RTV cement application

by Had Robinson

Glop it on and screw the pieces together....

This is NOT how to do it.  Here are the specific directions from Permatex on the CORRECT way to apply it:

Surfaces should be clean and dry.  Apply a continues 1/16" to 1/4" (2 to 6mm) bead of silicone to one surface, surrounding all bolt holes.  Assemble parts immediately while silicone is still wet.  Finger tighten until material begins to squeeze out around flange.  Let dry for ONE hour THEN tighten to torque specifications.  Allow 4 hours to fully cure before filling with fluids or returning to service.

It is best to use one's finger to apply the cement.  Use of a nitrile glove is recommended.  For small engines like a paramotor we rarely need a 1/4" (6mm) bead.  A 1/16" (2mm) bead is usually MORE than adequate.  Case halves, for example, need even less lest the cement bulges out inside the crankcase, comes loose, and potentially clogs an oil port!

There are exceptions to the "no glop" rule and they are noted in these pages.

Turkey Vulture