| Author | Message | ||
     Lanretsr |
Two questions, I'm taking apart my primary after a strange noise after the xb9 reduction swap. I noticed a blueing around my starter ring. I'm guessing it from from heat. But was is always there from when it was installed or is it from the clutch slipping. More importantly how much crank shaft end play should there be? I'm a little worried since I can push and pull the crank and see and hear it move about 1/16 of an inch.. maybe less. When I'm looking at the crank with the stator cover off it looks like its two pieces. There the oil seal, a large metal bearing and the crankshaft through the center of that. It seems kind of weird to me that the crankshaft can move inside this spacer or bearing. Any one have any experience with this? http://good-times.webshots.com/photo/2202216500071760604lFMwjE?vhost=good-times (Message edited by lanretsr on June 27, 2008) | ||
| Akbuell |
Interesting. A quick browse of my '08 SM doesn't seem to list a figure for crankshaft end play. Didn't see anything in the photos that looked out of place. Can you get more accurate figures, like w/a caliper? As is, 1/16in is .060 thou, and w/the roller bearings the crank rides on, that may not be excessive. | ||
| Lanretsr |
it was actually .064 with the front primary pulley on it was less, but when I took it off there was about .064 I could move the primary shaft in and out and hit it hit inside the case vis the side to side play. | ||
| Fx1200 |
There should be no apparent play at the crankshaft bearing. The clearance should be around .0005 to .001 and that would be barely detectable by pushing and pulling the sprocket spline. Try putting a dial indicator on and see what the play is. .060 is way too much and would call for a bearing replacement. If the primary chain was overtightened the bearing will be severely loaded and the wear rate will be astronomical, that could also account for the bluing near the starter ring gear. | ||
| Lanretsr |
hmmm, I don't get it. I'm almost positive that the primary shaft had no play when I put the new gear on like 2 weeks ago and if anything the chain was lose. Also how would the chain being to tight cause the blueing on the starter ring. The teeth on the clutch basket so no signs of overheating and it wasn't rubbing agaist the starter ring. I'm much more worried about the primary shaft then I am about the starter ring. Here a Picture to try to demonstrate whats happening  http://image69.webshots.com/169/4/12/59/2269412590 071760604RRkyvz_fs.jpg | ||
| Fx1200 |
There is supposed to be a thrust washer which goes between the bearing and the sprocket. When the thrust washer is installed and the sprocket is tightened there should be barely detectable play. I presume you are encountering the play with the sprocket off as the image shows. | ||
| Jos51700 |
The bluing on the starter ring gear is normal. It's from the manufacturing process. The endplay will be removed when the the primary sprocket bolt is tightened. The tapered bearings are loose on the crankshaft until loaded against the spacer by the front sprocket and sprocket bolt. FX1200 is correct, once tightened, the play (should) become minimal. The end-play spec should be in the service wear limits listings of chapter 3 of the appropriate service manual. .001-.005" with .005" being the SWL, in the S1 manual in the KV. | ||
| Alex |
We are talking XB, aren´t we? XBs do not have tapered bearings (Timken style). If You remove the front sprocket You can slide the crank all the way in until it bottoms out on the right side engine case. Yes, there is plenty of axial play with the sprocket removed. If You reinstall the sprocket there will be still noticeable axial play as the bearing itself has some axial play. That´s all pretty normal. And the blueing of the starter ring is normal as well (part of the heat treating process). Regards Alex M-TeK Engineering | ||
| Jos51700 |
Ooooops. I am wrong, Alex is correct! I apologise, and promise to keep antique tubeframe stuff in the appropriate board. | ||
| Lanretsr |
Thanks alex, makes me feel alot better. I thought for awhile there I was going to have to do my big bore kit sooner then planned. | ||
| Alex |
You´re welcome. |
