Flared tubing connections - Really this is the best technology
 

I don't normally rant on here but I have to relieve some steam after a tough weekend!

I bought a set of used 280 k-planes this winter for my scarab, they came with pumps lines and the planes. The through hull fittings were broken so I had to replace them but everything else looked in decent condition other then a little cleaning required!

So I get the tabs all mounted, get the pumps mounted, all the stainless lines run, wire the pumps fill them with ATF and fire them up! Well guess what, every friggen union leaks except where the lines attach to the new through hull fittings on both the inside and outside. So basically the lines leak at the pumps and the pistons on both pressure sides!

With ATF running everywhere I start to snug all the leaking connections and try again, no better. One connection at the pump doesn't just drip but literally streams out of the fitting when the pressure comes up!

Now I am totally aggravated and break the whole system down and begin to inspect the flares and the mating surfaces, the flares are all fine as they are double flares in stainless. The mating surfaces on the other hand have a visible bur where it looks like the line made an impression on the soft brass!

I ordered some conical washers to hopefully remedy the issue but if not I am not sure what I am going to do!! I just can't believe that for the money they get for these kits that they don't have a better design for these high pressure connections or at a minimum fix the issue with tightening a stainless flare against a soft brass surface!

Then to top the whole weekend off I found out that my steel trailer under my 21' Tahiti jet boat is rotting from the inside out so there goes another $3000 in a new trailer! WTF!! :angry-smiley-038:

Sorry for the rant!!

Since these parts were previously used, the flares could have been damaged. I would get my double flare tool and try to reform/ true the flares. Stainless has a history of being difficult to seal with flares, even against steel seats so your planes manufacturer used the brass seats. Can you replace the brass seats? Once the flares are trued and with new brass seats, you should be OK.

I have thoroughly checked the stainless flares and even measured the angles and the flares are fine, like I said the brass is visually burred, not sure there is a way to replace the brass inserts in the rams and no way I am buying new rams at $1500

I am hoping the brass conicle washers I bought fix the issue!

Just frustrated with what seems like such a ****ty way to create a reliable sealing surface!

Make sure the angles on the tubing is the same as the fittings. Some Stainless tubing is flared @37* and brass is usually 45*
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fixx
 

i have ran into this before,,what i have found is when the line is almost snug i twist the line about 1/4 turn counter clockwise then snug the line..when making the final 1/4 turn i twist the line with the with the fitting and this will usually scor the ss line into the brass fitting so it wont leak.