I was a Sign Painter for over 20 years in SW
Florida, and specialiZed in lettering boat in and out of the
water.
This is based on my working experience dealing with hundreds of boats.
1. Vinyl lettering should only require a good blow dryer. Generally heat a
single letter, and then start at one corner, and pull the letter back on itself slowly while still applying the heat. Best guide for how hoy is simple. If it is too hot for your fingers it is too hot. It will be a little uncomfortable though. Very old vinyl will be harder and more brittle which means coming off in smaller pieces. There will almost always be a little residue left which can be removed with acetone, or "goo-be-gone".
THE GHOST IMAGE....there will be a ghost image where the letters were. This is due to UV breakdown of the exposed area, and the gel coat under the letters will be shiny and actually a little raised, as the other areas have been deteriorated just a little. Most often a little ONE THOUSAND GRIT WET OR DRY sand paper, and then some rubbing compound will eliminate the ghost image.
CAUTION...because the gelcoat often yellows just a bit, the area under the letters as well as the sanded and rubbed out area will now be whiter than the surrounding areas. Plan on very lightlly
sanding and buffing the whole transom.
DO NOT WAX the area before applying the new vinyl name.
2.The "oven cleaner" method is for removing hand painted lettering ONLY.
The best I have found is Easy Off, and it must be the kind that does NOT require the oven to be heated. Do it on a warm day, preferably when the sun is falling on the transom. This applies to both paint and vinyl.
Two shorter applications of the oven cleaner are better than one longer one. Be careful as this method softens the gelcoat just a little and makes it easy to scratch. It re hardens afterwards. USE RUBBER GLOVES AND
SAFETY GLASSES AS OVEN CLEANER IS VERY CAUSTIC. Have a water hose ready to rinse it off your skin or eyes. You will also need the water to rinse the cleaner off the
hull and stop the
cleaning action.
3. This applies to white gelcoat only. Painted hulls, are much more iffy because you have to take into consideration the condition of the base color.
SOOOOO heat the VINYL, peel it off, try to rub out the ghost image first, and if needed use 1000, or even 2000 grit wet or dry.
ONE OTHER WORD OF CAUTION.
When ordering vinyl lettering for your boat or anything else outside make sure you are getting "PREMIUM/HIGH PERFORMANCE VINYL" Many of the "deals" are because they are passing of low grade or intermediate grage vinyl. If you try to save a few bucks you will hate yourself later as the graphics will not last.
Feel free to PM me with any other questions.
This will take an afternoon, and probably a six pack, but it is doable.