alternator wire harness repair or replacement

[Nick]

With the clutch plates installed there's enough drag so that you can blast the nut on or off without any 'clutch-holding' tools, or other gizmos. There's also a lock washer and, if you're really worried, Loctite. Takes all of 10 minutes to remove the clutch.

Can't resist a few words on the excellence of the Ducati clutch. I've put a fair amount of miles on my Ducs and have never once had to do any work to a clutch. Compared to the clutches produced by the Brits during the same era, the Duc's is in another league altogether.

[Magman]

[quote="DewCatTea-Bob"][quote= Magman ...
" I may pick up a clutch holding tool or Make one from an old clutch disk. "

"____ Is that because you haven't understood how locking-up the drive-sprocket & transmission could hold the clutch-hub & nut from turning, for you ? "

I understand the principle behind the block of wood wedged against the case. I have an old urethane handle screwdriver with deep teeth marks from removing a Harley clutch with a dual row primary chain using this wedge lock method. My thinking was that I will be removing the clutch from the engine on the bench and wont have the luxury of using the transmission to dump some of the load into the transmission gears and tire. Since I would be concentrating and transferring all of the load into a local area of the bottom of the engine case, there is some possible risk of cracking the case. The rag wedge method would eliminate that risk. The other concern was the order or removal for the hub vs flywheel. This order would not be an issue (for whatever reason) if I had a clutch holding tool. Correct? So, I reason the tool has good value, especially on the bench. I have the engine on the bench now and I have other frame questions related to front end removal and swing arm removal to post in a seperate subject.

"With a 4th-wire added,, there's then two-pairs of alt.stator wire-leads, one pair for each alt.power-coil so that access to each power-output can then be done separately (for a charging-system which can take advantage of COMPLETELY electrically-separated alt.power-outputs). "

OK, that makes good sense to add the 4th wire. I will do that. I will need some direction on the process when I get to that point of reassembly. I can research it but if you know of a good thread with pics etc., please add a link. I am really enjoying working on the bike. I pulled the frame up off the engine and set aside. I picked up the engine that was surprisingly light and put it on the bench. FUN STUFF

[Magman]

With the clutch plates installed there's enough drag so that you can blast the nut on or off without any 'clutch-holding' tools, or other gizmos..

Sanity check_ Are all the nuts/bolts inside the left engine case right hand thread except for the Alt nut on the crank which is left hand thread?

I have a 1/2" drive air impact gun and 100+ lb shop air so I don't want to crank ther wrong way. :/

[DewCatTea-Bob]

Are all the nuts/bolts inside the left engine case right hand thread except for the Alt nut on the crank which is left hand thread? "

____ There are ONLY four threaded-parts (within OHC.motors) with left-hand threads ! ...
And those LH.threaded-parts are the camshaft & crankshaft and their two (identical) nuts, found ONLY on just the right-side of the engine !


Dukaddy-DUKEs,
-Bob

[DewCatTea-Bob]

[quote="Magman"]
" I understand the principle behind the block of wood wedged against the case.
Since I would be concentrating and transferring all of the load into a local area of the bottom of the engine case, there is some possible risk of cracking the case. "

____ Never-mind, as I had not realized that you had access to air-powered tools, (which means that Nick's idea ought work for you). _ I don't know how extra stressful such power-wrenching could possibly be against the floor of the motor-case, but I'm fairly sure that the wood would give-way before any case-cracking could develop.
However rather with the use of good-old hand-tool wrenching, the nuts will fairly easily torque-loose long before such concern for the case is any real worry, especially with the trans in top-gear.



" that makes good sense to add the 4th wire. "

____ Right,, as not-only can any differing rectifier & regulator setups be employed, but also,, it's then possible to straight-forwardly combine the two stator-windings' power-outputs rather in parallel (instead of 'series', as most commonly-done), which then yields a 75% reduction of the total alt.stator-resistance, and thus-then able to allow more of the generated alt.power to rather be consumable more-so by the actual load-system (instead of so-much by the alt.stator-windings themselves) !
__ Also,, depending-on the chosen load-system (being matched-with the alt.power/charging-system), the use of a regulator-circuit could*be just as well done without, (* although the lack of a 4th-wire really doesn't preclude such possibility, of-course).



" I will need some direction on the process when I get to that point of reassembly. "

____ For now, I suggest that you start thinking about searching for red-wire & yellow-wire and-also same with colored-stripes, in either 16 or 18 gauge* good-quality copper (or silver).
(* 'gauge' only refers to just the thickness of the actual conducting-wire itself, and the insulation-jacket/coating over the conductor can vary the chosen wire's overall thickness,, so it's possible that four-lengths of 16-gauge [with thicker coating] could be too fat to fit-through your chosen cable-conduit. _ So it ought be most preferable to choose 16-gauge with rather thin insulation,, or-else rather choose to employ just one-pair of 16-gauge and one-pair of 18-gauge, [which would then make having one pair with colored-striping, unnecessary].)



