Tape or Paste fittings

[Gary Fowler]

Another thing I laugh at is the fable that tape will stop up the hydraulic filters. Must be some awful small filters that those folks were using. Some industrial control valves have some small orifices that could get clogged if enough tape were to be forced into them. I don't think a tractor has such small orifices to content with and the pump is a positive gear pump which isn't going to even know when a small piece of tape that might get into the system would pass thru. As soon as the oil and the debris reaches the reservoir, it isn't going back out without going thru the filter so its journey ends there.
I wouldn't sweat if using any thread sealant on any NPT threads, if don't correctly no ends will be loose and debris only comes in the picture when the threaded fitting is removed and not cleaned properly. The same holds true for paste which most times is applied too generously.

 

[J_J]

I simply don't understand why people don't use the recommended sealant/locker.

Loctite has been making the sealant for many years .

Product search - Henkel

NPT fittings were never meant to be used over and over. The threads are reshaped every time you tighten and remove the fittings.

It is a 50/50 toss up whether to use tape or paste, but since I know better, I use the Loctite 542 most of the time or the fast cure..

 

[jcummins]

I simply don't understand why people don't use the recommended sealant/locker.

Loctite has been making the sealant for many years .

Product search - Henkel

NPT fittings were never meant to be used over and over. The threads are reshaped every time you tighten and remove the fittings.

It is a 50/50 toss up whether to use tape or paste, but since I know better, I use the Loctite 542 most of the time or the fast cure..

In my case... I had no loctite 542...and it's on the expensive side compared to Real-Tuff. And it says right on the label can be used on hydraulic systems.... So loctite isn't the only sealant out there.

And just a dab will do ya.

 

[J_J]

I never said it was the only sealant.

I would use spit if it was all I had, and it don't cost anything.

 

[/pine]

I never said it was the only sealant.

I would use spit if it was all I had, and it don't cost anything.

And would probably be just as affective with quality NTP fittings...(at least the first time they were tightened...)

 

[Deere Dude]

A FUNNY TO ME STORY.
As a pipe-fitter apprentice in 1980 about, I would work with a few journeymen who complained when I would 242 or Teflon paste joints and reef on the joints fairly hard. I am physically a big boy so they were concerned I would over-tighten fittings and use Loc-Tite on those fittings so they couldn't get the fittings apart, so they would harp at me about that.

I was given the task to install about 500 feet of mostly 2" pipe airline headers going to many different places.

I finally heeded their advice and used tape and didn't reef on the pipes as hard as I usually did.

After a week of construction I turned the air on to the system. It sounded like I was in a rattlesnake pit with so much noise. I had air-leaks all over the place.

Guess who had to redo the leaky pipes? It sure wasn't them. I had to redo almost every joint in the system and this time I used either Teflon paste or 242, I don't remember. This time I did it my way.

But I know enough now to use what I know works for me, and tape generally isn't it. Although I did get a bunch at Harbor Freight for home use and use it when leaks aren't critical.

 

[muddstopper]

I simply don't understand why people don't use the recommended sealant/locker.

Loctite has been making the sealant for many years .

Product search - Henkel

NPT fittings were never meant to be used over and over. The threads are reshaped every time you tighten and remove the fittings.

It is a 50/50 toss up whether to use tape or paste, but since I know better, I use the Loctite 542 most of the time or the fast cure..

JJ is correct. The tape is a sealer, but it acts like a lubricant. The lubricating properties of the tape can cause overtighting which deforms the threads and cause more leaks than it fixes. Face the fact, just how many times have you personally gotten the biggest wrench you can find to tighten a pipe fitting. Oever tighten, stretch the threads and leaks will follow. Another thought, yo have to buy the sealer either way,why not just buy the stuff specificly made for NPT hydraulic fittings?

 

[muddstopper]

I simply don't understand why people don't use the recommended sealant/locker.

Loctite has been making the sealant for many years .

Product search - Henkel

NPT fittings were never meant to be used over and over. The threads are reshaped every time you tighten and remove the fittings.

It is a 50/50 toss up whether to use tape or paste, but since I know better, I use the Loctite 542 most of the time or the fast cure..

JJ is correct. The tape is a sealer, but it acts like a lubricant. The lubricating properties of the tape can cause overtighting which deforms the threads and cause more leaks than it fixes. Face the fact, just how many times have you personally gotten the biggest wrench you can find to tighten a pipe fitting. Oever tighten, stretch the threads and leaks will follow. Another thought, yo have to buy the sealer either way,why not just buy the stuff specificly made for NPT hydraulic fittings?

 

[k0ua]

So guys are we saying here, we could all save a bunch of money and not buy tape, paste or sealer, and just hawk up a big lugey and use that!:laughing: Excuse me while I clear my throat!

 

[J_J]

Spit is one thing, but a thick green pasty, nasty, lunger is just plain nasty and might clog the hyd system.

GROSS.

 

[BlacknTan]

I've always used the Loctite sealant designed for the job.

But, I hate to do things over, so don't go by me!

 

[bigdeano]

Can you use the 542 on plastic? 242 is for metal only, will destroy some plastics as I found out the hard way.

 

[J_J]

LOCTITE® 542 is designed for the locking and sealing of metal
pipes and fittings

 

[davrow]

why not just buy the stuff specificly made for NPT hydraulic fittings?

Because until I joined TBN I had no idea whatsoever that such a product existed. My home plumbing needs always gladly accepted Teflon tape - I thought it was as universal as duct tape and a bigger hammer.

 

[ber72564]

Sorry to jump in here, Question 3/8" ORB female to ORB Male AG type ISO QD to Hydrauluic hose max pressure 1500 PSI. Tape or Not?

 

[Furu]

Sorry to jump in here, Question 3/8" ORB female to ORB Male AG type ISO QD to Hydrauluic hose max pressure 1500 PSI. Tape or Not?

ORB fitting never, ever tape. The O ring is the seal and thread is straight SAE and needs no lube

 

[ber72564]

Thanks that is what I thought.

 

[CJONE]

Another thing I laugh at is the fable that tape will stop up the hydraulic filters. Must be some awful small filters that those folks were using. Some industrial control valves have some small orifices that could get clogged if enough tape were to be forced into them. I don't think a tractor has such small orifices to content with and the pump is a positive gear pump which isn't going to even know when a small piece of tape that might get into the system would pass thru. As soon as the oil and the debris reaches the reservoir, it isn't going back out without going thru the filter so its journey ends there.
I wouldn't sweat if using any thread sealant on any NPT threads, if don't correctly no ends will be loose and debris only comes in the picture when the threaded fitting is removed and not cleaned properly. The same holds true for paste which most times is applied too generously.

You are 100% correct, the filters do not care and I have had a gear pump [a large one!] eat a shop rag with no damage. Come to think of it, the guts out of a filter head, the top strainer assembly, many various small parts, most of these pumps survived. Now the parts that they ate were usually stuck in the valve body. But the one that ate the rag was wound in the pressure control so tight that it had to be taken apart and cut out! what usually happens is the tape because of careless use ends up stuck in a relief valve, compensator port or pilot shift port in a valve and that causes all kinds of problems. I use both and have had 0 problems and MAYBE 5 leaks out of 100's of fittings. A lot of these are on systems that are 5000-6000psi. When we first started I was told not to use tape and had many leaks with just thread sealant so that went out the window real quick. You can't have problems like that and expect customers to be understanding when it happens more than once. CJ