3M offer a service where they will vacuum impregnate castings with their special sealant to seal porosity. I think they do a vacuum pull first to drag out any oil and stuff and after that use a vacuum to draw their pore sealant into the metal. I understand its a very common - 'out of warranty' fix for lamborghini motors!
Have you tackled the head yet?? Here is a trap for old players.... I thought the tappets were a tad noisy lately and today opened the inspection caps to find the exhaust rocker was loose - I was able to wobble it both up n down as well as in and out!! WTF!!
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I use a soft aluminium washer specifically for sealing banjos & oil plugs etc which has an advantage of when tightening down the rocker pipe screw it pulls up tight. The fibre washers provided today appear to be too soft and slowly squeeze out the way.Have you tackled the head yet?? Here is a trap for old players.... I thought the tappets were a tad noisy lately and today opened the inspection caps to find the exhaust rocker was loose - I was able to wobble it both up n down as well as in and out!! WTF!!
A month back (some 800 miles since) I had fitted a new ET100/1 modified rocker feed bolt replacing a worn component. I did not check at the time but have since discovered that the shaft portion of the new ET100/1 that passes through the hole in the rocker bearing ET26/1 was just a whisker longer than the hole in the bearing was deep. Result was with everything done up tight ET26/1, the rocker bearing was NOT being held/clamped securely against the roof of the rocker tunnel and was free to float about. No wonder it was noisy.
This did cause some minor fretting inside the tunnel but nothing requiring work to the head itself. The fix was to take out the 'nut' from the ET100/1 and carefully grind its length / shoulders to the point where it no longer protrudes beyond the outer surface of the rocker bearing. All back together now and the motor is a quiet as a mouse - well one eating nuts
Of course, having disturbed the oil return lines I now have a minor oil leak at the base of the rocker feed banjo - its the fibre washer ET189 - so next task , find a replacement for that! Anyone know what the ID of that fibre washer is meant to be??
M
Simply bearings have them at nearly £2 for two -5/16" id good luck with your search prices seem to have gone up a tad...
Yes .. but he left a day or so back to inspect his estates in Siam. Given there extent he will be gone for a month or more!
You have the wrong size. They are no where nere 5/16 id. They go over the hex head of the ET100/1 rocker feed bolt and I just measured one and across the tips of the hex they are 15.2mm. I use 16mm i/d x 20mm o/d aluminium washers 1.5mm thick and have just found a pack of 50 in the UK for £2.35. See:
