Under Hood Inspection Tips
Words and Photos: Mark Yanochko
An under hood inspection is a routine maintenance procedure that should be performed whenever other scheduled maintenance procedures are done. The most likely time to perform this task is when the oil is changed. Other opportunities would be when the battery is checked before the cold winds of winter arrive, or when an A/C performance test is done in the spring. Regardless of the timing, every time the hood is raised is a good time to take a look around the engine compartment, above and below.
Chrysler Group LLC dealerships have a standard multi-point inspection sheet that they use whenever a vehicle comes in for service. If you are an independent repair facility, you should have your own inspection form.
Okay let’s open the hood. The first thing to check is the wiper operation, windshield washer fluid level and the windshield wipers. Inspect the cabin air filter, if the vehicle being serviced is equipped with one (this is something that is frequently overlooked). Next, check the air filter, A, shown side-by-side with a clean one, B, in Figure 1. Don’t forget to clean the air filter housing.
Check the coolant level, C (Figure 2). Get your hydrometer, D, and check the temperature protection of the coolant (Figure 3). Then check all the coolant and heater hoses, along with the hose connections, like E, shown in Figure 4. Inspect the radiator core for any damage.
Another fluid to check is the brake fluid level. Be sure that the level is between the Min, F, and Max, G, marks (Figure 5). Also, check the fluid level of the power steering fluid. If you’re not changing the oil, check that level, too. The last major fluid to be checked is the transmission/transaxle fluid, if equipped with an automatic trans. Check all the fuel lines and connections, too.
Battery terminals must always be clean, especially in cold winter temperatures when more cranking amps are needed than in warm weather. Clean any corrosion, H, such as that seen in Figure 6. If the battery has removable covers, check the electrolyte level. Perform a storage capacity test to determine the serviceability of the battery.
Serpentine belts cannot be inspected by sight alone. These belts don’t necessarily show cracks when worn as the old V-belts did. Wear is the most accurate parameter to determine serviceability. A simple tool to check wear, J, is placed in one of the grooves (Figure 7). After it is in place, run your finger over the top of the stem. If the stem is below the top edge of the grooves, the belt is worn. Check the belt tension, too.
Before you close the hood, don’t forget to take a close look at the emission control devices. These include the purge solenoid valve, the PCV valve and the EGR valve, K (Figure 8). It’s important that the neoprene hoses are not cracked, split or show any other signs of deterioration. The vacuum hose, L, for a typical EGR valve is shown in Figure 8. Check the hose where it is connected to the component. That’s the most likely spot for the hose to fail.
