"Teflon" Thread Sealing Tape ?

[Robert11]

Hello,

Working on my snowblower, early for a change, for next season.

Regarding the thread-sealing tape one uses to seal plumbing, or other, threads from leaking: (tempted to call it Teflon tape, but doubt that it really is)

Have an oil drain tube on my snowblower. It's steel, while the engine block is AL.

The tube, being screwed into the engine block, gets really, really, hot during engine usage.

I had the tube out, and when I put it back I wrapped the threads with this tape. (No thread on originally when new)

It "seems" to be leaking very, very, slightly now.

Question: Not sure what temp the tube really gets up to during use, but it is definitely too hot to touch by hand. Is this type of tape good for the likely temp's that it is probably seeing ?

Is this kind of tape generally used for an application like this, or is the steel tube just screwed right into the AL block ? If so, wouldn't it leak even more ?

Other approaches ?

Thanks, Bob

[JoeSpareBedroom]

Good question. If you don't get a clear answer here quickly enough to continue with your work, call an auto parts store. I've never checked the packaging to see if teflon plumbing tape has a recommended temp range. But, water pipes certainly don't get as hot as the metal you're dealing with. There has to be something better for this purpose.

[David Martel]

Robert,

The tape should not be necessary to get a drip free seal. The threads are tapered to prevent dripping. Try assembling, without the tape, when the engine and plug are at room temp. Check your manual for torque suggestions. Teflon tape should be very heat resistant. Some thread tape is not teflon. Look for PTFE.

Dave M.

[Clark]

"Robert11" wrote in news:i-2dne3hM6ttzQLbnZ2dnUVZ [e-mail]:

IME it's not uncommon to use thread tape just about any time you have tapered pipe threads. The "magic" ingredient is teflon which is fairly temperature stable. Be careful not to wrap the tape on the first thread so you don't inadvertantly put scraps of the tape into the engine since they could plug an oil port.

Other approaches include pipe "dopes" which contain teflon or copper or other metals along with lubricants. The pipe dope containers may have a specified temperature range. They are generally available anywhere plumbing supplies can be purchased. If you use a dope, make sure not to contaminate the oil.

As a side note, some folks are recommending the use of pipe dope and thread tape together. It seems like overkill but it for me in getting some damaged threads to seal.

[Pete C.]

Teflon (tm) a DuPont brand name for their PTFE. Teflon / PTFE has a working temp well above the couple hundred degrees that a small gas engine should be getting to. Pipe threads are tapered for sealing so just tighten the pipe a bit more.

[Greg]

I just sweated off a 3/4" copper pipe with a threaded end, I had used teflon tape on threads, after I got solder apart I cooled it down and went to clean up threaded end and found teflon still perfect, I can garrenty that copper was hotter then your engine is.

[Stormin Mormon]

I've found Permatex #2 non-hardening works nicely in cases like this. Dab a little onto the end of the pipe, and thread it back in.

Careful not to get the black goop on hands or clothes, it doesn't want to come out. Alcohol dry gas helps get it off skin.

[valvejob]

You can add more tape or tighten it or both. On faucets, you use more tape so you can position the faucet with handle up. Nothing wrong with using 3 layers.

[tnom]

Teflon tape is the correct term if it uses PTFE

Tapered pipe threads should always use some sort of sealant.

Teflon tape is great for high heat applications like the one you describe. Just wire brush to remove particles.

Wrap the tape appropriately so that it won't unwind when screwing the pipe in.

[tnom]

Speaking of faucets............It is a good idea to take all threaded parts apart on new plumbing fixtures and reassemble with Teflon tape. This makes all future repairs a breeze.

[professorpaul]

I agree that BOTH pipe dope and tape would seem to be overkill, but in stubborn cases, it works just fine. Check your auto parts store for "Permatx" pipe/thread dope. Two versions -- permanent and non-so- permanent. I keep the 2nd around for such cases. The other stuff sets up pretty hard, and is very difficult to get apart again. The Permatex products seem to work much better than the usual gray pipe dope. Get a bigger hammer....

[barry]

Hot to the touch, but not that hot, really. Teflon tape will handle it.

Be fussy to not have little shards of tape getting loose inside.

M'self, I'd probably put a suitable pipe nipple into the block, with hardening dope, and use tape a/r at a cap. All this to make it as easy as possible to capture the drained oil. Two wrenches a/r.

HTH, J

[Oren]

The Permatex product mentioned is a perfect solution - imo. (Oil - heat - two materials and vibration) This will solve the leak.

The non-hardening type will allow the metal pipe to be removed if needed. It will take the heat, reduce vibration of the pipe. likely the cause of the leak)

Check an auto parts store.

-- Oren

"The voices in my head may not be real, but they have some good ideas!"