Originally Posted by Alec300SD

I think 8mm i.d. hose is the original MB specification, but metric diesel fuel hose hard to source locally in most areas.

The rubber fuel supply hoses only see low fuel pressure, so 5/16 works okay if you snug the hose clamps adequately.

Parker 5/16 Super-Flex FL Series 397 hose is an excellent barrier fuel hose (compatible with biodiesel) that I use on my MB diesels.



Change your primary (plastic) and secondary (metal) fuel filters before doing the diesel purge.

Sicnce you have an '01' fuel filter head (615 092 01 08) you may need a new aluminum crush washer and also an o-ring for the hollow bolt when you change out the secondary fuel filter.



I upgraded my W116s to the '02' fuel filter head when I did the CAT 1-7050 fuel filter upgrade.

http://www.peachparts.com/shopforum/diesel-discussion/386946-fuel-filter-upgrade.html



If anyone needs a kit, they are still available. Just send me a PM.

http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/386988-fs-cat-1r-7050-fuel-filter-upgrade-kits-om61x.html