Rust never sleeps, transfer case mounting and dual shifters in this installment of ‘Tech Tips’

Something not right with your historic military vehicle? Steve Turchet answers your questions on how to keep ’em movin’!

Rust Never Sleeps

When moisture gets on most ferrous metals, such as tools or vehicle parts, the result is an oxidation process… or simply, rust. Serious rust with scale often requires heavy-duty methods to remove, such as power wire brushing or sand-blasting, and even then the tool or part may have pitting, which can leave it weakened at worst or cosmetically damaged at best. However, surface rust can often be removed with ordinary household products. Be aware that none of these methods will remove grease, oil or caked-on dirt, so the items must be cleaned first.

Baking Soda: Rinse the item with water and shake off the excess. Dust it with baking soda, which will stick to the dampness, making sure to cover all rusty areas. Leave the item for an hour or so, then scour with steel wool or a wire brush, removing the rust down to clean metal. Rinse, and towel dry. Best used on light surface rust and thin metal. Advantages: simple method using a cheap, common ingredient. Disadvantages: takes at least an hour before you can start cleaning away the rust.

Vinegar bath: Submerge the item in white vinegar and let it sit overnight. Remove the item and clean off the rust with a wire brush or steel wool. Best used on significant rust found on tools or items that are all steel and can be submerged without compromising the integrity of other surfaces. Advantages: easy “let sit and forget” method. Disadvantages: the item needs to soak at least overnight.

Potato and dish soap: Cut a potato in half and cover the open end with dish soap. Use the potato like you would a scouring pad and watch the rust fade away as it reacts with the soap and potato. Best used on small areas of surface rust stains.

Advantages: Simple and relatively fast method for removing rust. Disadvantages: messy, work over a sink or somewhere where cleanup is easy.

Citric acid: May not be in your house, but can be found at most health-food stores. Add a few inches of hot water to a bowl and sprinkle in two or three tablespoons of citric acid. Submerge the item and let it sit overnight, then scrub off lingering rust flecks with a wire brush, rinse, and pat dry. Best used on tools or small items that can be submerged without compromising the integrity of other surfaces and coatings (citric acid will remove paint). Advantages: another “let sit and forget” method. Disadvantages: many people won’t have this ingredient in their house.

Lemon and salt: Liberally coat the rusted area with a layer of salt. Cut a lemon (or lime) in half, and squeeze the juice over the salt. Let the mixture sit about an hour, then scrub away the rust with the lemon rind. If rust remains, repeat the procedure and let the salt and juice sit for another hour or two until the rust disappears. Rinse with water and pat dry. Best used on light rust stains. Works great on tools or parts that have small patches of rust here and there. Advantages: minimally abrasive process, and uses items you’ve probably got at home. Disadvantages: if you’re scrubbing rust off something sharp like a knife or saw blade, use care not to cut yourself.

Brake fluid: Ordinary brake fluid (not silicone) will do a surprisingly good job of removing rust. Submerge the item in brake fluid and leave for a few days, then rinse with solvent and wire brush clean. Also an effective method to free an engine with stuck pistons. Remove the spark plugs and fill the cylinders with brake fluid. Let sit for a few days. Advantages: yet another “let sit and forget” method. Disadvantages: takes days or a week to work. Brake fluid will also remove paint.

Small Hole Into Big Hole

Q: I have a 1968 International Scout 800 that was used by the Army as a GSA vehicle. I bought it many years ago at a surplus sale. The transfer case finally gave up with broken gears. A friend gave me a good transfer case from an M38 jeep but when I went to put it in I found that the opening where it goes on the transmission is smaller than the old transfer case. I guess I could take all the parts out of the “new” transfer case and but them in my old one but I wonder if I could just make the hole bigger in the “new” case?

A: The Dana/Spicer model 18 comes in two basic flavors, commonly know as The “small hole” and “big hole.” The small hole is three inches in diameter, the big hole four inches. It’s probably not beyond your mechanical skills to install the “new” components into you old “big hole” case, and detailed instructions can be found on the Web. Most well-equipped machine shops can bore the small hole into a big one, but that may be expensive. A very crude method is to make a guide template to accurately mark the new opening with a scribe, then carefully drill a series of holes all around to enlarge the opening, and smooth with a half-round file. I made a special tool for enlarging the opening using a 3 inch and a four inch metal hole saw blades. The smaller blade acts as a guide for the larger. Cast iron is soft and easy to drill, but use slow speed and LOTS of oil, and remove the saw often to clean the drilled metal out of the groove. Last one of these I did took about half an hour to carefully drill.

A Little Less Frustration

Depending on the type of vehicle, installing the two shift levers on a Dana/Spicer 18 transfer case with the case in the vehicle can be a frustrating process because of the anti-rattle springs, especially if you’re working from underneath. This job can often be make easier by securely taping, using electrical tape, the springs to the levers, using the pivot shaft to align them, before trying to install the levers. Then use a knife or razor blade to remove the tape.

Send your favorite Tech Tip or question to Steve Turchet at military@aimmedia.com

Looking for more Tech Tips? here are a few more for your reading enjoyment.

Send your photos to MVM