Four Post Lifts
Four post lifts are often used for medium duty truck applications and are commonly found in muffler, oil change, transmission and alignment service shops. As with two post lifts, it is imperative that shops follow a regular routine for lift inspections, service, and maintenance to prevent expensive and unwanted down time.
The following are problems and causes affecting four post lifts. If mechanics spot any of these conditions, repairs need to be made immediately:
Problems:
1. Pins are not flared on the chain
2. Chain is not connected to connectors/anchors/studs
3. Chain loses flexibility
4. Chain prematurely worn
5. Bearings worn out or collapsed
Causes:
1. Top rail unlevel
2. Exposure/weather conditions
3. Lift overloaded
4. Installation errors
Solutions:
1. Replace lifting chain sets
2. Install new chain roller bearing sets and axles
3. Properly lubricate chains to prevent binding
Problems:
1. Noises (popping)
2. Bearing edges chipped
3. Bearings worn or unlevelled
4. Bearings not turning/rotating smoothly
Causes:
1. Top rail unlevel
2. Lift overloaded
3. Concrete anchors loose
Solutions:
1. Replace guide rollers in sets
2. Install new chain sets
3. Replace bearing axles and lubricate bearings
Problems:
1. Bushings and pins Worn out
2. Pulley not turning smoothly
3. Pulley locking up
4. Cable too large for pulley
5. Pulley groove worn or burred
6. Pulley groove squared (no longer rounded)
Causes:
1. Cables worn
2. Cable too large or too small (squaring)
3. Dirt/sediment in bushings and pins
Solutions:
1. Inspect and replace worn axles and sheaves
2. Lubricate cables per OEM specifications
3. Replace equalization cables as sets for proper function
Problems:
1. Leaks of any kind pertaining to lift
2. Cylinder seals blown/leaking
3. Cylinders leaking
4. Tanks cracked
5. Hose pin holes/broken fittings
6. Power unit lowering valve leaking
Causes:
1. Lift kept under pressure for long periods of time
2. Lift not lowering onto locks
3. Extreme weather
4. Power unit fluid not changed
5. Cylinder pitting from fluid contamination
6. Cylinder seals worn
7. Hydraulic system topped off using incorrect fluids
8. Hoses worn/improperly routed or overtightened
9. Fittings loose
Solutions:
1. Re-educate lift operator on proper use of latches
2. Replace worn seals or entire cylinder assembly
3. Flush hydraulic system and replace with proper fluid
4. Repair/replace work fittings and hoses
Problems:
1. Signs of leaking
2. Loads lifted improperly – power unit weakness
3. Lowering valve not holding pressure
4. Motor humming or making noises
5. Switch or breaker bad
Causes:
1. Fluid not changed on a regular basis
2. Unit changed or topped off using improper fluid
3. Lift kept under pressure for long periods of time
4. Lift not lowering onto locks
5. Extreme weather
Solutions:
1. Replace power unit assembly
2. Flush hydraulic system and install proper fluid per OEM specifications
3. Replace faulty breaker or switch assembly
4. Protect system parts from exposure to extreme elements
Problems:
1. Latches not hooked up and operable
2. Air leaks audible
3. Latch not engaging
4. Cables not adjusted/equalized properly
Causes:
1. Springs and other parts missing
2. Cable not hooked up properly
3. Objects (like screwdrivers) used to hold latches open
4. Air cylinders missing/non-functioning
5. Fittings or air lines missing
Solutions:
1. Replace missing latch parts
2. Adjust locking latches to OEM specifications
3. Replace leaks in air supply system for latches
4. Replace and adjust latch release cable
Lift maintenance is critical to the life of the lift. Allpart is available to provide parts and expert advice to help lift operators in setups of all sizes, from small shops to large-scale fleet maintenance operations, ensure their lifts last decades and their staff remains protected.
Allpart specializes in providing parts of high quality for all makes and models of lifts, whether they be discontinued models or new to the market. Allpart’s experienced staff members, each with decades in the automobile servicing business, are experts at quickly diagnosing lift issues and providing dependable, hard-to-find solutions in real time.
Again, if mechanics spot any of the conditions outlined above on a four post lift, schedule service immediately and contact Allpart Supply for the necessary parts for a properly-functioning and secure automotive lift.
Allpart Supply has years of experience helping lift operators find dependable automotive lift solutions in the most expedient, painless way possible. Allpart has all parts for all brands, finding operators the solutions they need.