Both filler hoses on my 1990 3.9 Plus 8 are cracked and leak badly when re-fuelling. This could be due to age (or Ethanol deterioration?). The filler caps are lockable, lozenge-shaped and chromium-plated .
I had a UK 1990 Plus 8! (made earlier in that year) A 1990 3.9 is a collector's item!
I loved mine and miss it! Best touring car I had in my Morgan collection..in fact the best touring car I have had of any
marque. It would make friends for us.I put a 4.6 in it. I replaced ALL rubber when we bought and restored it in 2004.
Rubber ages, dries out and rots. It must be regularly replaced before sadness strikes. Modern materials are much
smarter. That being said, I always used the MMC ones. Though they were/are new.
I have bought some new 51mm rubber hose from
Hose Supplier. This hose is reinforced with a spiral spring bound into the hose construction..
But those hoses are a REAL pain to fit, even worse than the MMC hoses. Morgan never angled the tank entries as they
should. If you do not want a struggle, even for those of us who have done it many times, you must buy flexible fuller hose.
here additional wisdom in that as the MMC filler hoses or rigid ones detach completely with a rear or rear side impact.
Don't ask me how I know?

The consequences of stiff hoses are not fun.
At this stage I would really appreciate advice from someone older and wiser:
1. How can a new stiff fuel filler hose be installed with the fuel tank and filler necks remaining in place?
2. If the filler necks should be removed first, how is this achieved?
I doubt super stiff hoses CAN BE installed.
And why risk shearing the tank inlets? But removing the filler assemblies is
not difficult. There are rubber washers (if they are still there) and
a threaded ring on the interior side of the fillers. Diagram
below. Forgive me the diagram is from a later 4/4 which is not identical to what you have but shows you how these assemblies
work.
If you want a source for proper cuttable, shapable fuel hoses, I am sure we can find something nearby. They are all the rage.
L.
P.S. BTW, do you want to remove the need of using filler keys?
![[Linked Image]](http://www.gomog.com/TEMP/FuelFillerAssembly.jpg)