mangocrazy wrote: ↑Tue Sep 12, 2023 3:50 pm It was all going so well, right up until the time it went to shit...
Before fitting the head and as part of the block prep and cleaning I ran an M10 x 1.25 tap down the threads in the block to clean out any crud and make them ready to accept the head bolts. Nine of the threads cleaned up very nicely, but one gave serious cause for concern - the one between cyls 3 and 4 on the inlet side. When I ran the tap down it there was consistent resistance to the tap, nearly all the way down. This reminded me that when undoing the head bolts back in May one bolt had been particularly difficult to remove and had needed me to use quite serious force to unwind it. After tapping it I tried a head bolt in the thread and discovered a worrying amount of slop. It only started to straighten up and fly right towards the end of the thread.
We decided to carry on and torque the head up in stages (as per instructions) and all bolts passed muster at 20 lb/ft. When we upped the torque to 40 lb/ft Nigel (who was wielding the torque wrench) came to the iffy bolt, tightened it up until nearly at torque, at which point it just went floppier than a floppy thing. Many imprecations and bad language followed, as you can imagine. We didn't even get to the point of torquing the bolts up fully (60 lb/ft).
So now we need to try and track down a supplier of an M10 x 1.25 helicoil kit in a part of France where engineering suppliers are few and far between. I've enlisted the services of a Brit ex-pat I know who runs a number of old cars and he wiil try and track down a source for a Helicoil kit, but as of Tuesday afternoon I've heard nothing back. As a back stop I've ordered the kit I need off eBay, but it probably won't arrive until next week.
So not the best of news to report. Both of us want to get this thing buttoned up and finished before Nigel flies home on Thursday, but that is looking increasingly unlikely with each passing minute. It also means I will need to find another helper, as lowering the head down in a controlled manner is much easier and safer as a two man job.
No-one ever said it would be easy...
I hate it when that happens. For me it's always the frigging 'last' bolt/nut that I'm torqueing up: just as I'm beginning to get that self-satisfied feeling of a job well done!