The Billet VW/Audi Upper Radiator 4Y Pipe replaces the junk plastic pieces found in OEM upper radiator hose P/N 1J0-122-101AP (1J0122101AP), 1J0-122-101CG (1J0122101CG) and 1J0-121-087J (1J0121087J). (MK4 VR6 12V)
This part can also be spec'd without the lower auxiliary radiator feed nipple for those wanting to delete the often problematic auxiliary radiator and all of its associated plumbing! The aux rad delete option includes a straight billet aluminum auxiliary radiator return hose delete pipe which replaces the plastic tee in lower radiator hose P/N 1J0-122-051R(1J0122051R). This option also deletes the short adapter hose located under the 4Y which connects to the aux radiator return, P/N 1J0-122-101AR (1J0122101AR). Please note the auxiliary radiator delete option is intended for manual transmission vehicles only.
The flimsy plastic OEM upper radiator hose 4Y junction located in the upper radiator hose quickly 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. Likewise, the auxiliary radiator and its associated hoses and fittings clutter up the engine bay and are also prone to leaks which can cause catastrophic failure to the engine due to overheating.
Our billet upper radiator hose 4Y and the auxiliary radiator delete pipes are made on one of our state of the art CNC machining centers 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 deltion 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 MKIV 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).
MKIV R32 with upper radiator hose 1J0-122-101CG (1J0122101CG)