" I am really enjoying working on the bike.
FUN STUFF "

____ YES, working on DUKEs was always a fun past-time for myself as well ! _ In-fact as I grew older, I actually preferred to do-so even more-so than riding them.


Duke-Cheers,
DCT-Bob

[Magman]

____ For now, I suggest that you start thinking about searching for red-wire & yellow-wire and-also same with colored-stripes, in either 16 or 18 gauge* good-quality copper (or silver). So it ought be most preferable to choose 16-gauge with rather thin insulation,, or-else rather choose to employ just one-pair of 16-gauge and one-pair of 18-gauge, [which would then make having one pair with colored-striping, unnecessary].)
DCT-Bob

Thanks for getting back. I was tied up all weekend selling an experimental aircraft to a fellow that flew in from Ca. It was a great weekend and I sold the plane. I use alot of aircraft wire wich is of very high quality Tefzel coating and high grade copper. Unlike most wire coatings, Tefzel does not generate poisonous gas when burned and is impervious to most chemicals and resisitent to high temp. The coating is also very thin and light. It is available in red and yellow and some other basic colors and a few stripe colors from http://www.aircraftspruce.com in many gauges including 16 gauge. Question- Would I want 2 red wires and 2 yellow wires? I can make one pair red stripe/yellow stripe and have 4 different colors?

Best-Steve

[DewCatTea-Bob]

[quote= Magman ...
" I use alot of aircraft wire wich is of very high quality Tefzel coating and high grade copper.
The coating is also very thin "

____ Seems to be the ideal wire most desired. _ It also ought-to contain a greater number of individual conducting-strands, compared to average wire (of the same gauge).
With insulation-coating on the thinner-side, you ought-to be able to get-by with all four wire-leads being 16-gauge.



" It is available in red and yellow
and a few stripe colors
Would I want 2 red wires and 2 yellow wires? I can make one pair red stripe/yellow stripe and have 4 different colors? "

____ Even-though I-myself don't happen to agree with the particular colors chosen by Ducati for their alt.wire-leads, it's rather considered best to still keep with their original/stock wire-colors. _ And accordingly of-course, also connect those same colors to their original connection-locations on the alt.stator, pretty-much just as factory-stock, (although the factory common-connection shall be undone).
However when there's more than one wire with the very-same color & size, then there's no quick & easy way to tell which wire is connected to which alt.power-coil. _ So in order to remain with all stock wire-coloring and yet still be able to distinguish the individual wire-leads, it's then best to have the two-pairs of wire-leads colored as: 1 solid-yellow & 1 solid-red, and 1 yellow-striped & 1 red-striped, (just as you've realized would appropriately differ your four wire-colors).
The actual color of the colored-striping wouldn't really matter much,, but in order to avoid any related confusion, either yellow or red striping ought-to be avoided, and the stripe-color ought preferably be the same for both striped wires.
____ I'm somewhat pleased that you seem willing to make your-own alt.cable (as opposed to installing an acceptably suitable preexisting wire-cable of some sort).
I suspect you'll find some self-satisfaction, (if not outright pleasure) in constructing your very-own alt.cable, (just as I-myself have, [at-least by the time it's been completed] !).
__ After you've also chosen your preference of conduit-encasement/hosing for your alt.cable,, please ask for advice-tips, if you have any concerns fitting your two-pairs of wire-leads through it.


Hopeful-Cheers,
-Bob

[djstedman]

Magman and Bob-

So this is my first post, but just wanted to chime in on the alternator work on these old ducatis. I have been reading up on the posts located here and have decided to do just as Bob has stated as it seemed like the most logical approach(i.e. to add the forth wire to the 3 wire stators)

Just as a little background

I have a 66' ducati with a 3 wire alternator and the wires were shot coming out of the primary. So I decided to replace the wires (or so I thought that was the plan). So after removing the stator I took some measurement on the coils and determined the lighting coil was bad.

28W stator.jpg

28W stator2.jpg

" that makes good sense to add the 4th wire. "

____ Right,, as not-only can any differing rectifier & regulator setups be employed, but also,, it's then possible to straight-forwardly combine the two stator-windings' power-outputs rather in parallel (instead of 'series', as most commonly-done), which then yields a 75% reduction of the total alt.stator-resistance, and thus-then able to allow more of the generated alt.power to rather be consumable more-so by the actual load-system (instead of so-much by the alt.stator-windings themselves) !
__ Also,, depending-on the chosen load-system (being matched-with the alt.power/charging-system), the use of a regulator-circuit could*be just as well done without, (* although the lack of a 4th-wire really doesn't preclude such possibility, of-course).

So I have completed the modification with a replacement coil (will rewind original coil in the future) and will be wiring up a custom wiring harness next. I just wanted to show what the finished product can look like. The original coil [Ignition coil] is ~.75ohm and the replacement coil [lighting coil] is ~.8ohm. I used 16AWG PTFE wire since I am familiar with it's properties and like the quality of this particular type of wire.

