Need help with this one …on the electric hard top I have some paint bubbling up on the part where the break light is. Been told this is a fault on the mk3
I’d be interested too as I have exactly the same on that deck but near where the hard top actually starts. Was going to start looking at it today but not with any plan yet. I have a couple where I can see primer or the polycarbonate now. Mine’s Galaxy Grey for reference.
My skill set is novice when it comes to paint.
Been told this is a fault from manufacturing.
Mine looks like this on the rear deck along the of the rear screen. Each blister is about 2-3mm across. The rest of the car is fine.
I’ll probably have a go with Chipex just to make is a bit tidier but then, when money’s available, it’ll be a trip to get at least the rear deck repainted.
Has it lifted the paint also ?
Yes, the white dots are where the paint has lifted and there are a few places where the clearcoat seems to be lifting plus a few bubbles which are the first stage I guess.
The white is either the primer or could even be the polycarbonate itself?
Of course, in this position it gets the full heat of the sun but something must be under there to bubble or it’s a reaction of some kind.
I think the previous owner had a half cover on it as the rest of the roof has some minor tell-tale milky appearance in some light or when wet. Another item on the agenda.
The blistering is caused by water vapour trapped in the composite deck panel. It freezes in very cold weather, ice crystals form, and they blow the paint. A respray won’t cure the problem unless you drive out the water vapour, which usually entails rubbing down the deck and then baking it slowly first. That requires the deck panel to be removed which is quite a complicated procedure.
I noticed this issue on my rear deck earlier today. If it’s a common fault with the Mk3, you would think Mazda would do something about it, but highly unlikely they would even admit there is a fault.