Looks like the plastic molded drain nipple is broken off flush with my evaporator housing on my '78 F100 with factory air.
Does anyone know of a fix for this? I thought about trying to thread a pipe nipple in it, but thinking it will stick up too far on the
inside and not let it drain properly.. Obviously a replacement housing would work, but that's not possible at this time. Any suggestions?

 

Just leave it, it just drains to the ground regardless if the nipple is there or not.

 

You would think so, but the condensate is running back to the firewall, then running to the inside of the firewall and running down to
the floor board..

 

I'm assuming the worst case scenario that you don't have the broken off nipple. If you have it, try some appropriate glue. You're probably correct about the threaded pipe nipple not allowing for correct drainage. You could use another piece of appropriately sized plastic pipe with glue or get a flanged fitting and use glue or screws on the flange. Check your local supplier of plastic pipe like hardware or home improvement stores. If I'm remembering correctly, my '76 F250 has a one way rubber hose on that nipple. The hose allows condensate water to drain, but won't let hot air into the evaporator case.

 

Yes, it was broken off before I got the truck.. I was even thinking about a plastic gas can nozzle... they have a flat sealing surface, and then the spout can be the drain..

 

Found this on Amazon.. I couldn't find any dimensions on it... Hope it
will work!