You need foresight and planning when performing repairs with salvage parts.
Ol' Harold calculated roughly as he sat on his overturned wooden milk crate, dual-action orbital sander in hand, staring at this latest project. The crate-the kind that Harold and antique collectors like-was covered with a fender cover. He sat there quietly pondering a question while he worked the sander over a Chrysler quarter panel. The question had come from a woman who had parked her mud-encrusted Jeep Wrangler just outside the door: "Can you fix my fender? I hit a deer."Experience taught Harold that the damage possibly rippled down farther than it appeared. The fender was caved, the hood dented and even the cowl may have moved. Harold had experience with many vehicles that had suffered from encounters with whitetail wanderers. After rising and pondering the four-wheel-drive vehicle, he phoned to investigate the potential availability of used parts, and the cost to this woman's pocketbook. Knowing that both her grandfather and father referred her, he grinned slightly. Harold simply grabbed his estimate sheets and said, "I can fix this 'Bambi bounce' with a few salvage parts."
In making repairs, we are often called upon to consider and investigate salvage parts. Harold soon found that he'd accepted this job almost too easily. Though the Jeep model was popular, getting a salvage part wasn't as easy a task as it seemed at first. Getting a good, usable salvage part for the left front of the Wrangler was difficult. The shop sits in an area of our nation known for deer damage and four-wheel drive (4-WD) vehicles that slide in snow and anti-skid chemicals.
A trophy? Or atrophy?
But why consider salvage parts? That's easy. For many shops, when a vehicle comes in for repair there is a tendency to be steered toward using new replacement parts. With new parts, we know that the tooling used to make the parts and the part itself is usually of high quality. Generally, it has the "fit and finish" of a new vehicle. The surfaces are normally protected for shipping, the character lines are true, the mating edges and flanges are within close tolerances, and the shipping container usually protects the part. After the production year for the tooling passes, making these replacement parts may be relegated to a factory subsidiary or independent parts supplier. At first, they make high-quality parts, but then tooling and die usage takes a toll. Die guiding plates wear, hole punches break, flanging steels round and character line tolerances drift. But often, the hunt for a salvage part can provide us with better ammunition for the job. It is possible for a salvage part to become better in quality than a new replacement.Bang for Your Buck
When ordering the part, like any new replacement part, you'll need to inspect and ensure that you get a usable piece. Clearly express to the supplier the need for the part according to its year, make and model. Remember, however, that many parts that are similar have varying model applications, emblems and trim. Usually a qualified salvage part supplier has good catalog info on interchangeable parts.Remember that some parts are more readily available, while others-like Ol' Harold's Jeep repair-may require an extended search. For example, since most hits occur at the left front of a vehicle, it would tend to offer that your search for a left front fender for a late model vehicle be more extensive than for a right rear panel. In any case, a reputable salvage parts dealer can usually tie into a network of yards to haul in the carcass that you need.
After you order the salvage part and it's delivered to your doorstep, inspect the part carefully. Is it dented? Bent? Is the trim applicable to the job? If so, is it removable and reusable for part refinishing? If different trim is needed, will any present mounting holes need filling and new holes installed?
If it's a structural part, ask yourself if the part is a high-strength steel (HSS) piece. If any straightening of the part is required, heat is an issue for HSS parts. It's crucial to remember that a 2-in. margin must be kept between the HSS part and a cutting heat source, according to I-CAR. A plasma arc cutter or oxyacetylene torch may be used for the initial cutting of recycled assemblies, provided the cut is at least 50 mm, or 2 in., from the final cut location. A cutoff wheel or grinder are the best options for making final cuts and trimming, I-CAR also confirms.
You should also ask yourself whether a part was removed by drilling the welds and if cutting out the part left you with this space to spare? Inspect carefully!Is the part rusted? In our case, the Wrangler parts had begun to show some rust deterioration, but had not suffered as much abuse as the original. With a little grooming and proper rustproofing techniques, the parts could bring in a "trophy hunt" rating.
Indeed, if the part meets your shop's standards, decide now on your installation, corrosion protection and refinishing techniques. For example, some repair shops will recoat over a previously painted late model part simply by sealing, primer surfacing, sanding and painting. Remember, most OEM and aftermarket part manufacturers' production methods include a metal preparation which provides a clean, neutrally charged metal surface, whether the panel is zinc-plated or not. If it's not plated with zinc, the surface is usually conversion-chemical treated to bond a thin coating of zinc phosphate on the metal panel. Then an E-coat, zinc-rich base primer is usually applied, to which you may apply a primer surfacer in preparation for top coat application. Thus, depending on the integrity of the original finish and its compatibility with your repair products, some repairers leave this factory quality coat and refinish over it.
Other body repair technicians, like Ol' Harold, say that you should use a complete refinishing system. No matter how old the part, take an orbital sander or paint remover, and remove the topcoat and substrate all the way down to the bare metal. As Harold pointed out, this is where you may find that previous repairs have been done on this part when several coats of paint and body filler begin to fly. If necessary, adequately remove any filler and do a new straightening and filling repair, or get another part.
