Can I use any sealant for the leakage in proportional valve in my 2002 Hyundai Elantra?

retorque the fittings snugly with a line wrench, that's all it needs....barring a physical crack.

looks like a washer under the main fitting? assure this one is sound and has no scratches that fluid can creep thru, better still replace that bugger with a brand-new one...have yet to meet a substance would stand up to brake fluid, as a matter of fact are artists use it as a paint remover to clean brushes and palettes~humph like J-B weld is what you're thinking, despite all claims on the outside of the box, this stuff ain't all that! just do it properly with new sealing parts!

Agreed sealant wont work on brake lines pressure is too high plus i wouldnt skimp on brake parts. extreamlyimportant part and needs to be addressed asap.

According to the box, like the Judge so accurately states, the manufacturers of JB Weld will tell you it will hold the blades on an airplane prop to the hub.. "bolts? ...we doan need no stinkin' bolts" but the stuff is crapola. My point is vote #3 with those guys, kbro and The Judge, matter of fact a new master cylinder would feel real nice with your kids in the car, eh? I think Rub o' the Brush has brake fluid in it

rub o' the brush---everyone I know has had a wapatewie party in which a local galvanized trash can is emptied out, filled with bags of ice, eveyone brings a bottle of something and every guest contributes a bottle, stir with a shovel...and serve to thirty guests...in my case was a X-con science fiction convention in 1982...'scanners' was the featured film....it was challenging to contain my beverages under those circumstances, but an experience we shall never forget~

Is there a universal proportional valve? All cars have them and I've never had to replace one. The issue here seems to be the replacement cost. Could one from another car work? Could it be a junk yard/eBay item?