Re: 1977 140hp iginiton question
Well, I feel better about the fact that there are no points...I though for a while there I was missing something.
I have checked the coils (they are the same as, and transplant right off my 115 motor, and they all worked on that motor, so I can rule them out as the cause.)
I have checked all fuses and wiring for both continuity, and voltage...that is all good.
I have taken apart, cleaned and lubed (with dielectric grease) all wiring connectors and each connection on the buss strips.
The battery is fully charged, and the battery connections are clean and tight. Battery shows 12.5 volts with no load.
When running, the motor is charging the battery at + or - 15.5 volts, so the stator is working in that regard.
The two top cylinders get good, strong, consistent spark.
The bottom two cylinders get weak, intermittent spark...
So, what is the common denominator for the bottom two cylinders?
I have a manual on order, but it will not arrive for a few days, and I am hoping to work on it tomorrow.
I have the manual for the 115, and have identified that many things (coils, flywheel, prop, main wiring harness, trim and tilt, and so on...are the same.
I cannot tell if the stator is the same, as the one on my 115 has NO markings left on it that I can read.
The stator---that looks damaged---on my 140 hp has the part number 051680 on it. I found that number in the parts section of this site, listed as "obsolete", and replaced by part number 0528099.
According to the parts list, my 115 had a stator with the part number 0582016 (6A Stator).... (but as I said, I cannot verify that, as the numbers are no longer readable on that stator).
So I guess my question is....
Is a 0582016 (6A Stator) compatible with the 140 hp, non-electronic ignition, motor?
I cannot seem to find a cross reference for that part number, as to what other motors it may work on (but I may not be doing the search correctly....)
If I cannot verify that by part cross reference, what would happen if I was to hook it up and try it? What would the possible damage to other components of the ignition system be? To my admittedly limited knowledge, a stator is basically nothing but a field coil, and a bunch of windings, that produces voltage, and/or increases amperage when energized and spinning around. In other words, it is a glorified generator, correct? There is probably a rectifier somewhere that tweeks the voltage to match things up (converts it from AC to DC, if I recall)...but if there is one of those, it must be working, or the battery would not charge..and it does. There should be no voltage regulator, as the charging system is un-regulated, and is limited only by the output of the stator.
So, in theory, any stator that fits, should work, if I hook the wires up correctly. Since there are only a few wires,and they are labeled at the distribution point, that part is easy. Of course, on the stator that came off the 115, there are two wires that ran to the power packs..but since I don't have those on this non-electronic ignition system, I should be able to leave those disconnected, and taped off to prevent shorts, with no problem. )I will have to extend the wires from the stator to the distribution panel, due to slightly different configuration of the motors, but that is not a real problem).... At least it seems that way to me...am I way off base here?
If the worst that would happen is I would blow a fuse, or it just doesn't work, then I would go ahead and give it a try....but if I have a likely hood of frying some component, I don't want to do that....
Also, on the 140 motor, I have identified the following items...
The stator, and the sensors (located under the flywheel, where I thought the points should be). The wiring for the charging system. The distribution panel (at the back of the motor, near the top of the cylinders). The main in-line fuse in the wiring harness (it is good). The coils (and verified that each is wired up correctly, to the correct cylinder, via the distribution panel). There does not seem to be a power pack (at least nothing like what was on the 115 motor, which had two of them..one for each bank of cylinders, they were blue in color, and were located on opposite sides of the motor). Each had one lead from the stator connected to it, as well as a bunch of other wires running to and from other components in the ignition system, via the buss board (or distribution panel, if you prefer).
With the non-electronic system that is on the 140, the sensors act as "points", so there should be no need for a power pack, correct? The pulses from the stator (which is triggered by the shaft turning) triggers the sensors...which sends a pulse, which fires the coil (maybe augmented by the capaciter or resistor, which ever that thing is......) which makes the plugs fire. Timing is controlled by a cam, and the timing mark setting indicated on the flywheel, and marked by a pointer (which is set at the indicated timing setting labeled on the front of the air intake, and has been verified via timing light). Ignition advance is controlled off the throttle arm..more throttle= more timing advance. Since the motor starts up and runs pretty well considering that the bottom two cylinders are not firing consistently, I assume that the timing is not really the issue, and that the timing advance works, since the motor will rev (at least under minimal load.).
Since the top two cylinders are firing fine, and the bottom two are not, it is no surprise to find the bottom two plug wet with gas after trying to run the motor. I at least know I am getting fuel there...so although I plan to remove and clean the carbs at a later date, I don't think they are the problem..especially since I have a weak spark on those two cylinders. Too much or two little fuel would not account for the weak spark....so I am back to the ignition as the culprit...
The plugs have been changed out for new, proper Champion brand plugs, that are properly gapped....and verified by moving them around. When in the top two cylinders, any of the plugs work. When in the bottom two cylinders, the plugs have weak, intermittent spark.....). Moving the coils around does not change the situation. Any coil works on the upper two cylinders, no coil makes any difference when connected to the bottom two cylinders...so I have ruled out the coils as being the problem. I have also swapped the plug wires around, with the same results...top cylinders run fine with any plug wire. Bottom cylinders still run intermittently with any plug wire.
So what do I do now? Try the other stator?
And, as a sidelight...would it be possible to convert the 140 motor over to electronic ignition by moving all the ignition parts (and some wiring harness and the distribution panel) over from the 115 motor? Has anyone done this type of upgrade? Would it be just a straight transplant, or would I have to add something that is not there? Looking at it (visually), it looks like the only problem would be mounting the power packs, as there are no appropriate mounting holes for the bolts to go into to...but that could be easily worked around...
Any advice would be appreciated....and any corrections to my theory(s) would be welcome.
