Cliff's Quadrajet Parts and Rebuild Kits

General Category => Quadrajet Carb Talk and Tips => Topic started by: GSP7 on January 22, 2025, 09:08:47 AM

Title: brake booster vacuum fitting on back side of quadrajet carb base plate
Post by: GSP7 on January 22, 2025, 09:08:47 AM

What is the proper thread sealant to use on the threads of the brake booster vacuum fitting on back side of quadrajet carb base plate?  If any....

I know I wont use teflon tape

Title: Re: brake booster vacuum fitting on back side of quadrajet carb base plate
Post by: GSP7 on January 22, 2025, 09:43:08 AM

I have some brush on white stuff, pipe thread sealer, think its a teflon paste , or I have some anti seize/thread sealer I use on head bolts etc...

Or ?  Or use nothin' ?

Title: Re: brake booster vacuum fitting on back side of quadrajet carb base plate
Post by: Kenth on January 22, 2025, 10:28:11 AM

Vacuum National Pipe Threads needs no sealant.

Title: Re: brake booster vacuum fitting on back side of quadrajet carb base plate
Post by: GSP7 on January 22, 2025, 02:57:00 PM

 8)

Title: Re: brake booster vacuum fitting on back side of quadrajet carb base plate
Post by: Cliff Ruggles on January 24, 2025, 03:32:22 AM

I use a very small amount of liquid thread sealant (PTFE) on all NPT fittings, NEVER Teflon tape.  The reason I use it as it not only seals the threads is provides some lubricant so they don't bind up and split the casting.  The baseplates drilled and tapped for 1/4" NPT threads are pretty thin and crack easily if you over-tighten the rear fitting......

Title: Re: brake booster vacuum fitting on back side of quadrajet carb base plate
Post by: Kenth on January 24, 2025, 06:18:26 AM

Use lubricant with caution on fuel and vacuum fittings NPT threads as it makes it easier to overtighten and crack the hole.