For while there has been a rhythmic squeak from my XJ40 when first driving off. At first I suspected the wheel bearings but when revving the car slightly at rest it was still there, so now I suspected the fan belt needed adjustment. This morning at first the squeak was not there but I noticed the battery was not charging either (broken belt?). But eventually the charge started and so did the squeak. So I now suspect a bearing on the alternator. Anyone had the same? Greasable? Repairable? Sources of spares: bearings or alternators in Australia?
I have an alternator from my old ‘88 somewhere in the garage if worst come to worst.
Thank you very much Robin! I should have realised. A squeak for the first km or so meant that the alternator was only squeaking when it was charging heavily, rather than when it was cold. So that suggested that the belt was slipping so should be tightened, which is easy and what I have done, with apparent success so far! Robin’s offer is great and if I had to buy new then the only source I have in Aust is $230 Aust dollars!
Also check to make sure your fan clutch is not locked up solid. That once happened on my 1990 XJ6 and it caused the belt to slip when rev-ing the engine up from idle or at engine speeds greater than about 3500 RPM. Apparently a fully locked up clutch puts too much strain on the belt even if the tension is correct.
Another source of squealing at startup or upon engine load is a failing crankshaft damper.
Alan …
Purchase a mechanic’s stethoscope (less than $10 at Harbor Freight) and place the long metal probe on your alternator while its running. Trust me there will be no doubt if the bearings are grumbling !
OK … Want to be a cheapskate, then take an empty soup can and tape a straightened metal coat hanger to the side. Now listen to the open end of the can while you touch the coat hanger to your alternator. Not nearly as elegant as the stethoscope but it works.
… AND you just fixed lunch.
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Thanks chaps! (traditional English for ‘guys’!). All good sound tips, and lovely illustrations. However, it does seem as though this time it was the much simpler case of a loose belt. The squeak was only at first when the alternator was under load recharging the battery after starting. The squeak has entirely disappeared since I adjusted the belt tightness (easy: there is a rod at the top with two 15mm nuts that can be got at with an open ender and I shifted those about 2-3mm. I plan to back that off slightly and then on again as necessary so that the squeak just disappears and I am not putting those bearings or the belt under too much load.