Tuesday, May 15, 2012

1971 GTX - Beginning the restoration By Roman Sobilo

Hello everyone.  My name is Roman from After Hours Restorations in Detroit.  In these next four issues of Chrysler Power I will be writing about a currant restoration that is taking place at my shop.  I will divide the complete restoration up into these four categories:

  • Deconstruction & metal work
  • Body & paint work
  • Interior & component restoration
  • Drivetrain & assembly

The car I am currently restoring is a 1971 GTX.  It was an unmolested car retaining its original numbers matching 440 engine and 727 torque flight transmission.  The body had some patch work done to the lower fenders, doors, and quarter panels.  It was repainted once in the original color and some minor repairs were done to the interior (front seat covers and carpet). Besides the repairs mentioned it was just a nice original car that read 23000 miles on the odometer.  Although it is not verified I do believe this is a 123000 mile car that somehow was able to avoid headers, an aluminum intake and a Holley carb. 

Each restoration has its own special circumstances.  It is important to take a step back and analyze the current situation before any crucial information is disturbed.  Deconstruction is one of the most important parts of a restoration.  Some of the most important and helpful information will be obtained in this first part of the restoration.

A digital camera is the most useful tool in the deconstruction process.  When I began disassembling a car for restoration the digital camera is always within arm’s reach.  I typically take approximately 500 pictures during this process.  Factory inspection marks and date code stamps are the first things I document. 

Body panel and glass fitment are two other important items I recommend you document.  During the assembly process, adjusting quarter and door glass is where I spend most of my time.  At the end of my struggle I usually realize an optimal adjustment was achieved hours ago.  This is a good way to weed out preexisting factory issues during the assembly process that can have you beating your head against the wall. 

Once I have all of my documentation completed the actual deconstruction starts.  I must admit busting out the air tools with a five gallon bucket to catch all of the fasteners flying of the car sounds like a good weekend but the end result would be awful. 

So, before you start disassembling your car purchase a few boxes of plastic baggies and a pen.  Bag and label everything!  Don’t fool yourself into believing that you will remember, because you won’t. 

To keep the disassembly process simple I take the car apart in the opposite order the factory uses to assemble the car.  Now don’t get me wrong, I don’t have a clip board with step by step factory procedures to check off once completed.  I just try to use common sense. 

For example I will not start the disassembly process by taking the hood off and just pulling the engine out of the engine compartment.  My approach would consist of dropping the complete drivetrain out from the bottom of the car.  I usually perform this step after the fenders are off of the car to prevent any accidental damage.

I fabricated a metal fixture that bolts to the front frame rails using the bumper bracket bolts.  An engine puller is then used to lift the car high enough to roll the drivetrain out from under it.  The fixture is nice but not necessary.  Before I took the time to make the fixture I used a set of old bumper brackets hooked together by a chain.

Once the drivetrain is rolled out from underneath the car separating the engine, transmission, and all of the front end components has just become that much easier.  If available, document important information on the drivetrain assembly.  Note what components were on the engine when the factory painted it and look for any factory markings.

The dashboard is another part of the car I prefer to tackle as a subassembly.  Once the front windshield is out of the car pulling the complete dash is easier than disassembling it with the frame bolted in the car. 

Remove the center support brace and loosen the two bolts above the kick panel.  The two steering column studs must also be removed from the brake pedal assembly.  Remove the five bolts on top of the frame and use a hook made from an old coat hanger to keep the dash in place once it is rolled back.  Now with the das rolled back you have plenty of room to disconnect the defroster tubes, heater box cables, the radio antenna, and bulkhead.

Once everything is disconnected simply remove the coat hanger and pull the dashboard assembly out of the car.  Now you can have the comfort of disassembling the dash on a bench instead of lying on your back!  

Once the GTX was a disassembled shell I had it media blasted before the metal work began.  Chemically stripping the shell is also an option.  There are pros and cons to both methods.  I have heard horror stories about both.  I have also used both methods with successful results. However, there are a few points I would like to discuss.  Media blasting is a great way to strip a shell.  I use this method 90% of the time.  As you shop around for a media blasters don’t get caught up on the price.  Focus your thoughts on who is going to be doing the work.  Let’s face it; media blasting is not the most desirable work out there so it is common for a big turnaround in employees.  The new employee has to learn on someone’s car so make sure it is not yours.

SS Media Blasting in Sterling Heights Michigan is where I take all of my shells.  Since flat outer panels are easy to warp they use one experienced guy to blast all of the outer flat panels and all the new guys to work on the secondary panels such as the trunk, engine compartment, and undercarriage.
Again you must step back and analyze your current situation.  Media blasting cannot effectively clean the inside of a frame rail or rocker panel.  If you have a severely rusted car you may want to consider chemically stripping it.
Chemical strippers are usually more difficult to find due to EPA regulations.  Submerging the shell in chemicals will strip the metal of any rust.  However, the shell is constructed of spot welded overlapped sheet metal.  Once submerged in liquid the overlapped sheet metal can trap the chemical causing it to seep out at a later date.

Seeping can be avoided if the shell is properly cleaned, rinsed and dried.  If you decide to chemically strip the shell you must use some sort of coating or rust inhibitor inside the frame rails and rockers.

The size of the shell or car body must also be considered as you shop around for a chemical stripper.  Many strippers don’t have tanks big enough to fit a uni-body without putting it in on an angle or its side.  Doing so increases the chance of damaging the shell.

So once I brought the GTX back from the media blaster I asset the damage and decided to replace the driver side quarter with a full replacement panel.  Since the passenger side was not as bad it was repaired with patch panels. 

The first thing I did was cut approximately 8 inches off of both quarter panels exposing the inner rocker panels.  I cut just enough to expose the inner rocker and no more.  This will keep the cars integrity and strength so it can be transported back to the media blaster without welding in any special braces or supports.   

Since the GTX was media blasted the inner rockers were covered with surface rust.  At this point I took the shell back to SS and had them blast the inner rockers I exposed.  Once the GTX was back at the shop I used a strong bonding chassis paint to cover the inner rockers.  Notice no paint was put on the surface that I will be welding on.  All overlapping welding surfaces were covered with weld through primer.

Inner rocker coated with chassis paint
New patch panel installed
A huge amount of water is drained between the inner rocker and the quarter panel when the car is washed or driven in the rain.  It is important to clean this area of any rust and coat it properly to avoid any future issues.
Since the driver side quarter was repaired with a full panel I was able to weld on areas that would not be visible once the car was assembled.  Drilling a hole through the top panel and puddle welding it was the method used.  The passenger side patch panels were butt welded.  After I ground the weld down on both the inner and outer side it is very difficult to detect any panel replacement.

Now that all of the metal work is done the shell is ready to go back to SS Media Blasting for a third time to be cleaned of any rust which reappeared while the metal work was performed.   Once SS is finished freshening up the GTX it will go directly to the body shop were the transformation from a bare hunk of metal to a beautiful GTX will began.
I hope you found this restoration talk helpful.  Comments and feedback are always welcomed at roman@afterhoursrestorations.com.

Next issue body & paint work!

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