DavidC

   

Ken is right. Once the axle housing has begun to go oval the only answer is to machine them out and sleeve them. Replacing / overtightening the pinch bolt really only shows you how good the Amphicar handling can be. If there is any sideways movement then it needs fixing. The reason for not removing the rear bolt is that it is very difficult to get everything back together as well as the factory. The clamping area has to be super clean, the right tension has to be set with the dished washers and the bolt has to be the correct tightness.

What worries me about super high tensile bolts is that those sorts of bolts can be brittle so instead of stretching they just snap. I've seen a few cars where the rear wheel has come off, it causes a lot of damage to the tunnel area as the driveshaft is pulled out however normally it happens at low speed.

It is a bit of a weak point in design but remember the tyres Amphicar had originally. The tyres we use today cause much greater loads on the suspension which is also why the front wheel bearings can be an issue.

The problem is more related to miles and type of roads / driving style etc. I think if a car has done more than 20K miles it may well need some sort of attention. The annual safety test here means the cars never get so bad that you need opposite lock on corners !

Other areas of wear that can cause the same symptoms are the brass bushes and sometimes the axle itself is worn.

David C in the UK