Can someone who has professional knowledge tell me when and when not to use teflon tape? As far as I know, you can use it on black gas pipe fittings, water plumbing, and any steel fitting. I was told never to use it on brass because brass is a soft metal and the threads will "conform" together upon tightening. Also I was told never to use it on any brake line fittings because all brake fittings are compression fit. Lastly, I was told never use teflon on AN fittings because the threads interlock creating an airtight seal. Am I correct on this and is there anything else that should be included here???
When and when not to use teflon tape?
- Thread starter d0n_3d
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Good question, as many folks don't know which Teflon Tape is meant for what applications. I've found that it's not a good idea to use the teflon tape on any type of a sensor that grounds its self through the threads. If you put too much tape on it, there is a chance that the tape can prevent the sensor from grounding properly. I use pipe dope on these. Don't use Regular Teflon Tape (Blue Plastic Case) for any gasoline connections, as it will melt and start leaking eventually. For gasoline use the Teflon Tape in the Red Plastic Case or the Pipe Dope pictured below. The Yellow Cased Teflon Tape is for use with Natural Gases. Hope this helps.
The tape that's in the blue package is for regular plumbing in a water environment. The red is for use with solvents while the yellow is for use with gas............as in natural gas.
See the pics below.
:smile:
The tape that's in the blue package is for regular plumbing in a water environment. The red is for use with solvents while the yellow is for use with gas............as in natural gas.
See the pics below.
:smile:
interesting.You also do not want to use it on the knock sensor!! modifies the accoustic characteristics!!
i use this **** on almost everything.. never had a problem.
Lee Thompson
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Teflon tape
First off, teflon tape or liguid pipe dope are neither considered sealants. They are lubricants. The idea is for the threads to engage smoothly. When using either DO NOT apply to the first 1-2 threads as to keep it out of whatever you are running through the system. Brass is soft enough that the threads will conform and seal. With some kind of dope, brass will go together and come back apart easier. NPT threads are tapered (Male and female). If the threads have been threaded and tapped the correct depth and the EDGE is sharp--the better they will seal. I'm not saying that some of the liquid dope won't set up and help seal--just that it's purpose is to lube. Dope on a flared fitting is about as usless as a screen door on a submarine. That's all I know about that.
First off, teflon tape or liguid pipe dope are neither considered sealants. They are lubricants. The idea is for the threads to engage smoothly. When using either DO NOT apply to the first 1-2 threads as to keep it out of whatever you are running through the system. Brass is soft enough that the threads will conform and seal. With some kind of dope, brass will go together and come back apart easier. NPT threads are tapered (Male and female). If the threads have been threaded and tapped the correct depth and the EDGE is sharp--the better they will seal. I'm not saying that some of the liquid dope won't set up and help seal--just that it's purpose is to lube. Dope on a flared fitting is about as usless as a screen door on a submarine. That's all I know about that.
salvageV6
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What he said. 
First threads get nothing then a dab on the next few threads, I even read somewhere not all the way around them either.
I always overdo it however, luckily I've never plugged up a gauge or line or anything....
Only used on NPT type fittings, and I think many GM sensors have their own goop or sealant on them anyway the dry colored stuff.
Not used on any straight threads I believe there's more specialized stuff for water pump bolts and head bolts.
First threads get nothing then a dab on the next few threads, I even read somewhere not all the way around them either.
I always overdo it however, luckily I've never plugged up a gauge or line or anything....
Only used on NPT type fittings, and I think many GM sensors have their own goop or sealant on them anyway the dry colored stuff.
Not used on any straight threads I believe there's more specialized stuff for water pump bolts and head bolts.
Get ahold of Ted A. on this subject.
I know you can't use teflon with diesel fuel.
Billy T.
gnxtc2@aol.com
I know you can't use teflon with diesel fuel.
Billy T.
gnxtc2@aol.com
Rodney87GN
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On AN fittings, or any type of other flared fitting, the seal is in the flare on both mating ends of the tube/fitting, and NOT the threads.
Use teflon/sealer on NPT fittings only, where the seal is in the threads.
Opinions vary. I do not use teflon tape on gas pipe fittings except 2" and larger pipe. I make sure my dies are in great shape and adjust them for proper engagement. The important thing is to study the sealing surfaces you are dealing with and go from there. I do use teflon pipe sealer in areas that some would question, but this is from years of experience of dealing with things and found that doing it has a more predictable outcome. Using teflon tape on threads that have absolutely nothing to do with sealing (AN flare fittings, gas appliance connectors, gas unions, ect) is not neccesary and I see it all the time in homeowner/handyman's work.
To use teflon tape all the time is just not necessary. Plastic fittings for example should not be used with teflon tape as it will cause you to overtighten and the fitting may break over time from the stress.
To use teflon tape all the time is just not necessary. Plastic fittings for example should not be used with teflon tape as it will cause you to overtighten and the fitting may break over time from the stress.
You also do not want to use it on the knock sensor!! modifies the accoustic characteristics!!
You are right.........and I need to take a look at the knock sensor I put in not too long ago. Don't remember if I put some tape on there or not, just so used to using it.
Turbo Indian
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TexasT
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Back to topic, I wanted to reiterate the caution to be careful of the amount and location of the tape when in use. 2-3 turns around the threaded portion and the first two to three threads need not be covered to prevent the tape from getting into the system.
I do prefer a good pipe dope when doing residential type plumbing. Rector seal number 5 is my preference but like an oil thread this varies with the user. Same rules of application with the dope. Too much is not 'just right' and it makes a mess.
plain and simple ,use it on everything...
LA-CO: Product Detail - LA-CO LOC® - Anaerobic Pipe Thread Sealant
LA-CO: Product Detail - LA-CO LOC® - Anaerobic Pipe Thread Sealant
boostedturbotom
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