Teflon Tape

57fury440

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Does the Yellow Teflon tape work for gas lines and fittings? It says for natural gas on the package. Thanks in advance.
 
Don't use it on gas lines. The little shards can get in the needle and seat and cause all sorts of havoc.

Permatex makes a great Teflon thread sealant that works great for that application.

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IF you are going to use "tape" have to wind it in the correct direction so it really seals things. Not an issue using the "in a tube" version, though.
 
If it a flared line fitting the double flare seals to the fitting. The threads don't make a seal so leave threads dry. And if you seal the threads it can still leak by the nut on the line.

If it's the nut that screws to the carburetor the gasket makes the seal to the carb so leave threads dry.

What does this connection look like?
 
tape goes on NPT fittings ( tapered pipe thread )....most fuel lines are flared fittings, where the flare on the end of the tube is forced against the conical seat at the bottom of the female fitting, that's where the sealing takes place...wrapping teflon tape around the threads of the male fitting that spins on the tube doesn't seal anything at all...same goes for brake lines...i cant think of anything on the fuel system of our cars that uses pipe thread
 
Don't use it on gas lines. The little shards can get in the needle and seat and cause all sorts of havoc.

Permatex makes a great Teflon thread sealant that works great for that application.

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Agree. Don't use on fuel line. Heck - I never use it anymore on anything. Only a teflon sealant such as this one. I use a Loctite version - 567.
 
I have never used it on fuel lines. It was more of a "just in case" question, if I should have some on hand. Once again, thanks for everyone's replies. This is a great website with a lot of good people on it.
 
i cant think of anything on the fuel system of our cars that uses pipe thread
Those HP Carter fuel pumps use an NPT to flare fitting. I've used them a few times myself as have many others. Some of the 50's fuel pumps have that NPT fitting too. Then there's any add-on electric pumps and even a few fuel filters too.

But yea, except for those, all the fittings are flare or hose.

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Should it be used or NOT used on pressure hoses like Power Steering pump to box fittings?
Not sure what kind of fitting those are. But if they are a npt style thread use the teflon style sealant. If you are referring to the flared fitting, nothing goes on them.

You don't want to get teflon tape pieces in any fuel or hydraulic system. If you want to use it on a water pipe or air line, no issue. I would not - I would use teflon tape in those applications also.
 
What kind of sealer on Engine block Drain plugs ?
 
What kind of sealer on Engine block Drain plugs ?
Seems like the old-line techs would use the #2 Permatex to put a hin coat around the edges. Probably for lubricant and ease of installation than "dry"?
 
As to Teflon tape, a Holley engineer advised AGAINST using it on carburetor castings. He termed it "an OTC thread puller".

I fully realize that many of us like to do things "better than the factory did", in restoration and vehicle repairs. Teflon tape/sealer can fall in that orientation easily. But in some situations, its presence can be such that it can become a Band-Aid fix, which is very visible. Which can make it a very visible indicator that "something else is not as it should be", to me.

I know there are some things the factory did that look "Mickey Mouse" and such, BUT those same things also were easy to make happen and lasted for well past 75K miles of use. Which then makes those things look pretty good, all things considered.

One reason the sealant is a better deal than the tape is because there is a way to apply the tape to the desired fastener. The tape must be applied to the nut so that its "direction of wrapping" coincides with the nuts rotation as it is screwed into the casting.

If done correctly, the tape stays put as it will not unwind due to the direction of rotation. It can be a work of art, but if not done correctly, frustrations and more trouble than it is worth, by observation and experience. Learn to use it well AND use it only where needed!

CBODY67
 
IF you have a leak through the threads of the oil pan drain plug, you need a new drain plug. Some auto supplies have "oversize" drain plugs for worn threads on the oil pan internal nut.
 
What kind of sealer on Engine block Drain plugs ?
I assume you mean the coolant drain plugs that go into the water jacket. That Teflon sealant I mentioned would work great and so would #2 Permatex.

No sealer. The washer is the sealer.
I think you are referring to the oil pan drain plug, which does seal with the washer, and not the block coolant plugs.
 
IF you have a leak through the threads of the oil pan drain plug, you need a new drain plug. Some auto supplies have "oversize" drain plugs for worn threads on the oil pan internal nut.
The threads on an oil drain plug are straight threads, commonly 1/2x20 from mid 60's on up. So the threads will leak by design. The sealing is done by the washer between the drain plug head and the oil pan.
 
I like to use anti-sieze on engine block drain plugs so they will come out years later. Do not crank them down like a lug nut. They are pipe threads and will seal with nothing on them.
 
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