Injector clamp stud loose. A problem found and solved

[isisalar]

Some of you will recall the unfortunate problems I've encountered whilst curing the leaks and whistling from my injectors. As a further attempt to cure the whistling I got some new nuts as per the BOL but before they arrived I was told by an injector specialist that this was rubbish, old ones are fine.
I resolved to check the tightness of the nuts before going any further and to my horror no.4 didn't feel right, further investigation revealed the 8mm steel stud set in the alloy head was rotating and bits of helicoil were coming out. The helicoil had obviously failed, and not for the first time as this was the one that I thought I hadn't tightened properly and had popped out on the first test run. What to do? After thinking about it, getting some confirmation that it wasn't a stupid idea from my favourite indy, and doing some research, this is what I did. I hope it might prove helpful to someone in a similar situation.

Removed all the bits in the way. Drilled out the hole for the stud to 8.5mm this size is critical. very carefully tapped a 10mm metric thread into the hole, inserted new 10mm stud, drilled out the clamp and the washer to 10mm+ and re assembled. It took a lot longer to do the job than to write about it but it has solved that problem.

Sadly the whistling remains and I'm not entirely sure it is the injectors, but that will be a different thread.
Kind regards
Paul

[CitroJim]

Excellent work Paul and nicely saved the aggravation of fitting a replacement head...