Make sure the salvage part, and those items to which they attach, retain or regain their original shape. For example, a rear rail section we obtained for a repair came from a vehicle that had a hard front collision. We knew this from the kink evident in the salvaged right rear rail. As you may already know, collision impact travels through the body crush zones and can make the roof kink at the center pillar. The force transmits the impact around the passengers to the rear structure of the vehicle to kink the rear rail. Always inspect closely.Once the part is deemed as acceptable, mount the part with clamps and check the fit. This is where a high-quality salvage part hunt can bring home a trophy. According to Stephen Swartz, of Swartz's Ultimate Collision Repair in Danville, Pa., using salvage parts is a matter of fit and finish. Stephen pointed out a Blazer with a newly straightened windshield pillar, that already had the left front fender and door hung in place and fitted. Now, once fitted, the fender and door were again being removed for the refinishing process. Yes, it does take a bit more time. But, according to Swartz's, the quality difference is evident.
Now remember, for many parts, welds are the nuts and bolts of the unibody vehicle. Automakers spend time, energy and money to provide strong welds and a corrosion-proof car. In using a salvage part, you are to duplicate the effort. Properly corrosion-protect your customer's car as you do the repairs.
After removal of the damaged panel, properly prepare the salvage part for installation welding. Be sure you work cleanly. Once molten, a metal weld puddle must not be contaminated with atmospheric air, dirt, body sealer or excess metal plating. Admittedly, a metal-inert gas (MIG) welder can weld through rust, dirt and other junk, blowing away the ash. This is because MIG welding provides a pressurized gas to keep air away from the weld puddle. The gas is designed to prevent oxygen and nitrogen contamination, not to clean your part as you weld. So, why add weld contamination by using a dirty salvage part?
Do the job right, first by lightly scorching the paint and surface area with a torch. Next, remove the burnt materials using a wire brush. If needed, grind lightly to clean all remaining coatings. Clean both sides of a mating flange.
Now, questions have surfaced about the complete removal of zinc-plated corrosion protection. Do you remove the zinc coating to prepare for welding? Or should you leave it on the panel and weld through it? I-CAR suggests leaving existing zinc coatings in place when possible. However, welding through zinc produces noxious fumes, so a welding vapor mask should definitely be worn. If you are removing the zinc, before any welds are made, the coating may be replenished somewhat. Spray on a zinc-rich, weld-through primer, allow it to dry and clamp the flanges together for welding. I-CAR, in a change to their previous recommendations, now says the weld-through primer should be removed from the immediate weld area to minimize contamination of the weld itself. Remove any nearby components that might be damaged by welding heat or magnetic surges.
Take Good Aim
As you weld the salvage part, use heat control just as you'd use for new parts. Drill holes for sheet metal screws in the adjacent panel for every other spot weld removal hole you drilled in the old panel. Install screws to hold the joint tightly for welding. Make sure the filler rod is compatible with the body metal and the welder settings are correct. Weld a hole next to a screw at one end of the piece, a hole on the other end, and then one in the middle. This lessens heat buildup. Now, remove the adjacent holding screws. If the part is small, weld a little, then stop for a cooling period. Especially, use heat crayons to ensure there's no overheating of an HSS part. Weld until all screws are removed and holes are filled.Remember that butt and lap welds are used by carmakers in some pillar, center-post and floor pan areas. MIG butt and lap welds are preferred to duplicate these. But, be sure to clean old coatings at least 2 in. on either side of the area where you will weld. As before, pre-coat with zinc-rich primer, let it dry and clamp it. Weld a 3/4-in. long bead, then stop. Use heat control crayons. Weld a section, move to the middle, and then the end. Don't weld for more than three minutes. If it takes longer, stop and let the part cool before continuing. Measure as you go to ensure correct positioning. With MIG welding, periodically test your weld strength with scrap panels to ensure a strong bond. Conditions change, settings move and filler composition alters slightly; and all these items affect the weld strength.
After the welds are completed and cleaned thoroughly, the outside of all panels must be primer protected. Remember, some primers are porous and thus not moisture barriers. Use rust preventative type sealer/primer and also seal inner areas of the repairs. Sand all external surfaces as needed and prepare to refinish the repair.
Lastly, after refinishing, coat the area inside the replaced panels with a thixotropic sealant. This coating may be applied through holes in the panel by mist spraying techniques. First, select a tip that will uniformly coat inner surfaces. Most spray tips are available in several patterns. Fill the sealer gun and set the pressure to obtain a uniform mist. Plan the panel holes you are going to use and your pattern of spraying.
Don a respirator mask and coat the inner surfaces with a 1.5 mil to 4 mil. coating. Insert the tip into the panel and pull the trigger. Pause a second for the tip to begin spraying and withdraw it slowly. Practice will perfect the rate. But, don't apply the material too thickly, it won't do a better job. Remember, this stuff is thixotropic, which means the coating will creep into all the nooks and crannies and provide long lasting-rust protection for both new and salvage parts. Take the task of rustproofing salvage parts as seriously as you do refinishing. The long-term effects can make a deer damage job, or any other use of salvage parts, into a full rack of quality work.
