I installed a new 440 Source aluminum water pump housing on my 440 with a new aftermarket temperature sending unit. The sending unit leaked through the threads. I replaced the new sensor with my old stock unit and it also leaks. The leak is very small but it's still a leak. Can I put anything on the sending unit threads such as teflon tape or teflon paste (pipe dope) or will a sealant block the sensor's ground? Would a small rubber o ring work?
Thanks for any help.