Hey Guys

Took my S1 Cat out for a run yesterday.. Noticed she has developed a knocking sound in the rear end under hard exceleration. Sounds normal when cruising and theres no loss of power just a knocking sound if you plant the excelerator coming from around the drive tunnel under the back seat. I'm thinking could be the diff bush? Don't really know these cars mechanically all that well. Thanks in advance for any thoughts. Davo

 

My first guess would be the center driveshaft mount. There are small rubber bushes on it that need to be replaced every 20 years or so. You can make the shaft knock by pushing up and down on it from under the car.

 

Check out my albums - Drop Final Drive. It will give you a good idea of what the rear end looks like, and where to look for problems. I agree - go driveshaft first. I would also go to the final drive mounts to ensure they are still inact. That is a safety issue too - so ensure you get a good look before you put it up in the air. It could be as simple as a bad shock mount too, but not as likely as a driveshaft problem, a bad mount, maybe even a U-Joint in one of the shafts.

 

Thanks guys for your informed thoughts. Think I'm going to get my local Jag guy to take a look and get his opinion as I don't have the tools or skills to tackle this at home. I'll let you know how It goes. Checked out your album Ahabiam, you did an awesome job on the rebuild.

 

Got the knocking sound finally sorted yesterday. Indeed it was the centre driveshaft mount. The small rubber blocks had completely broken away from the mount. Luckily my mechanic could source a new mount. Pretty rare part as only the S1 & early S2 have this type of mount apparently. Cost me $105 - for a pretty inconsequential piece of bent metal with rubber blocks adhered to it. Mechanic said it was the 1st time he needed to changed a centre mount in a series 1 and reckoned the one in mine was probably the original part from the factory. So 42yrs old I guess.