Coolant temp sensor intake adapter?

[newoldscottsdale77]

I cannot find an adapter to install a coolant temperature sensor in my edelbrock performer intake. I read here that i needed a 1/2" male pipe thread to a 3/8" female fitting. I bought the fitting but my sensor wont screw past 4 threads, they seem to be off just a little. What am i missing? The sensor has no abnormalities like burres or damaged threads. Fitting was from homedepot.

 

[tRustyK5]

pipe thread is tapered...so the farther in you screw it the tighter the interference fit becomes.

 

[snowdriver]

that is correct,pipe threads are tapered,and get tighter as you screw em in,put a few wraps of teflon on it and you are good to go