What cleaner will remove tree sap from your boat cover material?

This was a question from Doug in Texas.
Doug had a sunbrella boat cover covered with tree sap.
The following post was his experiment with removing it and it was important enough to share with you.
He had some really good information.


Update: I snuck away from what I was supposed to be doing yesterday.
I tried several test areas with different things.
Bugs B Gone failed. I could have let it set longer but I don’t want anything to harm the adhesive between the polyester and the backing.

Chemical Guys Nonsense cleaner failed 

Simple green pro hd,the purple seemed too aggressive.

303 Marine Multi Surface cleaner was the winner. It did the best and is safe on all marine fabrics according to 304 and the company I purchased the cover from (which they sell 303)however they said it would be better for the fabric to mix white vinegar , Borax powder and warm water in a spray bottle. 
So my wife is picking me up some Borax and I’ll at least give it a try.

For all cleaners I used one of my soft hose hair detailing brushes I use for my truck. It’s only 1” diameter and worked perfectly for testing small areas. When I saw the 303 working though I did a strip about a foot wide down one side of the cover making several passes with the brush. It removed most of the sap but left it where it must be deeper in bedded in the fabric. I figured another pass should get it. It also has trouble with some small spots that are really dark but I don’t mind elbow grease. I’m thinking of using a larger soft brush like a shoe polish brush to do the complete cleaning along with my extraction machine. I used to clean carpet and upholstery and know several tricks with the machine also it’ll keep from leaving any residue so I can retreat the cover. You can see the clean spot in the pictures. I can actually see khaki yay. It wasn’t finished drying when I took the pictures but I can really see the difference today.

Update 2
Oh I also have a little two man boat made of poly instead of fiberglass and it got hit bad. While walking past it last night I hadn’t rinsed the 303 out of my brush yet so scrubbed an area and it made the boat look brand new. After years of aging and being out in the elements. I haven’t used it in three years and need to get rid of it. Now I know what I’m going to clean it up with first.

Thanks Doug, good information !

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