diesel pipe dope thread sealant

SWMaint.corp · Post by **SWMaint.corp** » Tue Oct 07, 2014 12:53 pm

What is everyone using for pipe dope on diesel or bio diesel I have been having problems sealing threaded flanges sealing passing air test but seeping fuel we use Teflon tape and blue magic dope. Is there something others use that don't leak?

bigbadjohn · Post by **bigbadjohn** » Thu Oct 09, 2014 10:34 pm

Teflon tape wicks petroleum.

Post by **tankgenie** » Fri Oct 10, 2014 1:11 am

What is Wick's petroleum? We are having similar issues SWMaint.

Post by **CherokeeUST** » Fri Oct 10, 2014 1:49 am

"wicks" is akin to soak up or absorb or draw off (liquid) by capillary action.

bigbadjohn · Post by **bigbadjohn** » Fri Oct 10, 2014 7:29 am

Petroleum will move through teflon tape like a hot knife through butter. Hang strip of teflon over a container so it just touches fuel, inside an hour 4 or 5 inches of the tape will be fuel soaked.

The install instructions for most fueling components specifically say not to seal them with teflon tape

justinforman · Post by **justinforman** » Fri Oct 10, 2014 12:27 pm

Loctite pipe joint compound. Works great, but is a pain to take apart.

Post by **Kperlow** » Sun Oct 12, 2014 11:40 am

Gasoila with teflon.

Post by **tankgenie** » Mon Oct 13, 2014 2:06 am

Which gasoila Kperlow? http://www.gasoila.com/products/pipe-th ... ants.html/

We had been using the PLS 2 on the diesel lines, but that wasn't working well on there on. Another contractor we work with swears by the E-seal on diesel. And a third says regular pipe dope plus Teflon, whatever that is.

bigbadjohn · Post by **bigbadjohn** » Mon Oct 13, 2014 2:32 am

PTFE is the generic name for Teflon. Teflon is a Dupont trademark. PTFE in the pipe dope adds lubrication and makes it a whole lot easier to get all your fittings 1/4 turn tighter. PTFE/Teflon doesn't conduct fuel, it's actually the binder in the tape material that conducts the fuel. There are petroleum approved tapes, but they aren't the ones you buy for 79 cents a roll at the local home improvement warehouse.

Hard set sealants make a better seal but they tend to crack and leak if there's any movement along the pipe so not recommended unless you are sealing the pipe under cover where no one can walk on it and are clamping it to structure every few feet.

There are manufacturers that suggest sealing threads with both PTFE tape and pipe dope. The tape definitely helps seal the threads but it can make your fittings seep if you don't use a petroleum approved brand of tape. It helps to read the directions too, depending on the brand/thickness of tape it usually calls for somewhere between 2 and 5 wraps of the fitting, I see a whole lot of guys who put 2 or 3 times that amount on the threads and wind up pulling all the tape out of the threads into a big ball of tape inside their fitting.

Post by **tankgenie** » Mon Oct 13, 2014 4:48 am

Thanks. Just trying to figure out what iteration of the gasoila to use. PLS-2 or E-seal or Hard-set with diesel/ULSD?