There is a product called Marine Strip by a company named Restoration Technology. I don't know if it will work on your coaming pads or not but it's pretty amazing stuff. We use it on our trawler for cleaning fenders, power cords, etc. we clean with it and then treat with 303 Protectant. Looks like new. In Fl we can buy it several places, Boat Owners Warehouse having the best price I've seen. But in Maine, No Joy! I had to order a quart from the mfgr. The shipping was almost as much as the purchase (not really, but I'm spoiled by Amazon Prime!). Look on Restoration Technology's website to see if there is a source near you.