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Tcraftdriver
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I am sharing my experience only for reference. I am not suggesting you do the same. I accept no responsibility if you do what I did and it damages your vinyl. I only share this experience for your knowledge on what worked for me. It might not work for you and has the potential to irreparably damage your interior. What I did, I did out of desperation and with the knowledge that I fully intend to replace my car's interior, so if I was to damage the existing VINYL interior it would not cause me great anguish and beating of my chest.
Some months back I purchased a 1959 TR3a with a white interior. The seats are in decent condition, the rest is rustic to fair to good. Carpet is not part of this. The all white interior had a lot of black marks like you see from carrying dirty, greasy, parts around behind the seats. Some marks looked like ball point pen marks. Others were oil based smudges, ground-in dirt and different colored stains on all the panels including lots of black marks on the seat backs and side panels behind the seats.
I started with Turtle Wax Vinyl Cleaner and Turtle's Cleaner Wax followed with 409 spray cleaner, Fantastic spray cleaner, Windex, Armorol, Mother's Tire Cleaner, saddle soap, Lemon Pledge, Alcohol, and Fast Orange Hand Cleaner with Pumice. Only this last one had any effect but took so much scrubbing I was concerned about wearing away the "grain" in the vinyl surface. Frustrated, I tried Mineral Spirits (Paint Thinner) which did remove some of the smudges but nothing worked on all the black pencil like marks, stains, and/or ground-in dirt.
I took the final plunge and pulled out the gallon can of Lacquer Thinner. Crazy, yes, but nothing else worked and a new interior is in the future so using a white terry cloth towel cut into 12" squares, folded over, and pretty well wet down with Lacquer Thinner, not dripping, but wet, I got busy. I did this outside with the top and side curtains off and the carpet out of the car. I wore gloves.
HOLY MOLY - did this work! With light rubbing the black marks, smudges, oily spots, stains, and all manner of ground-in dirt just plain disappeared. The vinyl surface did become very slightly tacky to the touch until the Lacquer Thinner was completely dried and then that went away. I never lost any of the "grain" that was/is part of the vinyl surface. I was careful not to spend too much time on the same spot. As it became clean it also brightened so I had to wash all the vinyl to make it all look the same. I found that I had to very frequently turn the cloth to a clean surface and went through about 10 cleaning rags. Some small amount of vinyl appeared to be accumulating on the cleaning rags, just enough to turn the white rags to a kind of off white color but not enough you could scrape it away, just enough to discolor the towel. This told me it was time for a new towel. The end result is that the interior almost looks new. I cannot believe how nice it looks. All the black marks, oily spots, smudges, stains and even ground in dirt, is gone. I was careful to avoid working threaded seams more than a quick wipe so as not to dissolve the thread that held things together. The interior still looks like it has a few miles on it but now it is sparkling clean, white all over and decently presentable.
As above, I do not recommend you do the same. Lacquer Thinner is a very, very, powerful solvent. Your vinyl might not stand up to the Lacquer Thinner like mine did. You could dissolve the threads that hold seams together. You could suffer irreparable harm to your vinyl, so, if you do decide to try what I did, BE VERY CAREFUL and find a small out of the way spot and experiment there. Be sure to use a white terry cloth towel and as soon as you see any deposits on it, use a fresh towel surface. Test the vinyl surface for tackiness. If it is becoming tacky, stop cleaning that area and give it time to fully dry. I am sure that some of the discoloration I saw on my towel samples is a small amount of surface vinyl dissolving off into the towel along with the dirt it carried but I cannot see any damage to the vinyl anywhere. It just looks clean and decently presentable. Do not smoke and work outside. Lacquer Thinner fumes can be toxic.
Some months back I purchased a 1959 TR3a with a white interior. The seats are in decent condition, the rest is rustic to fair to good. Carpet is not part of this. The all white interior had a lot of black marks like you see from carrying dirty, greasy, parts around behind the seats. Some marks looked like ball point pen marks. Others were oil based smudges, ground-in dirt and different colored stains on all the panels including lots of black marks on the seat backs and side panels behind the seats.
I started with Turtle Wax Vinyl Cleaner and Turtle's Cleaner Wax followed with 409 spray cleaner, Fantastic spray cleaner, Windex, Armorol, Mother's Tire Cleaner, saddle soap, Lemon Pledge, Alcohol, and Fast Orange Hand Cleaner with Pumice. Only this last one had any effect but took so much scrubbing I was concerned about wearing away the "grain" in the vinyl surface. Frustrated, I tried Mineral Spirits (Paint Thinner) which did remove some of the smudges but nothing worked on all the black pencil like marks, stains, and/or ground-in dirt.
I took the final plunge and pulled out the gallon can of Lacquer Thinner. Crazy, yes, but nothing else worked and a new interior is in the future so using a white terry cloth towel cut into 12" squares, folded over, and pretty well wet down with Lacquer Thinner, not dripping, but wet, I got busy. I did this outside with the top and side curtains off and the carpet out of the car. I wore gloves.
HOLY MOLY - did this work! With light rubbing the black marks, smudges, oily spots, stains, and all manner of ground-in dirt just plain disappeared. The vinyl surface did become very slightly tacky to the touch until the Lacquer Thinner was completely dried and then that went away. I never lost any of the "grain" that was/is part of the vinyl surface. I was careful not to spend too much time on the same spot. As it became clean it also brightened so I had to wash all the vinyl to make it all look the same. I found that I had to very frequently turn the cloth to a clean surface and went through about 10 cleaning rags. Some small amount of vinyl appeared to be accumulating on the cleaning rags, just enough to turn the white rags to a kind of off white color but not enough you could scrape it away, just enough to discolor the towel. This told me it was time for a new towel. The end result is that the interior almost looks new. I cannot believe how nice it looks. All the black marks, oily spots, smudges, stains and even ground in dirt, is gone. I was careful to avoid working threaded seams more than a quick wipe so as not to dissolve the thread that held things together. The interior still looks like it has a few miles on it but now it is sparkling clean, white all over and decently presentable.
As above, I do not recommend you do the same. Lacquer Thinner is a very, very, powerful solvent. Your vinyl might not stand up to the Lacquer Thinner like mine did. You could dissolve the threads that hold seams together. You could suffer irreparable harm to your vinyl, so, if you do decide to try what I did, BE VERY CAREFUL and find a small out of the way spot and experiment there. Be sure to use a white terry cloth towel and as soon as you see any deposits on it, use a fresh towel surface. Test the vinyl surface for tackiness. If it is becoming tacky, stop cleaning that area and give it time to fully dry. I am sure that some of the discoloration I saw on my towel samples is a small amount of surface vinyl dissolving off into the towel along with the dirt it carried but I cannot see any damage to the vinyl anywhere. It just looks clean and decently presentable. Do not smoke and work outside. Lacquer Thinner fumes can be toxic.
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