Urethane Bumper Rehab

[Mister 4x4]

So I have a salvageable urethane bumper, but I need to 'blast the bumper's metal frame, and get the bumper brackets removed to replace with new ones.

Anybody have a clue on how to take the urethane part off?

How about just getting the bolts loose without some kind of special tool or simply cutting the off? Cuz I'll do it... I swear... I have new nuts, bolts, and washers and no regard for rusty ol' stock fasteners... rofl

 

[Jeff73Mach1]

The bumper on a 73 has a pair of inner steel structures. Only the rearmost one comes out.

With your 72 bumper I don;t know if you can remove any of the steel structure.

When removing the rusty old bumper bracket bolts from the front frame rails, use a penetrant for a few days and use a torch to heat them up.the nuts welded inside the frame can break loose if you just use brute strength.

 

[pegasus]

here is a Mustang Monthly article on refinishing the polly front bumpers. might be of some help....

http://www.mustangmonthly.com/howto/75418/viewall.html

 

[Tnfastbk]

You can remove the metal section, by removing the giant phillips headed bolts. Like mentioned try soaking the over night with someting like Kano Kroil. Its the best stuff I have ever used for something like this.

 

[marks73]

You'll also need an phillips with an impact. I've had good luck with it and a 3lb hammer.

 

[72HCODE]

The urethane bumper itself, has a metal structure, molded inside the rubber. there is no way to take that out and fix it. The inside structure can be rotted away. my original bumper i sent to a company that refurbs the urethane bumper for the mach 1 and for various dodge and Plymouth cars, they told me my inner structure was basically gone on one side and not to bother spending anymore money on it.

I kept the bumper and a guy came along that wanted to use it for Wall art since it wasn't good for a car anymore. he bought it and i put the money info finding one in good condition.

that was about 7 years ago and the prices were insane back then.

you can repair the rubber cover using various rubber resins designed for modern plastic bumper repairs. you mix the resin, goop it on and sand back, you have to use a special bonder that you spray onto the surface of the repair before you goop the resin on, but it fills nice and stays flexible and rubbery, urethane is very hard to paint correctly so thats why you see the bumpers with the paint always flaking off them. you have to use paint with Flex additive and the surface prep must be perfect. the more original paint that you sand to that is bonded to the surface you leave because paint will stick better to paint then the rubber even with primer.

 

[OMS]

The easiest way to remove the sieze phillips head screws and J nuts is.

DO IT QUICKLY , 1 at a time

Torch the steel J nut, they are thin - melt fast - won't restick to the stainless screw - use cold rag or water on the bumper side of the bolt.

I have seen guys cut them open and replace a rotted section of metal and re-bond that section back on.

 

[Spechti]

I had the same problem. The urethane coating on the steel core was separating from it because rust crawled between them. There were visible bubbles and waves visible on the urethane surface. Since the mach 1 bumpers get scarce to find and in my opinion it was not rusted beyond repair, I decided to fix it.

The rust was mostly in the corners, at the underside (where the bolt holes are) and heavily on the inside.



First I took a grindstone in a drill and cleaned the inside of the bumper. Then I cut away every urethane material to about 1 cm from the edge and also every loose part of it. I cut it generously.

The underside also had serious damage. I cut away three sections of rubber, the biggest in the center recess. The rust was ground off and also media blasted with a hand gun. Clean metal was treated with rust converter (fertan) and painted with rust preventive coating (like por15)

I have found, it really takes strong nerves and a tiger's heart to slice a classic mustang's bumper.



After the procedure and thorough drying of the paint, the cut out portions are bonded in again using a strong polyurethane adhesive. I used a black urethane that is used for bodywork, e.g. glass adhesive. Do not use a silicone mastic!

Sorry guys, no pics of this mess...

The refurbished bumper was sanded and coated with a slightly flexible filler, also on urethane basis. Anyway, this stuff is harder than the rubber beneath it and cracks if bent heavily. But adhesion is quite good when treated normally.



Then the bumper is painted again in Acapulco Blue.



The inside is painted satin black.

Enjoy!

 

[JasonE]

I'm starting to work on the front urethene bumper for my 73, but it seems to be glued / melted / tar stuck onto the metal bumper bracket where the four bolts on the bottom are at. I haven't reached inside to take off the inside bolts. How important is it to take the bumper off of the brakes to repair? Or, can I repair it on the bracket? And how hard can I pull on the rubber bumper to try to take it off without it tearing or breaking? I'm new at this ...

Jason

Life is a Work in Progress

 

[machattack]

I have a question on the urethane bumper. When I bought the car the bumper had a upward tweek on one end. I think some one jacked the car up on that end or something? Maybe it was in a wreck?

My question is if you took a string and run it down the face of the bumper centered? would the bumper normally be straight across ?  I cant seem to find a photo of a bumper straight on.

Thanks

 

[jpaz]

I have a question on the urethane bumper. When I bought the car the bumper had a upward tweek on one end. I think some one jacked the car up on that end or something? Maybe it was in a wreck?

My question is if you took a string and run it down the face of the bumper centered? would the bumper normally be straight across ?  I cant seem to find a photo of a bumper straight on.

Thanks

I have the answer to your question, but I do have a couple of straight on pics of my urethane bumper. I just had it redone last year. Hopefully this helps.

 

[machattack]

Thanks Jpaz!

Still a little hard to tell. If a straight edge is put lenght wise dead center of the bumper? is it straight across it or are the ends slightly upwards?

Jpaz, you know where Cedar Springs Mi is at? Thats where I graduated high school.

 

[jpaz]

Thanks Jpaz!

Still a little hard to tell. If a straight edge is put lenght wise dead center of the bumper? is it straight across it or are the ends slightly upwards?

Jpaz, you know where Cedar Springs Mi is at?  Thats where I graduated high school.

No problem machattack, sorry not much help. I’m sure someone will be able to answer your question.

Yes, I know Caesar Springs is in the Grand Rapids area. Very cool, small world.

 I’m about 30 miles northeast of Detroit by Romeo.

 

[cv_72mustang]

Hi,  I happened to be in the garage messing around and took these photos. I have 72 vert all original including the cracked bumper

Sorry, a bit burry. It measured 19.5" from the floor taken 2 inches from each end.  Took a measurement in the middle also 19.5".  The floor is flat and concrete.  Rough .. but it appears not to bend up. Maybe this helps.

 

[machattack]

Thanks guys!!! Its official the bumper steel support is straight and not swooped up on the ends. Now I can disassmbly mine and get the old girl straight.

Thanks Again

Rod and Sally

 

[Boss1Ray]

Just had to mention this old thread.

Lots of good related info!!

https://www.7173mustangs.com/thread-urethane-front-bumper--35314

Ray

 

[machattack]

Just had to mention this old thread.

Lots of good related info!!

https://www.7173mustangs.com/thread-urethane-front-bumper--35314

Ray

Thank you !!  I will do some reading.