Cylinder Head Thread Stripped

[mrfirepro 127 1 Cars]

Got around to fitting the head today only to find that one of the threads has been stripped. As part of the rebuild I had run a tap down the threads and didn't notice anything different from the other threads.

 

Got to about 120 degrees of stage three tightening and then it let loose.

 

What are my options..

 

1. use a thread repair kit Helicoil I think there called?

2. get a bigger head bolt say M12 and drill & retap the thread

3. get another block (already on my third)

[Harni 6]

Helicoil if i was you. Most engine shops/engineering shops will do it properly for you for a couple of quid unless your handy with a drill and tap your self.

[Tom Fenton 1,524]

Helicoil it, I've got the kit and have done a few with 100% success. No doubt the naysayers will be along shortly to say how crap helicoils are, but the simple fact is that a helicoiled thread into alloy is stronger than the original, FACT.

[mrfirepro 127 1 Cars]

Brilliant Tom/Niall, I cant tell you how happy that makes me.

 

Was thinking of this kit

 

http://www.ebay.co.uk/itm/M11-x-1-5-V-Coil-Fits-Helicoil-Wire-Thread-Insert-Repair-Kit-/111207003823?pt=UK_Hand_Tools_Equipment&hash=item19e47436af

 

 

On another point this was only the third bolt that was torqued up, will I need to replace the head gasket now

Edited February 9, 2014 by mrfirepro

[Miles 331 1 Cars]

Had loads of helicoil's strip (From different people too), No idea why so I always use Timeserts and never had any issues at all, and again stronger than the originals

[Tom Fenton 1,524]

You want the kit with double length inserts.

[mrfirepro 127 1 Cars]

Tom,

 

are they the ones know as 3D? (I take it that's 3 times diameter??)

[Tom Fenton 1,524]

Depends on the supplier, could be 3x depth or 3x dia. Best to measure depth you need then make a phone call and order the most suitable kit.

[Ramigojag 19 1 Cars]

This happened to me but it turned out the headbolt I was using that we're supplied by a motor factor were fractionally too short. So just double check

[mrfirepro 127 1 Cars]

Hi Callum,

 

Thanks for that, checked the bolts and tried another one in the same bolt hole, same result.

[petert 549]

I've never had any problems with the long helicoils.

[large 33]

I use helicoils in work all the time, now and again they do go. But the bolts are in and out a couple of times a month and are torqued down to 1300 N/M.

So for your application as said would be fine.

[Telf 222 2 Cars]

hi all-ive got his issue with a 1.6 block- an engineering place says they will fix it in situ for £50-does this sound about the right price for a repair?

 

thanks

[mrfirepro 127 1 Cars]

Telf,

 

The repair was really easy took about 5 mins and all in the kit was £38 including the long inserts.

 

I dont know if you ever get around this way, but if you do I'm happy to do it for you.

 

Got the kit and 3D inserts from South Essex Fasteners, Speak to Tony on 01702 615326

Edited March 2, 2014 by mrfirepro