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Should I be worried about rust on my car’s calipers?
John Paul, AAA Northeast's Car Doctor, answers a question from a reader with concerns about visible rust on his car’s calipers.
Q. I changed the calipers, rotors, brake pads, and both back tires of my 2012 Acura TL last December. The work was performed at a AAA repair shop. Now the calipers look completely rusty. What should I do now?
A. Surface rust is not too serious, it is more the caliper slides that you need to make sure are properly lubricated. Certainly, you could take off the calipers and paint them to prevent more rust. Rust-Oleum makes a high temperature caliper paint. The rusting issue is typically caused by ice-melting chemicals. The latest replacements for rock salt – such as calcium chloride and magnesium chloride, often in liquid brine form – are great for road safety, but tough on car parts and bridges. You certainly could stop at the repair shop, show them the calipers, and ask if they have had any issues with that part or supplier.
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Q. I have a 2020 Subaru Forester, and when it was in a local shop for an oil change the technician showed me some cracking in the front suspension bushing. He said it was not serious, but it is something I should take care of in the future, maybe by year end. Any thoughts on this?
A. Some cracking in rubber bushing is normal and to be expected with age. If you take a screwdriver and stress the crack and it goes completely through the bushing, the bushings need replacement. In fact, Subaru states cracks with a width greater than 13mm (1/2 inch) will have an impact on the vehicle ride quality and will require replacement. Cracks with a width of 13mm (1/2 inch) or less will not cause any functional concerns and will not require replacement.
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Q. I had an issue with my car running rough. I went to the dealer to ask about service, and they suggested that the car has excessive carbon build up. They recommended cleaning using walnut shells. What do you know about this?
A. Years back the engine combustion chamber and specifically the intake valves would build up with carbon deposits. The issue was mostly solved with gasoline with a higher percentage of cleaning additives. Today we are seeing a similar issue with direct injection design engines. Direct injection engines are prone to carbon buildup because fuel is injected directly into the cylinder, rather than at the intake valves. This lack of fuel cleaning additive at the valves and ports leads to more combustion deposits over time. The walnut shell blaster is used once the intake manifold is removed to blast off any deposits. I first heard about walnut shell blasting to clean carbon buildup in aircraft engines. The walnut shell abrasive can be easily targeted to the valves and without causing damage to any other parts.
Q. I recently purchased a lightly used Ford Transit van that was owned by a caterer who purchased it new. I like the truck. It works out great for my work and for bringing my art to flea markets. The one odd issue is, on warm days when I have the air conditioner on and I sit parked, I hear a weird noise. It sounds like dripping water on a hot pan. Any ideas?
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A. You are exactly correct. It is water dripping, but not on a pan but on the exhaust system. When the air conditioner is working it removes moisture from the air and that moisture drains on the ground. The air conditioner evaporator drain hose needs to be lengthened and repositioned to allow the water to drain without hitting the exhaust.
Q. I just purchased a 2012 Volvo S60, and it is really a great car. It feels solid and gets decent mileage, but there is one issue that bugs me. There is no exterior trunk lock. Can a lock be added?
A. From what I have gleaned looking this up, the lock is there, but there is no access to it. The trim piece needs to be removed, and a hole drilled and then you have access to the lock. The lock is then covered with a plug to keep things weather tight.
Q. I recently inherited an old Jeep. It was a former Army Jeep, and it looks like it is in good condition, sort of. The brakes are shot, and the engine is stuck. The brakes look simple enough to fix, but the engine has me concerned. Any idea where to start to free this up?
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A. I would remove the spark plugs and add Marvel Mystery oil to the cylinders. Or you could make your own cleaner. Mixing a 50/50 mix of transmission fluid and acetone also works well. Add this to the cylinders and let the mixture do its magic overnight. The next day try rotating the engine by hand. Go a little in each direction until you can make a complete revolution. Add more Marvel Mystery oil or the homemade mixture and rotate the engine until it feels smooth. Once everything is moving then you can move onto fuel and ignition. When you get it running there will be a lot of smoke from the oil, but it should clear up over time.
John Paul is AAA Northeast’s Car Doctor. He has over 40 years of experience in the automotive business and is an ASE-certified master technician. E-mail your Car Doctor question to [email protected]. Listen to the Car Doctor podcast at johnfpaul.podbean.com.
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