is not teflon tape good enough for pipe thread

[vector1]

had some coolant seaping around inlet and optional plugged inlet on water pump. both are 3/4" pipe thread and i used teflon tape. guess the teflon tape is not good enough with pipe thread, maybe go the rtv route. puddle formed over the course of couple days so it wasn't a gusher.

this is with npg so maybe it is a little more seapage prone or eats teflon.

nothing like the suspense between finding a puddle on the floor and discovering where it came from.

[xracerbob]

I've used this stuff and it seems to work very well:
http://store.summitracing.com/egnsea...17374&D=317374

[vettestr]

As you know pipe threads are a course and tapered thread with an increasing interference fit. If a softer material plug (like brass) is being inserted into a cast iron water pump that also helps it seal. Teflon tape installed correctly does seal if no issue with either the male or female side has burrs or defects. I like the Teflon paste because it is easier to make a clean and neat install for me anyway.

[wtm442]

Remove the plug and chase the female pipe threads with a tap. Clean plug threads with a wire wheel. If the threads are damaged, get another plug. Wrap teflon tape around threads tightly about 3 turns. Work the tape into the threads by turning the plug between your thumb and forefinger.

Most pipe plug leaks are due to poor quality threads or improper application of thread sealant.

[vector1]

i am going to use some locktite stuff on another radiator fitting i'm changing out and maybe these two. it's kinda funny, there is a couple stains from the same fittings from previous owner dyno use only, so it is not my technique i don't think. i've never seen this before or had problem with pipe threads leaking. the housing and one fitting are al, the plug is steel. guess i'll have to put the hammer to 'em.

thanks for the input.

[RedBarchetta]

Originally Posted by vector1

i am going to use some locktite stuff on another radiator fitting i'm changing out and maybe these two.

I would be real cautious about using Loctite on any radiator component. The tanks are aluminum/brass as well as the fittings. You could ruin either component if they are on too tight.

Better to use a liquid teflon sealant/paste (Permatex sells it in a tube).

-Dean

[tkb289]

This may be a bit 'old school' but try pipe dope. It comes in a stick, looks like a fat crayon. Make sure both parts are clean and dry. Just rub it on the threads of the male part, till the threads are full then assemble and wipe off the excess. If you can, wait a day or so to let it firm up. Plumbers use this all of the time and it's rated for a variety of liquids and temperatures, usually listed on the label ... and it is also removable.

- Tim

[vector1]

locktite makes a thread sealant.

[Chaplin]

Originally Posted by vettestr

As you know pipe threads are a course and tapered thread with an increasing interference fit. If a softer material plug (like brass) is being inserted into a cast iron water pump that also helps it seal. Teflon tape installed correctly does seal if no issue with either the male or female side has burrs or defects. I like the Teflon paste because it is easier to make a clean and neat install for me anyway.

Ditto. Teflon paste is the way to go.

[Rick 427 Cobra]

I don't know about "putting the hammer to it". Tapered threads can easily split an aluminun hole. Maybe it already has if common sealers are not working.

[mrmax]

loctite pst works well, but if it must not leak cotton string wicking and rector seal #5 pipe dope. get the wicking from commercial plumbing supply house, or old skool plumber.the larger the pipe size the less likley teflon alone will seal.especially if dissimilar metals.

[maurice19]

Like Tim said,

The plumbers I knew that never had leaks used teflon tape for lubrication and also coated the threads with pipe dope.

Works for me too

Maurice

[nevermind65]

Teflon paste. It will never leak again.

[Speedysnake]

A common problem with using teflon tape is putting it on backwards. Remember the leading edge should be on the male fitting so it doesn't catch in the female threads and unwrap.

[vector1]

checked this morning, looks like the paste is holding. tape probably never had a chance, just scrubbed off as the fittings were installed.

[LRcobradreamer]

What do you guys use on the fuel lines pipe threads?? Such as at the fuel pump ports.

Lee

[speed220mph]

We use Teflon pipe dope on race engines with satisfactory results. The problem with tape is if it's used improperly when sealing fuel or oil lines, i.e., taping the leading two threads, little pieces shear off and get into the system. This may plug oil galleys or fuel passages. Consequently,the FAA restricts it's use.

[Snakebit]

Try ARP Thread Sealant. Comes in white tube. I've used it on everything, coolant, fuel, and oil fittings, no leaks.

[rdc767]

I've been fighting a water leak on my cheap pro comp water pump. Its been leaking around the water inlet 3/4" pipe. I thought tape was the best way to seal it but it didn't work. I even tried the thicker yellow gas tape and the thicker pink tape. It didn't work. After reading this thread I tired Teflon white pipe paste and that did the job. Thanks
Ron

[vector1]

i'm still fighting a small coolant leak, about a 2" round drip overnight, size of a quarter in a few hours. i can't find it for the life of me. i clean it up and come back and there it is again. i feel around all the joints and can't find anything wet. someday. has to be around the electric water pump somewhere. kind of a phantom leak.