DIY Replacement for Part number 16 12 1 233 517 ( plastic or aluminum nipple), listed as NA from BMW.
Available from most hardware store plumbing fittings departments are brass ‘barbed’ hose connectors. You will need two in the appropriate size (diameter/length) to replace the original plastic nipple in your fuel taps. Take an old one with you to the store to compare. Cut one end off leaving one end with the full flange. Wrap the flange with several loops of Teflon tape and install with a new gasket. This is a permanent replacement. Your factory cloth covered rubber fuel line will not care that the fitting has an RCH larger OD than the metric original plastic job. The ID is correspondingly larger too. The finished part pictured has been in use for 30+ years.
Available from most hardware store plumbing fittings departments are brass ‘barbed’ hose connectors. You will need two in the appropriate size (diameter/length) to replace the original plastic nipple in your fuel taps. Take an old one with you to the store to compare. Cut one end off leaving one end with the full flange. Wrap the flange with several loops of Teflon tape and install with a new gasket. This is a permanent replacement. Your factory cloth covered rubber fuel line will not care that the fitting has an RCH larger OD than the metric original plastic job. The ID is correspondingly larger too. The finished part pictured has been in use for 30+ years.