Cleaning white plastic lettering on dodgers?

[Oldgeezer]

Any ideas?
They are yellowed as not been used / cleaned for a few years.
I've tried Cif and coarse sponge - it might work eventually but so far results not very good

Options
1. Keep scrubbing for some days..... weeks.......
2. New letters and sew them on - (too much work!)
3. New dodgers - £200+ (am I being tight or eco conscious?)
4. Leave them, as you cant tell from the shore that they aren't white

Any other options please....

 

[Clancy Moped]

Bleach?

 

[Major_Clanger]

Oxalic acid is your friend........

 

[Concerto]

Cover with white self adhesive vinyl (buy sign makers vinyl from eBay) . Then carefully trim round with a sharp knife (snap off blade type).

 

[Oldgeezer]

Many thanks - Bleach and barkeeper friend tried - and failed
now I'll get some sticky vinyl!

 

[Bob@SYH]

It might be worth trying Wonder Wipes, Big Wipes or a similar decorators hand wipe, these usually contain a concentrated detergent and get all manner of stuff off other stuff. I suggest them following an accidental but rather fortuitous encounter with them on the vinyl tubes of an old and very dirty RIB I had, I had left one on the side of the boat and discovered that with a little light rubbing it removed all the ingrained grime really easily (you know the sort of sticky greasy grime that they get like after years of neglect)... ended up doing the whole boat with them.
Alternatively there are proprietary cleaners for fenders etc like Anchor Marine's Fender Cleaner which may well be worth a try if you don't fancy cutting out letters.

 

[johnalison]

The name in reflective tape would be rather fetching I think.

 

[PeterBoater]

Any ideas?
They are yellowed as not been used / cleaned for a few years.
I've tried Cif and coarse sponge - it might work eventually but so far results not very good

Options
1. Keep scrubbing for some days..... weeks.......
2. New letters and sew them on - (too much work!)
3. New dodgers - £200+ (am I being tight or eco conscious?)
4. Leave them, as you cant tell from the shore that they aren't white

Any other options please....

Everbuild PVCu Solvent Based Cleaner, from Toolstation or the internet; also good for fenders. Can be used with magic eraser sponges. I found it best to wash it off with the yellow bath cleaning stuff, rather than wipe with a dry cloth as per the instructions. NB the caution on the bottle about marine life.

 

[peteK]

I used oxa lic acid with good results.