Tarka is sorted, hideous squeal eliminated. I'll collect the car on Friday.
The source?
Nothing that we considered or discussed.
One of the auxiliary devices driven from the front of the BMW N62 engine is a vacuum pump. This provides vacuum for the brake servo and on a BMW car, other functions: there are 2 vacuum ports in the pump. .
On a Morgan Aero the second vacuum port is caped off.
The cap split: what we could hear is air being sucked through the cap.
Replacement? Less than £5.00
Labour? 5 .5 hours.... Bonnet, Cowl and 1 wing off. The pump is low down on the off side.
Williams discussed this issue with Morgan Motor Company. It is a "known but rare issue" !!
So, now all with the 4.8L BMW motor know.
If you car starts making a noise like a squealing fan belt, which starts intermittently but becomes continuous, it is very probably this problem. Of course, it isn't a BMW issue, but a Morgan one.
