Hydraulic Fitting Thread Sealer

[WranglerX]

Have a log splitter with leaky control valve.... Spent a few dollars and got a "O" ring kit and rebuilt valve, still leaks (Grrrr).... OK... So now I am going to replace valve.... The issue is someone has been into hydraulics before and nipple between valve body and female connection to ram has a lot of pipe wrench marks.... Going into this with a little trepidation because of unknown things PO may have done...

Main question is what is good thread sealer to use on high pressure hydraulic (NPT) threads.... Not a great fan of PTFE tapes... So its probably going to be a liquid sealer .... Any suggestions...

 

[MF RED in MT]

I know others will have their favorite thread sealer, but for me it's Loctite 545 Thread Sealant".

KC

 

[MarshSt]

Loctite 567 is what we use (Arial Lift Equipment OEM) for all hydraulic threaded fittings.

SM

 

[/pine]

FWIW...NTP threaded fittings etc. are really only meant to be used once...the taper of the thread make a seal when tightened by molding together...every time they are re-used they have to be tightened slightly beyond the previous point they were torqued at....

 

[kennyd]

FWIW...NTP threaded fittings etc. are really only meant to be used once...the taper of the thread make a seal when tightened by molding together...every time they are re-used they have to be tightened slightly beyond the previous point they were torqued at....

^^^
This.

Replace fittings if you can.

 

[WranglerX]

So according to above information I have to replace a $200 hydraulic cylinder because female NPT fitting WELDED on cylinder is not to be reused.... Or I have to actually live with leaking valve for the time I own the splitter.....

 

[ptsg]

So according to above information I have to replace a $200 hydraulic cylinder because female NPT fitting WELDED on cylinder is not to be reused.... Or I have to actually live with leaking valve for the time I own the splitter.....

You replace either the male or the female fitting, whatever is easiest to do. Don't need to do both.

Although, I've reused NPT fittings in the past like 3 or 4 times without any issues. Sometimes with Teflon tape, other times with some hydraulic sealant I have. Can't remember the maker and the label is gone unfortunately.

 

[WranglerX]

You replace either the male or the female fitting, whatever is easiest to do. Don't need to do both.

Although, I've reused NPT fittings in the past like 3 or 4 times without any issues. Sometimes with Teflon tape, other times with some hydraulic sealant I have. Can't remember the maker and the label is gone unfortunately.

I intended to replace nipple (Sched 80) and valve, but can not do anything about the welded female coupler on hydraulic cylinder other then hope its is not distorted to much to not seal, that is all about why I asked the question about sealer....

 

[oldnslo]

If using a loctite type sealant you must remove all of the oil possible to get them to seal properly. If real oily the loctite will not cure.

I have used both Teflon paste and loctite. Just be careful not to over tighten and crack the valve casting. Do not ask how I know this can happen

 

[kennyd]

Also,
Try to let any sealants dry/cure for 24 hours before applying pressure to the system.