Thread repair help!!

[clivvy]

hi guys,

I urgently need help/advise!! I need to re-thread the thermostat housing on my 03 TDi, the bolt facing the radiator has stripped the thread in the housing.

I measure the bolt at about 7mm, can anyone confirm? Also, would that mean I need a 7mm thread repair kit?!?

please help as I need to order the kit so I can do the work at the weekend....

alternatively, if anyone has a housing for sale cheap ill take that to save a bit of faff...!

 

[rustic]

hi guys,

I urgently need help/advise!! I need to re-thread the thermostat housing on my 03 TDi, the bolt facing the radiator has stripped the thread in the housing.

I measure the bolt at about 7mm, can anyone confirm? Also, would that mean I need a 7mm thread repair kit?!?

please help as I need to order the kit so I can do the work at the weekend....

alternatively, if anyone has a housing for sale cheap ill take that to save a bit of faff...!

If the bolt is 7mm you will need a 7mm helicoil set.
There are alternative to helicoil, cheaper but do the same thing.
The kit normally has the correct size drill, special tap, helicoils to insert and a break off tool that snaps of the little tag, prior to inserting the bolt.

An alternative is...
Tap the hole to 8mm, slightly enlarge the hole in the stat housing, and use the correct length bolt. Make sure the bolt head can rotate, otherwise you might need a spacer between the bolt head and the housing.

7 mm is not a regular size.
Make sure you have the correct pitch...

For normal metric bolts,
6mm bolt has a 10mm AF head,
8mm bolt has a 13 mm AF head

Not sure what a 7 mm has, but looks like it could be 12 mm from what you have said.

Hope it helps,
best regards,

Rustic

 

[stinka]

Fill it full of plastic padding liquid metal, then drill and tap, or as said drill it to 8mm and tap

 

[clivvy]

cheers chaps,

ill try find a 7mm helicoil kit/thread repair kit, the one I have is too big!

 

[clivvy]

ok im struggling to find the right kit, so im worried im measuring the bolt wrong. I can see lots of 6.7mm kits, 8mm, but not so many 7mm.

Can anyone possibly help, and measure the bolt for me using a micrometer or something more accurate?

I really cant afford to buy the wrong kit!!:bow

 

[cncfabs]

ok im struggling to find the right kit, so im worried im measuring the bolt wrong. I can see lots of 6.7mm kits, 8mm, but not so many 7mm.

Can anyone possibly help, and measure the bolt for me using a micrometer or something more accurate?

I really cant afford to buy the wrong kit!!:bow

Thats cause m7 isnt common size it will be 8mm.Japs dont use 13mm hex heads will be 12mm

 

[clivvy]

Thats cause m7 isnt common size it will be 8mm.Japs dont use 13mm hex heads will be 12mm

ok, yes the head of the bolt is 12mm (takes a 12mm socket) but maybe im measuring the bolt wrong? Im just struggling to work out the correct size thread repair kit so I can use the same bolt. Any ideas?

Do you have any thermostat housings for sale (I means the part where the thermostat goes in, not the cover that the rubber pipe is attached to that sits over the thermostat) and if so, how much? If cheaper than a kit id rather do that because it would be an easier job I think?

 

[cncfabs]

ok, yes the head of the bolt is 12mm (takes a 12mm socket) but maybe im measuring the bolt wrong? Im just struggling to work out the correct size thread repair kit so I can use the same bolt. Any ideas?

Do you have any thermostat housings for sale (I means the part where the thermostat goes in, not the cover that the rubber pipe is attached to that sits over the thermostat) and if so, how much? If cheaper than a kit id rather do that because it would be an easier job I think?

Yes have one the thread is m8.Are you aware that only 2 of those holes are tapped the other should be a long bolt thats tapped into the block.

 

[clivvy]

Yes have one the thread is m8.Are you aware that only 2 of those holes are tapped the other should be a long bolt thats tapped into the block.

cheers CNC that helps a heck of a lot, M8 is common and plenty of kits for less than £10. Yes I am aware of the extra long bolt, thankfully that one seems fine as does the other smaller bolt.

thanks again for your advice