Rear Bumper - Trapped Dirt = Corrosion?

[makeshiftUK]

I noticed a few weeks back that there appeared to be some bubbling on my rear bumper, just under what I can only refer to as a boot-lid slam cover... I thought the bumper was plastic! My untrained eye is pointing towards said slam cover lifting/distorting from what appears to be trapped dirt underneath. With the slam cover lifting, I think it's also scratching the boot lid itself... and subsequently spotted a bit of corrosion on the edge. The pictures below should better explain my story.

As a temporary measure till I get it fixed, is there any downside to removing the slam cover and cleaning underneath it? Is it just glued in or are there retaining clips of some description?

 

[Silvercat]

I think the boot lid is aluminium ( as per the bonnet) so there shouldnt be any corrosion. But you can get "corrosion' of sorts on the aluminium when the paint has been contaminated with steel fillings during manufacturing which can be a problem. I had this on my bonnet on the underside, on my 2009 QP.

 

[Gp79]

Aluminium doesn’t rust but it still oxidises, just look at old land rovers / range rovers. It forms a white powder as it disappears.
The range rovers were bad where the aluminium met steel and the insulation material between the two different metals broke down over time so formed a nice corrosion cell ☹️

 

[Gazcw]

That slam cover as you call it looks very wibbly wobbly. Is that a flat spot on the bumper you or just reflection?

 

[makeshiftUK]

That slam cover as you call it looks very wibbly wobbly. Is that a flat spot on the bumper you or just reflection?

I've taken another snap below to capture the 'bubbling' - I'm not sure which area you're referring to, but I don't think I've got any flat spots.

Open to recommendations of bodyshops in Surrey...

 

[allandwf]

That looks like aluminium corrosion to me, if paint chips off it will be white and powdery under it. It is where moisture has somehow managed to get under the paint, a stone chip is enough to let it in.

 

[Gazcw]

I've taken another snap below to capture the 'bubbling' - I'm not sure which area you're referring to, but I don't think I've got any flat spots.

Open to recommendations of bodyshops in Surrey...

 

[makeshiftUK]

Very weird reflection of my porch door!

That looks like aluminium corrosion to me, if paint chips off it will be white and powdery under it. It is where moisture has somehow managed to get under the paint, a stone chip is enough to let it in.

Thanks, if society ever returns to normal this will be a priority job.

For the record, a quick google of the 'slam cover' suggests that it sticks down and comes with an adhesive strip.

 

[allandwf]

Very weird reflection of my porch door!


Thanks, if society ever returns to normal this will be a priority job.

For the record, a quick google of the 'slam cover' suggests that it sticks down and comes with an adhesive strip.

I was referring to the bootlid, is there not a patch on it on the rhs bottom edge? Hopefully my bad and just a reflection.

 

[flat-12]

After viewing your pictures, I went out to the garage and looked at my 2013 QP-S...and although I do not have any bubbling or anything, it is apparent that on the right side of the car (facing towards the front) there is evidence of contact between the boot lid and that trim piece. The bottom edge of the lid has tiny "specks" in the paint. I will apply touch up paint tomorrow and try to see the actual contact. Thanks for posting this issue makeshiftUK....

 

[flat-12]

Just a follow-up...as it turns out, there is no contact between the bottom edge of the boot lid and the trim piece. There is a gap between the two of about 3mm or so.

 

[makeshiftUK]

Thanks flat12. It’d be interesting to know if other QPV owners have seen anything similar to what I’ve got.

I’m not sure how the rear bumper is removed, but I imagine the slam cover exposes screws underneath - and maybe this action of removal/replacement of this cover contributes towards ill fitting and the accumulation of dirt, and subsequent ‘lifting’ (perhaps at some point in the cars history?).

 

[makeshiftUK]

Right. So started off the further investigation today with some fastidious cleaning of the boot/trunk area... I can only imagine the sorts of thoughts going through the minds of my neighbours who saw me (you should see their cars ). NB. the plastic trim seated in the train panels were utterly filthy, and needed a good vacuuming to get rid of the dust/mud/sediment that appeared to have collected over the years.

 

[makeshiftUK]

I then peeled off the plastic 'slam' cover - which was in very bad shape and went straight in the bin... a replacement as it happens isn't too expensive. I guess the downside to this is that there's nothing to absorb the impact of the closing boot... but I noticed there are rubber bungs each side, so not too bad an issue if a new piece of trim is installed in the short term, I guess.

The good news is that the bubbling/corrosion doesn't appear to be too far advanced - I feared that the trim was concealing further corrosion going further back. The bad news is that there appears to be evidence of this bubbling starting to appear further down the 'lip' of the bumper - the pictures explain this better. I'm hopeful a trip to the body shop won't involve removal of the rear bumper...

 

[Gazcw]

How is paint bubbling on a plastic bumper? Must be water getting in and just lifting paint.

 

[Oneball]

The boot lid shouldn’t be hitting the bumper or that bit of plastic trim. There’s buffers that should stop this. They’re usually adjustable or may have deteriorated with age, either adjust them or get some new ones or both

 

[Silvercat]

Thanks flat12. It’d be interesting to know if other QPV owners have seen anything similar to what I’ve got.

I’m not sure how the rear bumper is removed, but I imagine the slam cover exposes screws underneath - and maybe this action of removal/replacement of this cover contributes towards ill fitting and the accumulation of dirt, and subsequent ‘lifting’ (perhaps at some point in the cars history?).

When I had my 2009 QP, I also noticed a small patch of bubbling paint on the RH vertical face of the rear bumper which disappeared during hot weather. So more like small water blisters. I thinks it's a plastic bumper so it shouldnt be corrosion.

 

[makeshiftUK]

The boot lid shouldn’t be hitting the bumper or that bit of plastic trim. There’s buffers that should stop this. They’re usually adjustable or may have deteriorated with age, either adjust them or get some new ones or both

Yep, I referred to them as bungs in my above post - but whatever they're called, yes, they should stop any damage.

Hopefully the 'lockdown' will ease up sooner rather than later to get some bodyshop time booked in.

 

[flat-12]

Is it possible that the bubbling areas were subjected to some kind of corrosive substance / chemical? Something nasty that was washed down the boot rain channel or something leaked out of a container as it was being put into / removed from the boot?

 

[makeshiftUK]

Is it possible that the bubbling areas were subjected to some kind of corrosive substance / chemical? Something nasty that was washed down the boot rain channel or something leaked out of a container as it was being put into / removed from the boot?

Whilst it's possible, and aside from the usual bird s*** nothing comes to mind. I think where the plastic trim was re-fitted at some stage in it's life an opportunity has arisen for dirt/water to become trapped underneath, causing the bubbling I see on my bumper today.

I did notice that when I took the trim off, additional adhesive stickers had been applied on the underside resulting in a not-so-snug refit.