If your Mitsubishi Pajero NM or NP is experiencing brake issues like a hard pedal or the brake warning light coming on, or even a loud screeching noise that sounds like a screaming bird, it might be time to replace the brake accumulator. This guide will walk you through the process step-by-step.
Safety First
Before you begin, ensure the vehicle is on a level surface, the parking brake is engaged, and the engine is off. Working with high-pressure brake systems requires caution.
Step 1: Locate the Brake Accumulator
The brake accumulator is a black, spherical component mounted on the side of the brake master cylinder assembly in the engine bay.
The brake accumulator is the large black sphere located on the left side of the image, attached to the master cylinder assembly.
Step 2: Depressurise the Brake System
This is a crucial safety step. With the engine off, pump the brake pedal repeatedly (usually 20-30 times) until the pedal feels very hard. This releases the stored pressure in the system.
Ensure the system is fully depressurised by pumping the brake pedal until it becomes firm.
Step 3: Remove the Old Accumulator
Once the system is depressurised, use a suitable wrench (often a large adjustable wrench or a specific size socket) to unscrew the old accumulator from its housing. Be prepared for a small amount of brake fluid to escape.
Carefully unscrew the accumulator. You may want to place a rag underneath to catch any spilled brake fluid.
Step 4: Install the New Accumulator
Install the new brake accumulator. Ensure you use a new O-ring, which is typically supplied with the new part. Thread it in by hand first to avoid cross-threading, then tighten it securely with your wrench.
Screw the new accumulator into place. Don’t forget the new O-ring for a proper seal.
Step 5: Final Checks
After installing the new accumulator, check the brake fluid level in the reservoir and top it up if necessary. Start the engine and pump the brake pedal a few times to repressurise the system. Check for any leaks around the new accumulator. If everything looks good, you’re all set!