06 1800 - Alternator Noise and Replacement

[dadiam]

I have an '06 with 74K miles. Late last year, I started to notice a bit of an irregular rattle (kind of) or knock when the bike was cold/warming up and idling. It seems to fade as the bike warms up and the RPMs go higher. I got very determined last night to find the source, and after poking around and listening with a steel rod, I found the sound was coming from the alternator, specifically the brush-end (away from the engine). I could even feel the alternator shake and vibrate while running. Listening to other areas on the engine and tranny, and the areas around the alternator, including the mounting area, I could not hear anything, so I am hoping that it is not the ADG. The closer to the end with the brushes I listened, the louder the noise was, and the easier I could feel the rattle. When I got it out (I did NOT have to remove the engine or any Tupperware except the side panel) the splines looked like new. I could spin the shaft with no binding, and it seemed smooth and easy. No rattles when I shook it, and the shaft was tight with no movement except of course, to turn. Hoping it's the alternator bushing/bearing.

I absent-mindedly started the engine with the alternator out, and quickly realized the error...it pumps a LOT of oil!

I am hoping a new alternator will remedy before I spend the $$$ for an ADG. Does anyone have any suggestions on the type of alternator to buy? I HATE spending $800+ on an OEM. I can get a CompuFire for $300 less. Worked great on my 1500. Are the after markets any good? Anything or any brands to watch out for?

[Viking]

I would suggest taking it to a rebuild shop, and have them change the bearings and diodes while they are in doing the brushes. The OEM alternator is probably the best quality you are going to get, and the shop can decide if there is something bent in there causing the vibration. It's winter right now, so you have time. Specially where you live.

[dadiam]

Thank you - I decided tonight to get a used alternator tomorrow to use until I get the old one rebuilt. Cheaper, keep an OEM, and also a spare for way cheaper then a new one. Just hopes this fixes it!

[dadiam]

We've had a heat wave here in Minnesota, and I rode twice in January, and every day this past week in February. Just need to watch out for the sand in the corners. We are planning some long trips in early spring, so I'm trying to be proactive.