Bottom bolt on clutch slave unit cannot be tightened

[MtheTiger]

Yesterday I refitted my overhauled clutch slave unit. Of the three bolts the bottom one cannot be tightened anymore. Iguess the female thread in the aluminium casing has gone bad. :x    :x    :x    :x  

Any ideas how to fix this myself?
I'm thinking of these options:
1. longer bolt and hope that there still some flesh there
2. cutting thread in a different pitch
3. cutting thread for a larger bolt (don't know if there's any room for this though)
4. perhaps helicoil or liquid metal
5. another better solution?

[JetdocX]

Helicoil is your best bet, but  slightly longer bolt might be your savior.

[nightrunner]

I would go with Helicoil or one of their competitors.  If there are some extra threads at the bottom, it likely won't be too many so I would not trust the strength.  

Another possible option is to cement a stud in the hole.  I have not seen the slave cyl so maybe a stud just wont work for clearance reasons.  But in general its another option for stripped blind holes.

[MtheTiger]

Will do that...thx!

[Mustang]

I have found these to be far superior to heli coils , especially in applications where the bolts are removed for dis assembly and reassembly



I get them from mcmaster carr here in the USA , there must be somewhere where you are that sells them

http://www.mcmaster.com/#threaded-inserts/=9cdfli

[MtheTiger]

yeah seen them inserts too on the interweb & in forums. They say that these inserts need more flesh around the existing hole to work because they are bigger/wider than the helicoil family. Don't know if I got the space for this though.....

[MtheTiger]

For an insert for the M6 bolt that is used here the diameter of the hole that has to be drilled is 9,3mm!