublesome (yellow wires)
-the pulser coils are usually around 500 ohms
(blue and yellow wires.)
and the ignition coils primary 3.0 ohms,
the secondary around 21000 ohms with the caps on.
-these bikes also have a mechanical ignition
advance unit under the pulse coils
that may be sticky.
-if cylinder #1 is wet, you might want to
check all the compressions.
-the pulse coils are more likely to
go but usually act up when hot
or quit altogether. Try checking the ohms cold
and hot.
-If it runs on cylinder 1 and 4 okay with
the spark unit swapped, then that is
likely the problem. Try it with the timing
light again if you can get it going.
Double check the connector plugs.
