Replace the MK4 12v VR6's notorious junk plastic Radiator 4Y Pipe found in OEM upper radiator hose P/N 1J0-122-101AP (1J0122101AP), 1J0-122-101CG (1J0122101CG) and 1J0-121-087J (1J0121087J).
This flimsy junction dries out and becomes super brittle. If you look at it wrong, it will snap and leave you stranded. Or worse, turn your high dollar VR6 motor into an overheated paperweight.
Our billet upper radiator hose 4Y and auxiliary radiator delete pipes are both made from aircraft-grade 6061-T651 aluminum. The 4Y is professionally TIG welded and both parts are leak tested. You could drive your car over these, but we'd recommend doing that to the OEM plastic versions and installing ours instead!
A 1/8 NPT fitting is used for the radiator reservoir return line. So, if main coolant reservoir deletion is desired, 1/8 NPT threaded plug may be swapped in its place. A coolant temp sender can also be installed there for aftermarket sensor applications.
Applications:All Mk4 Golf/Jetta VR6 12V engines (with upper radiator hose P/N 1J0-122-101AP (1J0122101AP) and 1J0-121-087J (1J0121087J) and lower radiator hose 1J0-122-051R (1J0122051R).
Mk4 R32 with upper radiator hose 1J0-122-101CG (1J0122101CG)