There was a strange tweeting/squealing noise emanating from the engine bay on the XKR which started a few months ago. It stopped once the engine got warm. I did mention it at the last service and they changed the Supercharger belt. The nest full of hungry birds returned shortly after the service. I tried using a tube and an old funnel to isolate the noise which I deemed to be the water pump. There was some notoriety with early water pumps so I changed it before Christmas. The noise did stop for a couple of journeys however it returned again! Not needing to use the car for a little while, it sat while I decided what to do next. A friend of mine from the JEC (Thanks Neil), lent me an electronic listening device which has a long tube that you place onto the various parts you suspect are making the noises and listen via a pair of headphones. You could not hear the tweeting but a rumbling noise and some were worse than others. One of the tensioners was noisier than the rest so that was the initial target.
I did a little research and there is a replacement tensioner and idler wheel set for the princely sum of £200. The set also included the Supercharger belt which I had just changed so I did not want to go down that route. I then came across a post on a Jaguar forum.
The solution is to replace the bearings in the various wheels and idlers and the post included details suitable part numbers. I ordered four bearing for a total of just over £14 so a big saving. I changed one idler wheel bearing without removing the Fan assembly but you do have to remove it so you can get to the bolts holding some of the other idler wheels on. This is reasonably straight forward.
Once you have struggled to get the two nuts off of the fan assembly, they are not tight or anything just there is no access to them. I used a small ratchet type ring spanner that also could be angled enough to get into the tight spot. (from a cheap set I brought myself last time I was in Aldi)
I removed the top plate holding the radiator in position and I found I needed to remove the top radiator hose and the air filter top to allow the Fan Assembly to be juggled out of the way. Once the Fans were out of the way you can undo the various wheels as needed.
I used a socket, a long threaded bolt & nut plus a large metal bar to pull out the bearings and tapped them back in using a suitably sized socket and hammer.
Made famous by Haynes, Reassembly is the reverse of removal, and once all back together, topped up the coolant that I lost disconnecting the pipe and went for a test drive. All seems well except for I started the engine with the plug into the air box unplugged so I have an engine MIL light illuminated. I’ll see if it goes off on its own after a few journeys otherwise I’ll plug in the ODB2 device I have and turn it off myself.
Back on the road and no tweeting …. for now anyway!
No good 🙁
A couple of days later, the noise was back see the video below:
Update – I fitted a belt (NCC7740AD) from Britishparts.co.uk. It was very tight, almost impossible to fit but once on there is no more tweeting. I have completed three journeys of about 150 miles in total and no repeat of the issue. Fingers crossed 🙂
The noise is back after nearly 5 years! The car hardly moved during Covid lock downs and after a short test drive it has just started tweeting again. I’ll try another new belt first this time and see how it goes.
It was just due to the alternator load as the battery decided it had had enough. A new battery and no longer any belt tweeting