| Re: Vibration.... |
Subject: Re: Vibration.... by bogus on 2012/7/23 2:04:54 I think I found it... I just did the first op test... with both wheels off, and the left halfshaft out, I ran it up to 76mph (the manual does not recommend doing this for long) and there was ZERO vibration. NOTHING. Oh, I did bolt the brake rotor in place, having it flop about was a bad idea. So that explains that... A few lessons learned: 1. dimensional tolerances are seriously important. 2. See #1. If the ujoints are too tight and are not able to move under their own weight, they will fail to move properly and set up vibrations as they resist said movement. The main drive shaft is seriously prone to this, because the offset is only a nominal 1*, just enough to keep it from being straight, setting up a different vibration!!! I suspect that the reason why most people are unaware of these problems/issues that that a) there are not a lot of C4's with 180k+ miles and b) most folks still take their cars in for service, vs DIY - especially for something like ujoints. My guess? The garage gets them and then finds the yokes marginally compressed, calls the owner and sells them a new set of shafts. Problem solved. I also suspect that over time, and ujoint changes, that the yokes get marginally compressed due to mistakes made with the press or vice. The other problem is debris inside the slots where the e-rings go. If they are packed, or worse yet, filled with aluminum shards, they will effect fitment, won't allow the ujoint to center properly or over tighten the fitment so it won't rotate properly. In short, there is a lot going on down there! I will not be 100% sure this is fixed until I get it out on the freeway... I guess that will be tomorrow morning at this rate. Off to finish assembly. |
