Meh, just finished installing of my new radiator in my FC, cut the samcos to the right length, and all that stuff.
Removed coils, overflow bottle, intake battery airpump and everything in my way. Gave it a good cleanup before putting everything together.

Well now my problem is that I probably screwed the lower coolant sensor thread on the radiator.
Had to trim the mounting holes a bit, but thats not a problem. Brand of rad is not of any concern as it would be a genereal issue with all aluminium rads.
Now laying under the car and mounting back that sensor and tighten it. Did not apply a lot of force, first turns with hand and then carefully with 27 er wrench a bit and then zapp... it turns turns turns and wont stop.

Is there a possibility to save the radiator/thread any tricks ? I am super pissed right now, all that trouble to get that stuff (and other things) here to LUX, paying shietloads of money (customs included 15%) and then it snapped after everything is installed and ready to go ...

I want the car running til friday, have a spare car now but this issue is pissing me big times.

Any help is greatly appreciated.
Steven

 

do you mean the threaded end snapped off or you just killed the thread? any capable alloy welder would be able to weld it on again or replace it. If the thread is a bit munted use a thread file or die or if it is horrendously ruined then replace it, again the alloy welder route.

 

Thanks for your reply.

No its just the thread thats ruined, only the last 2 or 3 turns are functional.

Steven

 

you got a pic of how bad it is so i can come up with a typical kiwi diy fix

 

Unfortunatly I dont have a pic right now, I checked the thread with a boroscope but it looked fine.

With minimal effort you could also push the sensor in with your fingers, without turning it. So the threads must be damaged in some way.

I will call a engine shop tomorrow, they repair and do all kind of work on engines and metal stuff, they might be able to fix this.

Sadly I have to remove the rad and bring it to them, getting again lots of blessures removing stuff in the bay.

Steven

 

Honestly, very little stress is on that sensor. And that lower sensor is such a minor thing it is simply eliminated with high performance radiators such as a koyo and the two wires simply connected.

That said, you could probably get away with some red thread lock as is.

 

What is the purpose of that sensor ? Measuring temp ?

Thanks

Edit:

FSM describes it as a Water thermo switch.
Conductivity under 90 Degree Celsius. Everything over 90°C = no conectivity

 

Helicoil it.
It's a little metal spiral that you install to replace the threads. Pickup the kit, drill the hole smooth, tap for the Helicoil size and wind the Helicoil in.

http://www.google.com/search?client=...=1237&bih=1009

And probably rinse out the radiator to keep the little metal bits out..

 

Permatex makes a thread repair liquid as well... believe its a JB weld type of product. I actually used it on the bolts around the thermostat. It cracked the aluminum when it expanded... be careful!

 

+1 ive worked 10 years as a mechanic. if you cant re-tap the threds put a helicoil in it.

This way you can still remove the sensor down the road too.

 

I'm frazzled why you put the sender on under the car.You could have done it while the rad was off the car,cleanly..but Hell,that is ok.
If you use a gob of JB-Weld that would do,or Helicoil would suffice too...You can also ponder eliminating that sensor too.(I got a s5 Koyo Nflow and took that sensor off my s4 harness,no qualms about it).Plug the hole with one of those expandable rubber plugs.

 

JBWELD that sucker on there.

 

This happened to me. The plastic threads on the sensor don't hold well to the aluminum threads on the radiator. I ended up fudging it all up and getting the sucker welded shut and running without a sensor.

Even if you managed to fix the threads, it probably will never fully seal.

This is what I would do if I could do it again. That or try some Teflon/Plumbers tape. I did it with the coolant overflow nipple (mine was a screw in and the threads were damaged) and it never leaked again.

 

Hello,

thanks for all the answers, today I spoke with the engine shop and they said it would be best to put a helicoil in there.

I think thats the best solution for now, not too expensive and sensor can be reused, inserted/removed when needed.
Teflon tape might be a good idea too, just for the peace of mind.

As for the sensor mounting after radiator installation. I did not pay too much attention to this as I first removed the sensor and wanted to do it in reverse (sensor last) when mounting back.
But you are right, I should have installed it first ...

Getting the helicoil installed tomorrow after lunch.

thanks
Steven

 

Hello,

small update: helicoil is installed, radiator flushed, sensor back in place with copper washer and teflon tape. Sensor goes in super smooth and does not leak.
Rad mounted and everything cleaned and back together.

Car was ready for the dyno run on friday, cooling system performs very well, temperature is slightly below OP temperature on the old rad and does not rise even
at WOT and full load.

Great.

Thanks to all for their ideas.
Steven

 

Nice work. Thread in aluminum should always have steel coil inserts installed.