| Author | Message | ||
| Gareth Kerry (224420)
New member Username: 224420 Post Number: 6 Registered: 6-2002 |
No there wasnt an excess of movement in the actual diff although this is what I first suspected when I wobbled the drive flanges. And yes there is a notch punched in the original washer, this has been replicated by the roll pin (in fact its a scroll pin which is slightly different) on the new washer.Although I machined a recess of 1mm the actual protrusion was nowhere near that much but I thought it prudent to go slightly deeper. | ||
| David Feinberg (Fastradio2)
Junior Member Username: Fastradio2 Post Number: 171 Registered: 4-2002 |
Gareth, Although the solution you have derived appears to solve your current problem, the underlying problem still exists...which I believe to be a diff preload issue. If there is considerable side to side movement in the axle flanges (at the diff housing), the dif carrier bearings would be high on my list to inspect and likely replace. It is important to note that the pre-load can be "in specs", yet not have the diff carrier centered in the housing. The situation would cause reduced clearance between one of the axle flanges and the case. Having recently spent considerable time seting up a BB differental, although different in design, the concept is the same. The are two goals that need to be acheived simultaneously. One, the preload...the other, the corresponding ring/pinon engagement pattern. If your diff preload measure correctly, et your in the situation where the diff axle flange protrudes too far into the CV axle flange, the diff is not centered properly in the housing. There are selective shims that can be move from one side of the diff housing to the other to "center" the diff in the carrier housing. When all is said and done correctly, the stub axles from the diff should be ever so slightly recessed in the CV axle flanges. Regards, David | ||
| '75 308 GT4 (Peter)
Intermediate Member Username: Peter Post Number: 2078 Registered: 12-2000 |
Ooops!  I forgot that it does use a lock-washer behind the bolt... | ||
| '75 308 GT4 (Peter)
Intermediate Member Username: Peter Post Number: 2077 Registered: 12-2000 |
Gareth, did the original washer have a "tooth" punched down on the edge? This is supposed to lock down the fastener (although its incorrect, the locking system should be behind the BOLT...). I suppose in a way, the digging action of the "tooth" would take some slop out. I didn't notice any protrusion of the diff. drive spline with the drive flange on my car... Hans, the registry is in the works, but I haven't had the time to get it on the web... | ||
| Gareth Kerry (224420)
New member Username: 224420 Post Number: 5 Registered: 6-2002 |
Here are a couple of quick sketches,please excuse the lack of detail,they are from memory   | ||
| Hans E. Hansen (4re_gt4)
Member Username: 4re_gt4 Post Number: 267 Registered: 4-2002 |
Another 'GT4 guy?? People are starting to make noise about a registry. | ||
| Mitchell Le (Yelcab1)
Member Username: Yelcab1 Post Number: 431 Registered: 11-2001 |
Post some pictures, Gareth | ||
| Gareth Kerry (224420)
New member Username: 224420 Post Number: 4 Registered: 6-2002 |
I thought Id better let everyone know about a potential problem I have encountered on my 308 GT4.Whilst pulling away recently I had a nasty scare as I had no drive and was stranded in the road....thankfully nothing was coming down the road! On getting my car back home I found that the nearside driveshaft had popped out of its spline. When I removed the shaft I could see that the sprung clip had fallen off and this gives enough movement for the spline to fall out completely. This seems to be the result of two problems,firstly the groove in the shaft is not deep enough which makes it easy for the clip to ride over the edge and secondly the drive flange on the diff that the driveshaft bolts to was slightly loose.At first I thought the fixing bolt must be loose but found it to be tight so I removed the flange and studied it closely and it would seem that over the years the back edge has burred slightly where it has been tightened and moved back against the mating face by only a few thou,this is enough to stop the fixing bolt and washer clamping as it just tightens on the shaft thus giving the slight movement on the flange.This is what I think caused the slight vibration and was in effect "Hammering" the sprung clip and caused it to come off. To cure this I had an engineer machine a recessed washer to replace the original clamping washer so it actually clamps around the outside of the shaft and makes the flange tight again.I also had a roll pin inserted into the washer to replace the peined section on the original which locates into a hole on the drive flange to stop the washer rotating and loosening the fixing bolt I have also had deeper grooves machined into the shaft and "proper" circlips fitted,this seems to have cured the problem on that side and I am now having the same mods done on the other side just in case. |