I have a 1999 F150 with a 4.6 with a coolant leak, I've tracked it down to the heater core return pipe that connects to the back of the intake manifold (after being repeatedly told it has to be the heater core feed tube, which it is not).

My question - this pipe has no o rings or any other type of factory seal. It is a friction fit/press fitting. Is there some type of sealant I should use.

My local Ford service guys suggested red RTV and an open end wrench and just hammer it into place. I did and wrecked the tube.

Before I install this pipe a second time and reassemble the engine, I want to be sure it is installed correctly and is sealed.

Any suggestions on installation and sealing appreciated.

 

lube it up and get it in tight as ya can the braze it on. If it ever fails down the road again heat it up hot enough to melt the braze and put it out. Thats what id do. I wouldnt trust rtv on something as this if it fails your screwed. Bazing is easy enough and would take 10 min to do