Whilst waiting for the P38 on the tank base to go off I thought I would tackle a job I have been putting off, namely the oil cooler mount to the rocker cover. When I took the oil cooler off to refurbish it one of the rubber mounts parted company from the washer and stud that screws into the rocker cover casting. I was going to renew them anyway but when I tried to remove the threaded portion from the casting the threaded part sheared in the casting about 4mm below the face of the casting. the end of the sheared thread was of course not smooth but extremely jagged and therefore not good for starting a drill into. The shape and dimensions of the casting meant it was impossible to mount the casting into a machine vice so that a pillar drill could be used, - it had to be held in the bench vice and a hand held 18v battery drill used
For the last two months every time I saw it I sprayed it with penetrating oil in the hope it would come out easily. I had 2 options drill a 3mm hole in the sheared stud to put an ease-it-out in and hopefully save the thread in the casting or drill it 6mm then 7 mm and re-tap the hole 8mm, but I was not certain I could get a male /female vibration damper with an 8mm male thread. The ease-it-out option was chosen and a 3mm ease-it out tried but it would not budge and I was frightened of breaking the ease-it-out in the sheared stud. I then tried a 4mm hole and larger ease-it-out was threaded in. the results are in the pictures below.
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