gman35

I attempted removal of the drivers side water temp sensor. I had been soaking pb blaster on it for three days.Then sensor broke off leaving the threads in the hole. Has anyone else had this problem?? I figure my only two options are a broke nipple extractor or a tap to carefully thread the brass out of the hole. The heads are aluminum which I figure is softer than the brass water temp sensor. the broken threaded part that is in the head appears to be thin so I don't believe the extractor will work.
Any ideas,opinions or help will be greatly appreciated.. I knew this header install would be tough.. that is why I stalled so long to do it,, thanks, gary

1984Z51auto

I believe that I would pull the head and take it to a pro to get the threads cleared out. While an extractor might work, its a big risk with an expensive head. I assume the car is still drivable now... might be able to take it to a specialist??

gman35

I worked some on it last night luckily it is in a very accessable spot.. I ordered a set of broke nipple extractors last night also. I also came up with a few more ideas and spoke to one friend that had the same problem more than once. I will pass the outcome when it is through. thanks, gary

gerardvg

Hi

The temp sender will need to be drilled out, use a slightly smaller drill bit than the threads.

I would grind it flat and use a center punch to drill the center, start with a small drill bit working up to the thread or large easy out.

Using a larger easyout will be the best bet as you do not want to damage the threads or break the easyout, if you do not feel confident bring it to a mechanic with experience of doing this.

It is fairly easy, give it a go.

Easy outs are hardened so take it easy, hammer it in the hole you have drilled and that should loosen it. You can drill through easy outs but its hard work, so take it easy do not overdo it.

VikingTrad3r

what Gerard said. GO SLOW.

you don't want to get sloppy then have to put in a permathread/coil.

VetosVet

If you are buying easy outs also get a set of reverse twist drill bits. They sometimes reverse the broken portion out of the hole.

gman35

Thanks for all the help guy's my C4 is a 1987 with a L98 in it.When the fan switch snapped it broke with maybe two threads left outside the head. I had been soaking it with pb blaster for three days. I ordered a set of broken pipe nipple extractors online after much research on them.I believe I will be able to remove what is left in the head with the extractors.
I have been taping the area with a rubber mallet and blasting it with pb blaster since it broke,, thanks again for the help Gary

8a8mfh

I'd leave it alone and relocate the sensor.

gman35

Thanks for the reply.. but I can't leave it alone because now there is a hole sitting there open and no way to plug it.. I am hoping the broken nipple extractor does the trick..thanks, gary

gman35

I attempted removal of broken fan switch today. using broken nipple extractor I was able to back it out about a quarter thread before brass gave way and extractor spun out. My next attempt will be to tap out the remainder. It is not very thick at all and the brass is soft. Does anyone know what size the threads are on the 3/8 fan switch? I was going to take the broken piece with me tomorrow and try to get the correct tap.
It appears to be 3/8 and the replacement oem switch is 2 piece. The part that goes in the head looks like 1/2 and then the 3/8 switch threads into it. If I can not get the broken one out... I will drill it out and tap it to the larger base piece and then put the 3/8 into it. any advice or knowledge is appreciated. thanks, gary

8a8mfh

If it's as thin as you say you should be able to collapse it and pry it out, and keep the original thread size.

gman35

Roger that, I started cutting slots in the 12,3,6,9 o'clock positions earlier today. Thinking I could take a small screw driver and and collapse it in and then remove it.Really don't want to have to drill it to the adapter size of the jet switch that I have.
Even though it would be better to put a wrench on the adapter and a wrench on the switch to screw it out in the future.

HlhnEast

As always, if you need help and I am not working, I will be glad to help if you need it. Hope you get it solved.

Good luck!

gman35

Roger that my man,, I have been working on it a hour here and a hour there.. being retired there is no big rush. The fan switch got broke during the disassembly. I bought taps today and am suprised that it was 3/8-18 thread npt and the adapter was 1/2-14 thread npt. I thought the whole car was metric?? sure seems weird, I could use a hand on the drivers header my first attempt alone had to be aborted with just one set of hands. my cell is 904-228-1196 so call me when you can. I still have new full roller rockers, valve covers, DUI distributor, and air pump delete to do. And I just aquired a 421 ci short block.. ai yi yi will it ever end. thanks Gary

Cliff Harris

The CAR is metric, the ENGINE is not. Still a classic Chevy small block.

gman35

First of all thanks to all who replied or viewed this thread. Today was pay dirt.. I took a mini angle grinder with a burr bit and a small stone grinding bit and slowly removed broken brass fan switch from the drivers side head.
I then took a 3/8x18 npt tap and slowly tapped the remaining brass out. After I cleaned it up I installed the new jet performance fan switch. I then redid all the electrical grounds on the car and added some extras. I then wired up the new 3 wire heated o2 sensor. I will be finished soon, cats are gone.. plus new Y pipe with crossover and new turbo mufflers.. yay the awfull stock exhaust is gone,, thanks again to all, gary