2003 Ford Mustang Cobra Water Spot Removal

Water spots on your car is pretty common in South Texas.  With water levels reaching up in the 310 ppm (parts per million) in San Antonio.  With water hardness this high & the Texas heat its easy for a vehicles finish to get etching from water deposits.  Below is a chart that illustrates the water hardness & deposits that are in the water.  Taken from 2006-2011 by the San Antonio Water System (SAWS)



That’s a little info of whats to come regarding the issue at hand.   I was contacted about water spot removal on a 2003 Mustang Cobra since the car is going up for sale.  At first the car was a little dirty and didn’t seem that bad.  So we set up an appointment for drop off, which was approximately 1 month ago.

Water spots.

It doesn’t look too bad you would think.  So i get it washed and bring it into the bay and what we discovered after washing it was that it was a lot worse than we had thought.  The vehicle had been sitting for a long period of time and had come in contact w water & was never wiped down.  During this time the sun baked in the contaminants from the water and etched the finish.  Here is what we found to be working with once we started.

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Seeing this was gonna be no easy task. There was water spots every where. On the Paint on the trunk, door jambs, glass.  In some of the areas where the panels came together by the mirror & rear quarters, headlights there was a huge amount of build up of calcium there.  The film was evident visually & you could feel that on the finish of the vehicle that there was a film on there as well.  So my initial thought was to try to buff the hood out.   So after 2 hours of buffing i finished up a 2’x2′ square.  This was we came up with.

water spotsYou could say “wow thats a huge improvement” but i was really unhappy with the results so i consulted one of my good friends Kevin Brown, the topic came up on how we can remove the layer of film with out compromising the clear coat.  I had already tried buffing through the film and that wasn’t giving me the results i wanted.  Then i tried soaking the car in distilled vinegar and that didn’t do anything either.  Finally he brought up the idea of chemically stripping it with an acid based water spot remover.  We chose this method to remove a majority of the spotting to preserve the clear as much as we could.  So i started to disassemble what needed to come off.

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What were going to start with is the roof as shown in the picture below.  We wiped the area clean,  applied the water spot remover let it sit for a bit.  Then we proceed to wipe the water spot remover off and rinse clean with free flowing water to neutralize the acid in the water spot remover to not cause any damage.  Here’s the roof before.

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Here it is w the water spot remover on it.

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after a little agitation w a microfiber applicator and some water to rinse off.  Were left with a water spot free finish.  This acidic water spot remover has some ingredients in it that are designed to dissolve minerals like Calcium (Ca++), Sodium (Na+), Potassium (K+), and Magnesium (Mg++) Calcium and Magnesium are the most common.  Here’s what it looked like afterwards.

03 cobraNow that’e the improvement i was looking for.  The only draw back from this process is that it can leave the paint dry and create a haze that needs to be polished out.  Now we moved on to the glass which is the same process as above for the paint.

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So this process for the glass alone took approximately 2 hours with as thick as this etching was.  So when we had spare time we would work on a panel here and there.  Next up we started working on the doors working our way around the car.

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The rims on this car were just as bad.

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So 3 weeks later were at about a 90 improvement.  The other issue we had aside from removing water spots was now to address the dried up, hazed paint.

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Looks like someone wet sanded most of this car lol.  So we started with our polishing process and here you can see what a difference polishing makes. 014 (4)012 (5)

Now were getting somewhere!  At this point its getting to where i know the customers going to be happy.  So we proceeded to finish up the polishing the headlights, tail lights, the grills in the hood etc.

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boss, frsocpro 072here the front bumper has just been polished out, hasn’t been sealed yet.

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 When i had disassembled the vehicle i noticed that the plastic grills in the hood has water spotting on them.

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nothing a little Dupli-color plastic paint cant fix.041

As i finished up polishing everything up the customer is on his way. I re assemble the headlights, tail lights, doors & hood inserts.  Now Everything is all done and putting everything back on the car is complete and here is the final result.  Hope you’re as happy with it as i am.  I think it came out very good!

Thanks for reading.  This was probably one of those jobs that took longer than anticipated.  But since the original owner was selling the car and the buyer gave me time to do the job right.  It took me a little over a month to complete along with the customers cars i was doing on a daily basis.   Id like to say thanks for Kevin Brown of Buff Daddy, Greg Masterson & Jay Ortega from Chemical Guys in California for letting me pick their brain on what was going to be the best way to get this done and getting it done right.

Ill leave you with my favorite pic of them all.


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