thread sealant on plastic 90s

[Chris_B]

I have to replace the plastic 90s that come out of the intake manifold (male pipe thread on one side, slip joint on other side).  Do these plastic 90s need thread sealant?  If so, what type of sealant is best?

[Engine Nut]

Just use regular TFE Pipe Thread Sealant on those threaded fittings.

[Woodski]

@Engine Nut:  Question - do the plastic 90's threads deform enough when torqued to provide a seal?  Thanks.

[Engine Nut]

On ‎11‎/‎30‎/‎2017 at 9:21 AM, Woodski said:

@Engine Nut:  Question - do the plastic 90's threads deform enough when torqued to provide a seal?  Thanks.

They are tapered like any pipe thread so when they are tight they seal.