M38 Fuel shut-off valve brass connector at McMaster-Carr

timber21 · Post by **timber21** » Sat Feb 09, 2019 11:29 am

Had a small leak at the fuel shut off valve caused by a hairline crack on the brass connector. Could not find it locally but located an almost identical part from McMaster-Carr, it is a typical automotive 45 degree flared fitting 1/4" tube X 1/8 NPTF, Part Number 6432T117, $4.95 plus SHI. The only difference I found, the new connector is slightly flared where the face of the threaded portion of the valve touches as opposed to the original that is flush.

Post by **wesk** » Sat Feb 09, 2019 1:25 pm

6432T117 is for a regular external flare tube. You want a fitting Ordnance PN 191573 (Ord Stk # H106-0191573) for a 1/8" female P to 1/4" inverted flare tube.

timber21 · Post by **timber21** » Sat Feb 09, 2019 3:06 pm

Indeed, but could not find one, and the connector from McMaster does the job.

4x4M38 · Post by **4x4M38** » Sat Feb 09, 2019 4:24 pm

Understand that a regular flare fitting may do the job, but that an inverted flare end on the tube may resemble a regular flared end, but is done with a different tool.

The end of the tube is not flared outwards, but is flared inwards.
There is a specific set of dies used for the inverted flare.

4x4M38 · Post by **4x4M38** » Sat Feb 09, 2019 4:52 pm

Inverted flare fittings have been used for decades on brake lines.
They can be found at auto parts stores but usually one has to go in back
and dig through the fitting boxes because the millenial up front can’t find it on the computer.

Fastenal also carries inverted flare fittings.

Post by **wesk** » Sat Feb 09, 2019 5:00 pm

Once you tighten that new External 45 Deg. flare fitting you will have permanently deformed the inverted flare. You have been lucky and your mix and match has not leaked.

My advice to the rest of our members is to Not Mix & Match fitting and tubing types. If one looks hard enough one can find the correct part making his repair less risky.