For applications such as sending units or screw in type switches.
Thread Sealant or Teflon Tape?
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I used teflon tape on a coolant temp sending unit in the top of my intake manifold. The tape made it darn near impossible to get the sending unit screwed in and seated all the way. I only used about 2 turns of the tape around the threaded end of the sending unit but it still made it a very tight fit.
If you can get away with it, I say use thread sealant.
If you can get away with it, I say use thread sealant.
+1 thread sealant but, us a non harding type.
Light application of teflon filled thread sealant.
Tape is for water pipe. Use sealant for the far-more precise tapered threads found in motor vehicles.
Which one won't affect the electric currant if it's an electrical guage?
Originally Posted By: Kiwi_ME
Tape is for water pipe. Use sealant for the far-more precise tapered threads found in motor vehicles.
Kiwi, I don't agree with that. While I do agree that tape always isn't the best choice, it has nothing to do with tape only being for water. Also, an NPT thread (for example) should be the same on a vehicle, vs some other application, except for the depth tapped.
I believe that's the purpose of having a standard.
Tape is for water pipe. Use sealant for the far-more precise tapered threads found in motor vehicles.
Kiwi, I don't agree with that. While I do agree that tape always isn't the best choice, it has nothing to do with tape only being for water. Also, an NPT thread (for example) should be the same on a vehicle, vs some other application, except for the depth tapped.
I believe that's the purpose of having a standard.
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I like the Permatex Pipe Sealant. I recently did a natural gas project with about a dozen inch pipe joints, some of which I left a little on the loose side to get a tee pointed in the right direction. Went over every joint with soapy water after I was done and didn't see the first bubble.
Originally Posted By: Chris142
Which one won't affect the electric currant if it's an electrical guage?
Depends on what type of sensor/switch we're looking at, but this is a good point.
You'll want to use something like Permatex Pipe Sealant- particularly if you're looking at a 1-wire switch or sending unit that grounds through the tapered pipe threads. Thread tape can prevent this type of switch from grounding properly through the threads, but liquid teflon thread sealant generally works fine.
I've also put these types of sensor in with just antisieze on the threads in the past. It isn't the 'right' way, but it worked. And there were definitely no problems with grounding.
Which one won't affect the electric currant if it's an electrical guage?
Depends on what type of sensor/switch we're looking at, but this is a good point.
You'll want to use something like Permatex Pipe Sealant- particularly if you're looking at a 1-wire switch or sending unit that grounds through the tapered pipe threads. Thread tape can prevent this type of switch from grounding properly through the threads, but liquid teflon thread sealant generally works fine.
I've also put these types of sensor in with just antisieze on the threads in the past. It isn't the 'right' way, but it worked. And there were definitely no problems with grounding.
All teflon tape is NOT the same.
Some cheap stuff is crud!
But good stuff is rated for solvents, oil, etc..
Like mentioned, you may need a good electrical ground, and tape or standard sealant may not be best.
Permatex #2 is a good thread sealer for engine fittings.
Some cheap stuff is crud!
But good stuff is rated for solvents, oil, etc..
Like mentioned, you may need a good electrical ground, and tape or standard sealant may not be best.
Permatex #2 is a good thread sealer for engine fittings.
I have gave up on tape and like the liquids. Permatex liquid Teflon, the other permatex pipe sealant that looks a bit like a heavy gasket shellac, & a product that goes by the name of Rectordseal. I never brush sealant on the first couple of threads.
Originally Posted By: onion
+1 on the permatex #2 suggestion.
How about the Permatex High Temp Thread Sealant? It's suggested uses are Head bolts into through holes, oil PSI sending units and sensors, oil and coolant lines, fuel fittings, rear axle fill plug, brake and power steering fittings
+1 on the permatex #2 suggestion.
How about the Permatex High Temp Thread Sealant? It's suggested uses are Head bolts into through holes, oil PSI sending units and sensors, oil and coolant lines, fuel fittings, rear axle fill plug, brake and power steering fittings
Didn't know there was such a thing, but I imagine it'd work fine.
I don't think I'd use it on brake and power steering fittings though. Not sure exactly what type of fittings they have in mind, but most of these aren't suited to thread sealant.
I don't think I'd use it on brake and power steering fittings though. Not sure exactly what type of fittings they have in mind, but most of these aren't suited to thread sealant.
Pipe threads are a particular type of tapering thread that seals by the threads tightening up against each other. They are the only style of fitting that needs thread sealant. They were historically used with water pipe. Usually a minor leak is no problem and quickly corrodes shut.
Brake and power steering in the past were flare fittings. Newer power steering joints often use O-Rings. Such joints don't need any sealant of any kind.
Brake and power steering in the past were flare fittings. Newer power steering joints often use O-Rings. Such joints don't need any sealant of any kind.
labman - Obviously, you never heard of a small block Chevy.
Head bolts had to be sealed.
Water pump bolts also.
And plenty of other engines need bolt sealing that are not pipe threads..
Head bolts had to be sealed.
Water pump bolts also.
And plenty of other engines need bolt sealing that are not pipe threads..
I'm all thumbs when wrapping threads with tape. I prefer the white Teflon sealant.
For head bolts and other fasteners that live in liquid, I use Permatex No. 2.
For head bolts and other fasteners that live in liquid, I use Permatex No. 2.
Originally Posted By: oilcoholic
For applications such as sending units or screw in type switches.
ARP Teflon thread sealer is what I use. I haven't used Teflon tape in years. lol
For applications such as sending units or screw in type switches.
ARP Teflon thread sealer is what I use. I haven't used Teflon tape in years. lol
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