I'm doing the top mounts on a 1997 Mk3 Golf 1.6 GLI (101HP) at the moment. The car is equipped with Koni sport suspension and is using Mk2 spring caps. I'm replacing the Mk3 top mounts with Mk2 items as these sit slightly lower and are more snug against the spring caps.
My problem is that, the threads have been very slightly worn by where the spring cap was sitting against the damper spindle which makes the nut tighten up before it's in contact with the top mount bearing.
My question is specific to this problem, as the nut is M14 x 1.5 and therefore beyond the scope of most tap and die sets. Before I go ahead and order a specific die, I was wondering if I attacked it with a thread file if that would help.
Doing some research into various thread pitches I was surprised to discover that all metric threads appear to have an internal angle within the groves of the thread of 60 degrees. Therefore I wondered if it would be possible to devise a tool that simply cut a 60 degree grove to the required depth, if that would be a more effective universal thread repair tool? Perhaps use threads further up the bar as a datum point to keep the tool cutting blade in the correct place?