TOPIC:

Here are a few pictures of the seat at the front of it there is primer the previous owner primer the gas tank with the seat on the other marks are an unknown substance wondering how to clean the seat. Thank you

Try dishsoap mixed in warm water and see what happens.  I'm sure there is a stronger solvent that would work but may do damage to the seat cover.  Simpe Green is also an option

I tried the dish soap and water with no results. I will try the simple green next thank you very much

I would try baby oil first to soften the vinal then wash with dish soap and water. Don't use Armor All. It will dry out the vinal and cause cracking. 
Steve

I have never tried to remove paint from vinyl so do not have any suggestion that has been tried. I have at times made use of different products for cleaning it with good results but not sure what to suggest for paint. They removed dirt/oil/mildew ect but not sure they will touch paint? A quick online search will fill pages of vinyl cleaners and how-tos

Something strong enough to pull the paint with out damage to the cover.  How important is the cover to you?  Can you find and afford or make a new cover? I guess if I was in your shoes I would take the old cover off and attempt to clean it with  some type of oil based cleaner. If that does not work maybe some rubbing alcohol and see what it does. 

I hate to say this... but Toluene  is recommended for paint removal. The however attached: this is a petroleum product and will probably either degrade or discolor the existing seat cover. If you get some, use it on a clean rag, in a hidden area to see what it's gonna do to the cover. This is a very refined product that is used by painters, who use oil based paints, to clean brushes and thin the paint.

edit: I bought my gallon, 10 years ago, from Sherwin Williams for ~$25. A little goes a long way and it's considered very toxic.

 

I would try Mary Kay oil-free eye makeup remover or WD40.

I would use non-clorinated brake cleaner on a clean rag. It won't hurt anything but should take off the primer, try it several times in a row.