Is your 2001 E320 Mercedes experiencing rough idling, shaky acceleration, or excessive vibration, especially when in reverse? If your beloved Mercedes-Benz has clocked over 50,000 miles, the culprit might be worn-out motor mounts. Leaking or collapsed motor mounts are a common issue in vehicles of this era, leading to metal-on-metal contact and those unpleasant vibrations. The good news is, replacing them yourself is a manageable DIY task that can save you significant money on labor costs. Based on personal experience, this guide will walk you through the process of replacing the motor mounts on your 2001 E320 Mercedes in about three hours.
Step-by-Step Motor Mount Replacement for 2001 E320 Mercedes
This repair, while seemingly daunting, is quite straightforward with the right tools and a bit of patience. Here’s how to tackle replacing the motor mounts on your 2001 E320 Mercedes.
Preparation and Access
First, ensure your vehicle is safely supported. You’ll need to access the underside of your 2001 E320 Mercedes, so ramps or jack stands are essential. Begin by removing the plastic splash guard located beneath the engine. This step is crucial for accessing the lower motor mount bolts. You’ll notice convenient access holes in the crossmember designed precisely for reaching these bolts. Using these access points will simplify the initial steps. For this job, investing in a set of ratchet wrenches will be invaluable, particularly when dealing with the upper bolts in tight spaces.
Passenger Side Motor Mount
The passenger side upper motor mount of your 2001 E320 Mercedes is most easily accessed from above. Remove the upper bolt along with the metal heat shield. Be prepared for a slightly time-consuming process here. Space is limited between the engine and the inner fender, often allowing for only very small turns of your wrench at a time. This is where ratchet wrenches truly shine, allowing you to work effectively in confined areas where a socket wrench simply won’t fit.
Driver Side Motor Mount
Accessing the driver side upper bolt is best approached from underneath the car. A key step here is to unbolt the AC compressor. Moving the compressor forward creates the necessary clearance to remove the driver’s side motor mount later. The compressor is typically held in place by just three bolts. For easier removal, it’s recommended to first take off the serpentine belt. While wearing gloves for better grip, you can manually pull the belt to relieve tension from the auto-tensioner, allowing you to easily slide the belt off. Once the belt is off, unbolt the AC compressor and carefully slide it forward to create working space. Now you can access and remove the upper bolt and metal shield for the driver side motor mount through the space where the compressor was positioned.
Engine Lifting and Mount Removal
With both upper and lower motor mount bolts loosened or removed, the next step is to carefully lift the engine slightly. Use a floor jack and a piece of 2×4 wood, approximately one foot long. Position the 2×4 across the oil pan, perpendicular to the driveshaft, to distribute the lifting pressure evenly. Raise the engine by about an inch. This lift provides the necessary clearance to remove the old motor mounts and install the new ones.
Removing the old mounts requires maneuvering them out of their positions. The passenger side mount is removed towards the rear, over the steering rack. The driver side mount is removed towards the front, in the space you created by moving the AC compressor. Both removals require some careful maneuvering as the fit is snug.
Installing New Motor Mounts
You might need to raise the engine another inch or so to create enough space for the new motor mounts to be installed comfortably. When installing the new mounts on your 2001 E320 Mercedes, pay close attention to the small post on the top of each mount. This post needs to align with the corresponding slot on the engine mount bracket. You’ll easily identify these alignment features during the installation process.
Final Assembly and Checks
Before fully tightening everything, hand-thread the top bolts first. This is crucial because torquing the bottom bolts prematurely might misalign the top bolts, making them difficult to thread correctly. Once all four bolts are in place and hand-tightened, proceed to torque them to the manufacturer’s specifications. Re-bolt the AC compressor back into its original position and remember to reattach the serpentine belt.
Reinstalling the serpentine belt can be done manually. By wearing a glove for better grip, you can pull the belt tight enough to move the auto-tension pulley sufficiently. A helpful trick is to insert a screwdriver handle into the space between the tensioner pulley and the water pump pulley to hold the tensioner in the released position. This provides just enough slack in the belt to slip it back onto all the pulleys. Remember to remove the screwdriver handle once the belt is correctly positioned! Finally, reattach the plastic splash guard under the engine.
Now, start your 2001 E320 Mercedes and experience the difference. You should immediately notice a significant improvement in engine smoothness, reduced vibrations, and a much more refined driving experience. This DIY motor mount replacement is definitely worth the effort and the money saved on labor charges.
Congratulations, you’ve successfully replaced the motor mounts on your 2001 E320 Mercedes! Enjoy the smoother ride.
