Anyone got a helicoil kit?

Removed temperature switch from rad today, now have two lovely smooth surfaces to the threads. So, if anyone local has a helicoil kit that would kindly pop over, that would be most excellent.

After using the Helicoil tap are you gonna flush the rad out ?

Yes, I've flushed it today and will be doing again after the repair, obviously, but no joy with locating helicoil kit. I've decided as it it so well gone, that I'll probably go for something like Permatex® PermaPoxy™ 4 Minute Multi-Metal Epoxy and then tap a new thread in the rad, and die a new thread on the temp sensor, if the sensor fails to work after that, I'll just replace it.

I'll document it, if it isn't raining, and if it works, post some pics, if it fails abysmally, I probably wont.

Gotta be worth a Punt hasn`t it , I`ve seen this stuff used before to retain a threaded sensor .... as it is not a load bearing thread then I can`t see any problem with this apart from the fact that it may crumble a little if there is not enough for it to bond to . Mix it up and give it a whirl feller , got nothing to lose have ya .

It only blinking worked!

Not sue what it was before, but sensor and hole are now 12mm. All for the princely sum of £4.15 - cheaper than a new switch, let alone a new radiator.

Not posting pics tonight, as I'm cold, and tired. Might do tomorrow.

I'm pretty pleased though, as although I've tapped plenty of threads before, I've never used the dies in the set, and with nothing to guide it, it could have gone horribly wrong.

Just some info for those that may want to do this .

A Die is for putting a thread on a bar/bolt , Taps are for putting a thread in a hole for future reference in case that causes confusion in posts

You can get 3 types of Tap , you have the "Lead In" one that has a longer taper on it for starting threads , a "Secondary Tap" which helps cut a thread into the hole with less of a taper on the beginning and then a "Finishing" Tap which has hardly any taper on the start and has the correct Vee profile for the pitch of the thread . Now due to the depth of the Radiator the first option would probably not cut enough thread before it bottoms out in the hole so the Secondary Tap would be best to start off with . Once you have filled the hole with the compound and it has set , you are best to drill it out to the correct size for the Tap , you can buy a Zeus book from places like Smiths for a few quid and they have info for drilling out holes for the Tap required . Cutting a thread is best done with some lube like a light oil and a Half turn is enough to cut into the material , back it off the same amount and a touch more to break off the material into the flutes on the Tap , this stops you cramming the swarf into your new thread and knackering it . Keeping the Tap straight as possible and parallel with the hole you have drilled is tantamount to getting a good thread . You can use the Finishing Tap if you like but it is not generally needed .

Good work there Boot and look forward to seeing the pics

Some fill the flutes of the tap with grease to help capture the swarf and keep it from migrating into places you don't want it.....like the inside of the radiator.

Good tip there Pete

Yes, quite. I didn't do that, but did make sure the rad was rinsed/flushed with the sensor side down, and cleaned out slowly and thoroughly.

All seems to be ok today.

Will post pics later.

OK, so, this might not be the prettiest repair, rather than throw money away, I decided to go to my local engineers merchants and bought some RectorSeal Epoxy Putty for £4.15.

I'll add here, if I were to repeat this process, I'd try to allow more time, to let the product cure a bit longer, and to file down the surface a little neater.

Now, we ain't aiming for perfection here folks, nor are we aiming for fineart photography, we're aiming at getting to work in the morning.

The stripped sensor.


The stripped recess for the sensor.


The filled recess - the first attempt, putting the putty around the inside of the recess, didn't work well, it wouldn't stick, I dried the hole off with a hairdryer and went at it again, this time allowing the putty to form an lip over the top, which was filed flat after hardening.


Filed flat with a new thread tapped.


Temp sensor with a new thread, the end was filed down to make a smoother less jaggy tip than in this picture before re-fitting, the o-ring was removed while putting the new thread on.