e90 cracked rear bumper paint...

rabbler · 09-21-2009, 10:03 AM

Long time lurker, hoping you guys can help me out.

I live in the city, and park my car on the street. This morning when I got out to my car to go to work, I found that some guy in a mustang had trapped me in from the rear. Granted I should have given myself more room up front, but that's not necessarily the point. So I had to tap the bumper of the guy in back of me to get out, not necessarily hard but I felt it. It was a 4 point turn by the time I got out. The kicker is that he had about 5 feet behind him as a car couldn't fit between him and a driveway.

When I got out later to see if there was any damage, I noticed a crack in the bumper. Upon investigation just the paint had a 6 inch crack in it, not the bumper. I could pull back the paint just a little bit to see that indeed there was no damage to the bumper.

I asked some people, other than the normal responses of "key his car", one friend informed me of all of the "flexing agents" put into car paint so that paint cracks like that don't happen.

Question: Is this a manufacture defect?

Thanks.

F32Fleet · 09-21-2009, 11:44 AM

Usually normal. IIRC the bumper plastic is fairly flexible so it can take greater punishment than the paint.

jmd_forest · 09-21-2009, 03:11 PM

I do not know of any manufacturers using flex agent in their paint. Most modern urethane paints have a fair amount of flexibility. I would assume you hit an edge of some kind that caused the crack.

In cold weather moisture will get under the lifted paint and freeze, causing more lifting.

Only real fix is to sand out each edge of the cracked paint until you get to an edge with good adhesion, fill any void with flexible glazing putty, primer, sand out, and repaint. There are flex agents that can be added to the paint to make it more flexible for next time.

jmd_forest

FCP Euro · 09-21-2009, 07:10 PM

I don't see that as being a defect in the paint. I am surprised it did not do more damage. I would just have a body shop fix it and just remember next time to give yourself more room.

rabbler · 09-24-2009, 02:32 PM

One can only hope.

It did happen to be the first cold morning around here when it happened. meh. Live and learn; never park by a mustang.

09-21-2009, 10:03 AM	#1
rabbler Registered 0 Rep 2 Posts Drives: 06 E90 330i Join Date: Sep 2009 Location: US iTrader: (0)	e90 cracked rear bumper paint... Long time lurker, hoping you guys can help me out. I live in the city, and park my car on the street. This morning when I got out to my car to go to work, I found that some guy in a mustang had trapped me in from the rear. Granted I should have given myself more room up front, but that's not necessarily the point. So I had to tap the bumper of the guy in back of me to get out, not necessarily hard but I felt it. It was a 4 point turn by the time I got out. The kicker is that he had about 5 feet behind him as a car couldn't fit between him and a driveway. When I got out later to see if there was any damage, I noticed a crack in the bumper. Upon investigation just the paint had a 6 inch crack in it, not the bumper. I could pull back the paint just a little bit to see that indeed there was no damage to the bumper. I asked some people, other than the normal responses of "key his car", one friend informed me of all of the "flexing agents" put into car paint so that paint cracks like that don't happen. Question: Is this a manufacture defect? Thanks.
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09-21-2009, 11:44 AM	#2
F32Fleet Lieutenant General 3570 Rep 10,351 Posts Drives: 2015 435i Join Date: May 2005 Location: Southeastern US iTrader: (0)	Usually normal. IIRC the bumper plastic is fairly flexible so it can take greater punishment than the paint.
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09-21-2009, 03:11 PM	#3
jmd_forest Enlisted Member 5 Rep 45 Posts Drives: 2008 328xi Join Date: Jun 2009 Location: South NJ iTrader: (0)	I do not know of any manufacturers using flex agent in their paint. Most modern urethane paints have a fair amount of flexibility. I would assume you hit an edge of some kind that caused the crack. In cold weather moisture will get under the lifted paint and freeze, causing more lifting. Only real fix is to sand out each edge of the cracked paint until you get to an edge with good adhesion, fill any void with flexible glazing putty, primer, sand out, and repaint. There are flex agents that can be added to the paint to make it more flexible for next time. jmd_forest
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09-21-2009, 07:10 PM	#4
FCP Euro Lieutenant 10 Rep 462 Posts Drives: Volvo 850 T5 Join Date: Aug 2009 Location: Old Saybrook, CT iTrader: (0)	I don't see that as being a defect in the paint. I am surprised it did not do more damage. I would just have a body shop fix it and just remember next time to give yourself more room. __________________ sales@fcpeuro.com FCP Euro - European Car Parts Specialists
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09-24-2009, 02:32 PM	#5
rabbler Registered 0 Rep 2 Posts Drives: 06 E90 330i Join Date: Sep 2009 Location: US iTrader: (0)	One can only hope. It did happen to be the first cold morning around here when it happened. meh. Live and learn; never park by a mustang.
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