4 wire stator.jpg

[DewCatTea-Bob]

[quote= djstedman ...
" So this is my first post, but just wanted to chime in on the alternator work on these old ducatis. "

____ Thanks much for that ! _ And of-course your (somewhat fairly related) post is more than welcome, however yours would've been considerably more logically at-home within this-other thread... viewtopic.php?f=3&t=1566&start=10#p11582 , since your n-c.type 28w-alt.stator is the same as the 160's (and has next to nothing in common with the w-c.type alt.stator of THIS thread) !



" I have been reading up on the posts located here and have decided to do just as Bob has stated as it seemed like the most logical approach(i.e. to add the forth wire to the 3 wire stators) "

____ Indeed ! _ However THIS 4th-wire mod is a considerably different situation, and only one of your (4-pole) alt.power-coils can now be full-wave rectified (if so desired).
__ What is your intention to do with the ign.power-coil, now that you've got it ungrounded ?



" So after removing the stator I took some measurement on the coils and determined the lighting coil was bad. "

____ The lighting-winding shares it's coil-core with the bat.charging-winding... so exactly how did you specifically determine that the lighting-winding was "bad" ?



" So I have completed the modification with a replacement coil
The original coil [Ignition coil] is ~.75ohm and the replacement coil [lighting coil] is ~.8ohm. "

____ I'm not too clear on this... as both of your stated ohm-figures indicate only that of ign.power-coil ohmic-values.
__ From where did you get your replacement power-coil / "[lighting coil]" from ?



" I just wanted to show what the finished product can look like. "

____ Thanks for that ! _ Looks like very-good/quality work !
It'd be quite nice if you could possibly offer that work done for others who'd rather afford to have you do such for them, instead of attempting such finished-quality on their-own.



" I used 16AWG PTFE wire "

____ What wire-colors were you able to choose for your intended circuit hook-ups ?


Duke-Cheers,
-Bob

[djstedman]

however yours would've been considerably more logically at-home within this-other thread... viewtopic.php?f=3&t=1566&start=10#p11582

Yeah, co-location of like material is important, learning about these different model alternators can be quite the blur without a concise spec sheet for each one.

___ Indeed ! _ However THIS 4th-wire mod is a considerably different situation, and only one of your (4-pole) alt.power-coils can now be full-wave rectified (if so desired).
__ What is your intention to do with the ign.power-coil, now that you've got it ungrounded ?

Not sure I understand what your saying, I though if you had both ends of a coil, your AC (or pulsed DC) could be full-wave rectified. I was planning to do this with both coils individually then combining the positive voltages after the rectifiers. I still haven't thought it completely out.. Here is what I do know: I have a shorai 6V large AH battery, a DC COIL
#32. 01.06, an after market headlight maintaining the 25W/25W bulb (looks like a older scrambler type with a 3 position switch),I also will be using a custom LED tail light. I will be putting together a schematic soon. Any feedback up to this point would be certainly welcome.

" So after removing the stator I took some measurement on the coils and determined the lighting coil was bad. "
____ The lighting-winding shares it's coil-core with the bat.charging-winding... so exactly how did you specifically determine that the lighting-winding was "bad" ?

from the thread you pointed to viewtopic.php?f=3&t=1566&start=10#p11582 it states the red/white(.7ohms and .3ohms respectively) I measured (.25ohms and .08ohms respectively) nearly the same values the O.P. of that thread (common failure point?)

" So I have completed the modification with a replacement coil
The original coil [Ignition coil] is ~.75ohm and the replacement coil [lighting coil] is ~.8ohm. "

____ I'm not too clear on this... as both of your stated ohm-figures indicate only that of ign.power-coil ohmic-values.
__ From where did you get your replacement power-coil / "[lighting coil]" from ?

I purchase a NOS ducati coil, it most likely is an ignition coil for a slightly different model. I do not have the #'s here in front of me, but I believe the #'s I purchase corresponded to Italian #'s for ignition coil on the motocross model. (not sure) I just know the form factor works and the coil is approximately the same resistance as the ignition coil. My intention was to run two approximately even powered coils to power the entire system. I'm not using stock parts so attempting to "balance the loads" is not something I want to try. If my alternator cannot put out enough juice to keep the system happy I will have to turn off the headlight so the excess can then charge the battery back up. This is all an experiment!

" I used 16AWG PTFE wire "
____ What wire-colors were you able to choose for your intended circuit hook-ups ?

What was available at the electronics house I picked up my wire from. (white with blue stripe and white with red stripe for the ignition coil for the power coil I used Green with yellow stripe and a grey with white stripe) All future operator/owners will not be able to determine what they have from the factory ducati schematics alone, but the rest of the bike won't match a ducati schematic either!


Doug