Nicole

Potentially, this technique could help a lot of 928 owners:

http://thegarage.jalopnik.com/yes-yo...-of-1731180291

Ed Scherer

It's really the music that motivated the bumper to pop back out.

The hot water was just for show.

MainePorsche

Makes sense.
It's at least worth a try if you're in that boat.

Speedtoys

Thats not a warp..thats a big ol fat dent.

SHould work..if not creased and long term in that shape.

bureau13

The thing is, a warp is not usually trying to spring back to its original shape, like that dented bumper piece. Can't hurt to try though.

slate blue

Hate to pour cold water on a potentially helpful idea but they are two different problems. Back when I restored my car about 15 years ago, the bumpers on my grey 84 MY car were pretty badly distorted. So bad I decided to buy brand new ones from Porsche. When I got the new ones I had to even fix them. I sanded the parts back that were distorted and filled them with the flexible bumper bar filler.

The problem occurs when they get to hot. I have found that white bars are the best to buy used. Also when the car went to the booth the heat applied to set off the paint distorted the bars that were perfectly straight before the heat was applied. The S4 bars and similar are better but the rears if subject to too much sun also distort. However these later bars tend to hold there shape better. I'm afraid bumper bar filler after the bars are stripped will be the only effective repair.

RennPartsDirect

Scalding hot water would be hard to direct IMO. A heat gun is a much better option: more control and much safer. It worked like a charm when my wife parked her car through a parking block and dented in the front bumper similar to that shown in the video...

sdamiani73

It's my first post here regarding Porsche 928 1st Gen Bumpers. I have a 1979 low mileage car which is immaculate , however both front and rear bumpers have tiny little stress fractures that look like spider webs. The panel shop completing the respray initially repair did a great job but when the car sat in the sun it starting showing these tiny little lines where the paint was drawn into the stress fractures. Any advice on how to cover these up with a special filler perhaps flexible?

wpgshark

Unlikely that hot water is going to restore a warp. Everything moves to a state of less energy. The warps occur because over time and with the addition of heat some of the tension holding the part in it's original shape are removed, and or new stressors or tension are added, the result is the panel moves to a shape that minimizes these forces.

The hot water can work on a dent as it can temporarily reduce some of the forces that are holding the dent as well as apply some expansion forces, which can result in the panel moving back to a shape closer to original.

There are some very good flexible glazes that can be used on urethane bumpers to fill spider cracks. It is time consuming finicky work. I suspect that the baking after paint may not be a good idea with older urethane and may contribute to future problems. I would lean to a longer lower temperature curing/drying method.

sdamiani73

@wpgshark | Thanks for the tips. The bumpers are in pretty good shape with no distortions, its just the spider cracks all other the bar which are driving me mad. I wonder if the best bet is to fill and sand using a flexible filler and then use a flexible glaze with slow curing. Sounds like a tedious job but I want to get it right. Any suggestions on brands would be appreciated.

wpgshark

http://www.evercoat.com/product-deta...ber/100411/us/

I've had good luck with this product, haven't used it on a 928 but will be using it shortly. Correct that I did use it to fill in some cracks on my pod before covering it in leather.

If you're just filling the spider cracks you shouldn't need to fill under this it has a good consistency and a really good stick. I used it to fill the spider cracks on my fiberglass bass boat before repainting and 3 years latter not one has returned.

Good luck.

the flyin' scotsman

After the 'hot water trick' theres copius live video of Bowie Id not seen before........thank you