I installed my thermocouple the other day using the hoot method, and I am not sure what exactly I did to screw up the insert but I did. I drilled, and started to tap, in and out until it got a little tight so I stopped. When I went to install the insert some of the threads got screwed up, so I took it out and cleaned them up as best I could. I then retapped to clean out the manifold. I put the insert back in and got it in further, but now I can not remove it at all without possible damage. I guess it jammed in there pretty good. Do you think there can be any possible problems come out of all of this, or since it is in there should I just leave it alone and not worry about it. I thought about getting a new insert but like I said, I'm not sure I could get it out without damage. I guess I worry about things too much, but what do ya'll think?:o:

BTW it was a banks thermocouple with the 1/4 npt insert.

Sounds like it cross threaded, as long as its tight just leave in there.

I would agree with Noreaster, if there is no leaks and no other issues leave it alone for now. I think it will be ok. Might want to check it every now and then to make sure it is not leaking. Good luck...

Yeah I'm pi$$ed that it happened, cause I was extra carefull. But I think I didn't tap in far enough, It is definetly tight.

Kinda planned on leaving it because I figure if I try to take it out I might FUBAR the whole deal.

Yea just leave it. Even if it leaked slightly it doesn't matter.

The problem is tapered (pipe tap) threads allow you to cross thread very easily, even with the tap if you aren't careful.

Did you use any thread tape or pipe dope? If not it may have just siezed/welded itself to the manifold.

No thread tape or pipe dope. Some of the threads were messed up so I'm thinking cross threaded and was worrying about grindings from that.

Brass is softer than the cast. If you screwed it in a couple threads you are OK. If I remember correctly the manifold is only two or three threads thick anyway. What size bushing did you use? If you used 1/8 you can always go out to 1/4 if you have a problem. Later! Frank

Drill it out and start over again, otherwise it'll screw something else up.

good luck

I Don't think the insert is brass, and it is already 1/4" npt so I don't think I can go bigger.

If you really want to remove the fitting. go to an electronics wholesaler. get an aerosol spray can of co2 or nitrogen. Start the truck let it run untill the manifold is hot but not burning hot, use the fine spray jet of co2 directly on the fitting and turn it out.

good luck.

dont forget to use anti sieze on all dissimilar metals.

Well I was cleaning the shop today, and I went to put the tap that I had bought specifically for this project. It had chunks out of the tap,-:t that looks like it is the root of my problem. This wasn't a cheap tap(in my mind anyway) it was $21.00. I bought it from a specialty Nut & bolt place, I have always got good quality stuff there, but it looks like I got a low quality tap. Maybe I am wrong but what does a good tap cost?

I have to agree with the previous gentleman that stated "leave it alone if it doesn't leak". When I installed mine I ran into a similar problem by not running the tap in far enough. Couldn't get the probe to start into the threads so after a few minutes of trying it dawned on me what the prob was. I ran the tap in further and it was fine. If your pyro fails at some point you can always tap a 3/8"npt hole and bush it down to the pyro thread size....Cal

McMaster-Carr catalog lists 1/4 pipe tap at $14 I never had a problem as you described with a tap except over torqueing and breaking off small one. You are lucky you didn't do that!

I had the same problem with mine, wasn't cheap, I guess just bad metal. Mine busted off in the manifold when I started to back it out the last time. Good thing I had some needle nose pliers & a shop vac.