Alternator stator ring plug

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rjk40
Parallel Twin
Posts: 100
Joined: Thu Dec 05, 2013 10:54 am
Location: Malabar, Florida

Alternator stator ring plug

Post by rjk40 » Sat Nov 03, 2018 1:04 pm

First of all,

I must apologize for not being more observant when disassembling the engine three years ago, and now am paying the price.

Underneath the alternator stator, a "ring plug", p/n 0400.46.040 sits against a step in the alternator case, and, supposedly, holds the stator in position relative to the rotor.

Said ring plug is chamfered on one edge, and the other edge has a step, or lip.

The question is:

Does the ring plug's chamfered edge abut the stator, or does the step/lip do so?

In putting the thing in either way, it does not seem to make a difference, since the stator is held firm by the triangular clips, and rests aither on the chamfer's high point, or on the other edge's high step point.
I would think that there must be a reason for the difference in the ring plug's edges, but I fail to see it.

If any of you gents can shed some light, I would be most thankful.

Otherwise, I shan't worry about it.

Thanks in advance.
Regards,
Confused Old man in Florida.

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Craig in France
Cagiva Elefant
Posts: 820
Joined: Tue Mar 23, 2004 3:58 pm
Location: Montpellier, France

Re: Alternator stator ring plug

Post by Craig in France » Sun Nov 04, 2018 9:16 am

Hi Rick,

Ok, I'm confused .... :)

Here's the parts book page for the early 860. I've highlighted the part with # 0400.46.040 and description Tappo per ghiera (mis-translated as "Ring plug". It should be something like ferrule cover/sealer/closer). And that ain't right.

Image

I don't see the piece that your describe as going under the stator. Where 'tis? :?

Ciao

Craig

rjk40
Parallel Twin
Posts: 100
Joined: Thu Dec 05, 2013 10:54 am
Location: Malabar, Florida

Re: Alternator stator ring plug

Post by rjk40 » Sun Nov 04, 2018 9:34 am

Hi Craig.

Oops! My bad.

I goofed on the part number. The correct number should be 0759.88.040, which changes the description to "distance piece"'; so sorry for the blunder.
The piece in question is the large ring to the lower right, in the drawing, and to the right of the rotor and stator assemblies. I hope that clarifies the correct piece.

Question, however, remains the same: since the piece has different machining on the two edges, which edge goes against (abuts) the generator stator?

Still confused...

Regards, and Craig, I owe you another lunch next time we get to France.

Richard

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Craig in France
Cagiva Elefant
Posts: 820
Joined: Tue Mar 23, 2004 3:58 pm
Location: Montpellier, France

Re: Alternator stator ring plug

Post by Craig in France » Mon Nov 05, 2018 1:05 am

Hi Rick

Got it, ta.

According to the workshop manual, the chamfered end goes towards the bearing. Ref. page 105, Montaggio del rotore magnetico dell'alternatore.

Your problem is due (again :shock: ) to the crap translation of the original Italian. What the Italian says is:

"1. Montare sull'albero motore il distanziale, il quale dovrà essere orientato con lo smusso verso il cuscinetto".

"Smusso" is then translated in the English version as 'groove'. That's wrong. It's 'chamfer'.

HTH and Keep Building :-D !

Craig

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Craig in France
Cagiva Elefant
Posts: 820
Joined: Tue Mar 23, 2004 3:58 pm
Location: Montpellier, France

Re: Alternator stator ring plug

Post by Craig in France » Mon Nov 05, 2018 1:26 am

P.s When fitting the rotor, make sure the side with the recess faces IN. Again, a not entirely accurate translation of "incameratura" into "opening" 8) ...

rjk40
Parallel Twin
Posts: 100
Joined: Thu Dec 05, 2013 10:54 am
Location: Malabar, Florida

Re: Alternator stator ring plug

Post by rjk40 » Mon Nov 05, 2018 7:40 am

Hi Craig,

Thanks so much for the info.

Since there is no bearing in the case (P/N 0759.49.400) that the alternator stator mounts into, I must conclude that the chamfered edge of the distance piece going toward the bearing in mention really means toward the center of the engine, and not outward. There are three bearings on the plate behind, (P/N 0759.49.450, "complete holter"); those are the nearest bearings to the scene, and mebbe they are the one(s) being described.

Please let me know if I am "on the same page" as you, as I'm a bit confused by them referencing "toward the bearing" instead of either "toward the center of the engine" or toward the outside of the engine".

As for mounting the rotor, there was no need to remove it, as the faces were in great shape, no damage at all. I buffed the faces with a Scotch-Brite, and they now shine like new.

BTW, wife Dawn and I will be thinking seriously about visiting her cousin in Pomas when they move back there from here, after their oldest three (triplets) are in college, and their youngest goes to middle school in Limoux (sic?). Likely two years hence. Cousin Anthony was at the lunch we had with you in the castle. When that happens, we will look you up.

Thanks again, and please let me know on the matter above.

Regards,
Richard

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Craig in France
Cagiva Elefant
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Joined: Tue Mar 23, 2004 3:58 pm
Location: Montpellier, France

Re: Alternator stator ring plug

Post by Craig in France » Tue Nov 06, 2018 1:53 am

Hi Rick,
rjk40 wrote:
Mon Nov 05, 2018 7:40 am
Since there is no bearing in the case (P/N 0759.49.400) that the alternator stator mounts into, I must conclude that the chamfered edge of the distance piece going toward the bearing in mention really means toward the center of the engine, and not outward. There are three bearings on the plate behind, (P/N 0759.49.450, "complete holder"); those are the nearest bearings to the scene, and mebbe they are the one(s) being described.
Agree. It all amounts to the same. The chamfered edge needs to face inwards (i.e. towards both the bearing in the support plate and the main bearing).
rjk40 wrote:
Mon Nov 05, 2018 7:40 am
As for mounting the rotor, there was no need to remove it, as the faces were in great shape, no damage at all. I buffed the faces with a Scotch-Brite, and they now shine like new.
It was the rotor coming loose and wrecking the key way in the crankshaft that put paid to my 860! So, from personal experience, I recommend you make sure the 'Little Darling' is well and truly fixed - both the key way and the key in good condition and fitting tight, and the nut done up tight and with Loctite. No need to rely on tab washers these days! The manual specifies 4.5Kgm = 32 lb/ft for the nut. I might be tempted to go a little higher ...

Always happy to meet up if you make it over the Pond some day!

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