New Member 93 ST1100 - 28A Alternator getting REWIND - Anyone Else??

[JustDave]

Hello to ALL! New Member 2018-09-22 from Texas. Am getting my newly-purchased $1000 (yup, $1K with just 38K well-cared-for Miles) 1993 ST1100's 28-Ampere Alternator STATOR rewound at a Shop with Experience and a Good Reputation. Any OTHER MEMBERS have a 28A Alternator/Stator lying around who want to get in on this??? >>>Likely cheaper if we get multiple Rewind Jobs into this Shop.<<< Am able to 'double-check' this Shop's personnel/experience/materials-used... since my 2nd-ever-Job was at Reliable Electric Motor (a big operation)... rebuilding fractional motors (learned every-thing), while i went to EE College. Let me know guys / gals... P.S. - once my 1ST-Post gets approved... will be providing some Details re the infamous MolyPaste, and current sources/prices... and Wiring Diagrams/Info re Reliabilty ISSUES/weak Design points observed... and Details learned from my Alternator Re-Assembly, and SwingArm/DriveShaft Re-Assembly (that Honda Manual statement re "leave the Moly60 off of one spline to allow air to escape" intrigues me). Have a Blessed, and SAFE, Day! -JustDave

 

[John OoSTerhuis]

Interesting, Dave. FirST I’ve heard in 20 years on the forums of a successful rewind/rebuild of a 28amp stator. How much did it coST and how many miles on your rebuild? TIA

Removing the moly GREASE (3%, not 40% paste, RTM) in one groove on the drive shaft is to let air escape when inserted into the Driveshaft Joint. Moly grease is also spec’d for the Driveshaft Joint and Pinion Joint splines. BTDTx3

John

 

[JustDave]

Hello John O! Thanks for the RTM pointer; read it again. Cost of 28A rewind yet to be determined; waiting on email replys from (now) 3 Shops. >>>>> Still procuring Honda Parts, Moly 'lubes', and gold-plated connectors (rated at 90A) to replace the 3P Connector. Due here 'soon'. Also found some "1,650-tinned-copper-strands" 8GA "flexible" silicone-jacketed 220degreesC-rated wire; may replace the Honda 3-wire 'cable' from rear of Stator, after getting a good look at the OEM wires et al. --David --P.S. attached for y'all's Viewing Pleasure are captioned Photos of one man's Handmade 'Pancake' Generator ... for a slightly different application than our ST1n00s. AND, the last photo is my "Target" for my 28A.

 

[wjbertrand]

I recall a few attempts in the past to have these re-wound by specialty shops, I think one company (Electro sport or some such) was offering the service. In all the cases I've heard about the repair was very short-lived or failed to work out of the box. About that time it was discovered that the '96 and later factory 40A alternator could be retrofitted and the subject of repairing the 28A was not explored further as I recall.

This is a topic that could become popular again, particularly if successful, as parts supplies for ST1100s of all years begin to dry up.

 

[JustDave]

Well, bikers and bikerettes... i have some MORE info to throw into this 28A Topic: "Honda Engine-Oil Pumped To Rotor". While waiting for my various Parts Orders to arrive, have been RE-reading my Honda 1991-1993 Shop Manual (Issued April 1992). Page 4-2 shows an oil-path Diagram. *The following is a loooong chain of descriptions of what is in the Diagram; not easy to follow to the end. >>>>> Looks to me like OIL gets pumped... through "oil orifice" (Callout Item 7 on p4-3)... through a "gallary" (sic)... TO the forward small bearing on the 28A rotor-assembly shaft (where that bearing slides into the recess in rear of engine)... and through a hollow in that shaft... to the Driven-Gears (infamous split-gears)... and 2-piece 'flywheel' (springs inside), both shown on p. 17-10 (*NOTE the notches in forward part of flywheel assembly; see attached) ... and to the big bearing (sits in aluminum casting that bolts to the rear of engine)..... AND diagram appears to show a tiny hole into the REAR portion of the Rotor shaft (the section on which the actual cup-shaped ROTOR sits)... which section shows to be hollow(! or maybe a drilled gallery?)... with tiny arrows showing oil going into the rotor-body(!)... and, oil shown going through the shaft TO the small bearing at rear (which fits into a recess in the Stator-housing)... with NO return-path for the oil shown! >>>>> Now, IF y'all followed along (looking at the same p4-2 Diagram) --- Mr. Honda appears to be purposely pumping metered amounts of (hot) engine-oil, all-the-way to the rear bearing. IF oil gets past that bearing, it would also get past it's rear recess fit, in the Stator-housing... sooner-or-later. [WHY we have 28A Failures over time??] >>>>> Comments are welcomed...

 

[John OoSTerhuis]

Not sure I understand what you’re getting at. The 28amper is oil cooled vs the 40amper which is air cooled. Yes, engine oil gets to the rear bearing and drains back through the Alternator Shaft Assembly to the crankcase. And yes, the insides of the stator are continuously bathed in oil. This design is widely used on many bikes.

Edit: what’s the source of your picture and who wrote the text in it?

John

 

[Bush]

what’s the source of your picture and who wrote the text in it?

Obviously someone who didn't know squat, judging by the comment "we all expected that space was dry by design".

 

[wjbertrand]

Not sure I understand what you’re getting at. The 28amper is oil cooled vs the 40amper which is air cooled. Yes, engine oil gets to the rear bearing and drains back through the Alternator Shaft Assembly to the crankcase. And yes, the insides of the stator are continuously bathed in oil. This design is widely used on many bikes.

Edit: what’s the source of your picture and who wrote the text in it?

John

John is exactly correct. That’s why there’s a big-assed o-ring where the housing fits to the crank case.


Sent from my iPhone using Tapatalk Pro

 

[Bush]

That’s why there’s a big-assed o-ring

Ha Ha! Looks like the automated bad word censor has relaxed a bit!

 

[kiltman]

I just received the 40 amp alternator today from North Carolina. It was $136 US plus $15 shipping. I ordered it Oct. 1st.