Hey, i got an electric Autometer oil pressure guage for my car. When i installed it, i used a T fitting with the sender on the back and the sending unit on the top ..the other going to the block. I installed the fittings using Rectorseal to prevent leaking. Well, this worked for about a week and now it is leaking from where the fitting meets the block. What kind of sealant do i need to seal the sending unit????? Thanks!