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Alternator damper ok??
Hey everyone, new member and I hope someone can give be some good advice. Working on a 1990 CBR1000F for my daughter's boyfriend. It has
always had a slow cranking issue and I told him I'd look at it for him. He says he has had replaced the alternator/ Rec/ Reg and I have installed a new fully charged battery. When I finally got it started it runs great and charging system works great. BUT that very strange noise and very slow cranking when trying to start. Then I found this forum and STU'S video, that's the exact noise and slow cranking I now know the problem is the alternator damper. Only problem is now that it is out it seems to be ok. Can not rotate the inner shaft just with my finger through the center as suggested or when I place it back on the alternator shaft. It may rotate just under a quarter inch then locks and will not rotate further. I was guessing it would rotate a full 360 deg. with very little resistance. Am I testing it correctly? Is the quarter inch movement than locking normal function or am I seeing a problem? Im a bit unsure to call it good because it is exactly the same as the video. Thanks for any suggestions Tim |
Reckon "shadow" will have an answer for that soon enough man.......
Since I believe he's done it and know the whole INS and outs of it. Try PM'n him |
Boy's, yes i am still around
I am pretty sure if you put the damper back onto the alternator shaft it should only turn using a fair bit of force, if it turns easily, it is no good. You can either try to re shuffle the plates inside or buy a new one. Good Luck Aussie Johnno |
Thanks for the replies: Aussie, the problem is with the Damper
placed back on the alternator shaft, It does NOT move freely. It will turn a little less than a quarter inch then lock in place and rotate no further. Is the quarter inch movement, then locking normal operation or indication of a problem? I had expected if faulty it would rotate continuiously. Just wanting to verify proper and faulty operation. Since the noise and slow cranking matches the video I had expected to find a damper easy to rotate. Am I looking for NO rotation or movement of the inner shaft? Take Care Tim |
Had a few moments to disassemble damper. thought the split washer
was a problem till I read one of Stuconz old messages and being split is normal. (neat little friction disks) and plates. Not sure if someone else has already been in this unit. Can anyone direct me as to the correct sequence of parts in the damper. Mine was springs/thick steel plate/then sequence of fiber disks and plates ending with fiber disk being last. And of course same old question, if damper can not be rotated by hand can it still be bad?? Thanks Tim |
Tim,
I cant answer your question but I did want to let you know help is on the way. Some of these guys are in different parts of the world and time zones. Really good group of group of mature Hurricane owners here! |
Sorry it took sometime to get back to you...........internet arrives in a forked stick :)
And the Boss is such a SLAVE DRIVER.....(don't tell him I said so, though.) :eek: Welcome to the Forum, from the land of the Zulu ! To try to answer your questions 1 a breakdown of the damper - http://www.mrcycles.com/fiche_sectio...1990&fveh=3020 They also have new dampers$107 complete 2 You cannot check a damper by hand. Mine felt fine by hand, but it wasn't. 3 Any movement of the damper by hand isn't right. 4 You could add another washer on the top to improve the resistance in the damper. 5 Although I have repaired mine, I'd spend the money and buy a new damper. There are other issues involved, like stretching the primary chain if you put too much pressure in the damper - it's a clutch after all, and is designed to slip SLIGHTLY under full load, to save the primary chain. 6 And the cupped washer/s are the last items to go in, just under the big circlip as I recall. Hope this helps you :) |
Thanks for the reply Shadow:
(It's early in the morning and my boss is still in bed) don't tell him that either. I proved to myself last night the damper can still be bad even if I can't turn it by hand. Took it apart, ruffed up the fiber disks and metal plates with fine sandpaper. Put a little more spring in the spring washers by bending them slightly more in the vice. Oiled them down a little and reinstalled in bike. At first it cranked as it should, first time I heard this bike do so. But after the oil pressure came up and the damper plates and disks got saturated with oil it began to slip and then went back to the way it was. Oh well, I did prove it's the problem. I had told a salvage yard yesterday I would take a used one. But I now see the wisdom of finding a new one as you suggested. I can still give them some of my hard earned cash for a used rotor. Found the top part of the case had a crack near the bolt at the two o-clock position. Saw I was making it worse just before I got the starter gear and starter clutch gear to slip together. Thats perhaps why that part of the engine is coated with oil. I know we are almost on the other side of this great globe from each other, thanks for sharing your knowledge. This is the good part of the www//helpmeimlost internet world. Take Care Tim |
I've read a dozen threads about the alternator damper, part #5 in this diagram: http://www.mrcycles.com/fiche_sectio...1990&fveh=3020 causing starting problems. From the diagram, I can see that the starter clutch, part #4, is also on the starter. Does that ever cause the starting problem? I see it's more expensive than the alternator damper.
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Hey slowpoke: In my experance, yes they can be faulty also. On other
bikes I've had,the starter clutch would at times not grip at all and the starter would rev at a much higher rpm. Maybe it is the same with this damper problem. You just hear the odd sound of the plates and disks slipping in the damper instead. |
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