I know the topic has been around before, but I couldn’t find anything that would help me. Yesterday I found two nasty bird droppings on my canvas roof. Some people suggested hoovering, but this was kind of a solid gunk, embedded in the fabric and hoover didn’t work.
I soaked a piece of kitchen towel in car shampoo (Autoglym) solution and put it on top of each dropping for a few minutes to soften it. Then, I started gently dabbing it with the towel and gradually managed to remove most of the gunk. I kept dubbing with fresh kitchen towels soaked with car shampoo until it was all gone. It looked more or less OK.
However, when it dried, there were two very visible stains, as in pictures below. How do I remove this stuff? I waterproofed the roof about a couple of months ago and avoided shampooing it since.
Hoover doesn’t help, these are now stains in the fabric. I can soak them with water (as I did with shampoo solution), but after drying the stains are there. After yesterday I haven’t tried washing them again.
Raymond at JST (Jack Smith Trimmers) in Swansea advocates diluted Fairy Liquid and hot water followed by gentle use of a nail-brush in the direction of the weave as the best way to clean a dirty vinyl backed canvas (or mohair as we still call it) roof, plenty of rinsing with a hose afterwards.
Advice from the Autogylm site. Use the shampoo leave it wet and cover with something like clingfilm overnight to keep the area wet and the cleaner will continue to work. No experience of this myself but perhaps worth a try.
I had a go at these stains last weekend. First of all, gently brushing with Fairy Liquid doesn’t help. The stains seemed to be embedded too deeply in the fabric for this.
So, I covered them with kitchen towels soaked with diluted car shampoo and left for several hours in the garage. Did not cover with cling film, but they were kept moisture for a while. Then, I washed the roof with pressure washer, using a lot of water. After it dried, one of the stains (the bottom picture) disappeared, and as for the top one, the fabric had a slightly different shade, and the shade size corresponded not to the original stain, but to the treated area. Perhaps, it was the effect of me dabbing it furiously with the kitchen towel in the first place.
I was intending to hover this shade, but it rained heavily the next day and my car was parked outside (normally it is in the garage). The roof was covered in water, and you could clearly see where I treated the stains (photo below). I guess I will have to treat these spots with waterproofing stuff again. Anyway, the car has dried now and the stains disappeared completely. Bird poo on the fabric roof is a nightmare. It doesn’t happen to me too often, as my car is parked overnight in a garage. After recent experiences I park it in a garaged space at work as well.
By the way: does anyone know why font size is changing in my previous post? I haven’t touched fonts, it was just plain text, and a couple of sentences are in larger font. I even tried editing and setting the same font everywhere, but it doesn’t help.
Strange, I can see you’re suffering but we’ve got the same roof and don’t have a problem. Nor with our previous Saab with blue canvas top parked outside for 4 years. All I’ve ever done (goes right back to my 70’s vinyl roofs too) is treat the roof like the rest of the car. Hose (or pressure washer at a sensible distance) it off before starting, wash with a sponge and car shampoo (always used Turtle, Nano at the moment) then hose off and leather (not the roof). If I were to suggest anything it would be never clean it dry, or with a brush, or with dishwashing liquid which contains salt and heaven knows what else. Soak it and let it come off with plenty of water and car shampoo.
This is exactly what I did before. I had some bird droppings on the roof, so just washed the entire car with pressure washer (gently), car shampoo, lambswool mitt and plenty of water. Then, I read people saying you should never wash your roof with shampoo, but hoover instead. Shampooing removes waterproofing agent, they say (I did treat it with Gtechniq I1 a couple of months ago). So, the next time I got bird poo, I tried local treatment, as described above. Either this particular bird muck was particularly bad, or local treatment doesn't work.
The problem is I don't wash the car every weekend. It is garaged for most of the time and I use it occasionally, so it doesn't need frequent wash. If a bird happens to relieve itself on my roof when the car is clean, I don't really want to get all the washing equipment out (pressure washer, hose, buckets, mitt...). I hoped there might be a simple local treatment to remedy one dropping spot.
Ah well now you know you were right. Yes if it’s just been freshly bombed try a couple of buckets of water and a sponge but if it doesn’t come straight off get the hose out.
Halfords do a small box of sachets a bit like wet wipes that are designed to get rid of bird droppings. They do work on bodywork amazingly quickly but I do not know what lasting effects they will have on soft tops.
Old “double duck” roofs were
2 sheets of cotton canvas (duck) with a water proof rubber membrane
in between. They were heavy, faded and rotted, and went mildew. There may have
been some benefit applying dressings.
New “mohair” roofs (80’s
onwards) are similar double duck construction with a waterproof
inter-layer but are made of acrylic yarn (not cotton or Angora goat,
they perhaps get the name from the slight shine of the fabric).
These modern hoods are very colour fast
and UV stable. They are essentially plastic and don’t need dressings
or to bead-up water to be waterproof and it may even seal the muck in
and make them harder to wash.
Interesting article in the Telegraph today on this subject. Really about damage to paintwork but could apply to soft tops. It stated that Autoglym have discovered that the reason for discolouration of paintwork is not, as previously thought, due to the acid or alkali in the droppings but to the difference in temperature of the surface under the dropping and adjacent to it. Particularly in bright sunlight. It went on to say that some bodyshops can remove the stains using heat treatment, but the results can be variable. Perhaps worth further investigation! Any experience of this anyone?
