FORKLIFT CHAIN ADJUSTMENT
Chain adjustments are important
for the following reasons:
• Equal loading of chains
• Proper sequencing of mast
• Prevent over-stretching of chains
• Prevent chains from jumping off sheaves if they are too loose
1. With mast in its fully collapsed and vertical position, the height from the floor to the top of the fork line (tip) should be 2.60 inches.
2. Chain should also be adjusted to provide equal loading of chains. Adjustment of lift chains is done by loosening or tightening a retaining nut on the threaded chain anchor.
After making adjustments, tighten the jam nut. Also make sure that the chain anchors are not twisted with respect to the chain links.
LIFT CHAIN LUBRICATION
The most important consideration
in field maintenance of lift chains is lubrication. Hard
working, heavily loaded chains cannot be expected to give
satisfactory wear life without scheduled periodic relubrication.
Like all bearing surfaces, the precision manufactured,
hardened-steel joints in lift chain require a film of oil
between mating parts to prevent rapid wear. Oil must penetrate
the chain joint to prevent wear. Applying oil to external
surfaces will prevent rust, but oil must flow into the live
bearing surfaces for maximum wear life. Frequency of lubrication
will vary with operating conditions and environment. The best
estimate of lube period is 250 hours. Trucks parked outdoors or
trucks in extremely severe service may require more frequent
relube to maintain an oil film on all chain surfaces.
a. Wipe off the old oil with a clean cloth and blow out the remaining dirt with compressed air. Wear eye protection.
b. With a clean brush, apply EP-140 extreme pressure lubricant, or heavy motor oil (40W). Your local PREMIER Parts dealer can provide aerosol Grease Gun In A Can (part number 1500369-04) for chain lubrication.
LIFT CHAIN REPLACEMENT
Order replacement chain from your
authorized Premier Parts dealer by part number.
Replace chains as a pair. It will be virtually impossible to maintain uniform loading between the strands if a new chain is put into service opposite an old chain. The joints in the old chain will have worn through the hardest layer of the case-hardened pin. Therefore, the wear rate on the old chain will be greater than that on the new chain, greatly complicating the problem of maintaining equal chain tension.
The new chain will wear more slowly, causing it to bear the major portion of the load - resulting in premature wear and fatigue failure.
Do not steam clean or degrease new chains. The manufacturer’s grease is effective in reducing wear and corrosion. If the original factory lube is dried out or wiped off, soak the new chain in heavy engine oil for at least 1/2 hour prior to installing on truck.
After the old chains have been stripped from the mast, very carefully inspect chain anchors and sheaves. Broken, cracked or worn anchors must be replaced. Replace worn sheaves and check sheave bearings for wear.
Do not paint new replacement chain before or after it has been installed. Paint will help prevent corrosion, but will prevent oil from reaching the pin surface for good joint lubrication. Install the new chains, using new anchor pins. Old pins may contain invisible fatigue cracks that could lead to pin failure. After chains have been connected to the anchors, adjust chain tension.
1. Use lengths of factory
assembled chain. Do not build lengths from individual
2. Do not attempt to rework damaged chains by replacing only the components obviously faulty. The entire chain may be compromised and should be discarded.
3. Never electroplate assembled leaf chain or its components. Plating will result in failure from hydrogen embrittlement. Plated chains are assembled from modified, individually plated components.
4. Welding should not be performed on any chain or component. Welding spatter should never be allowed to come in contact with chain or components.
5. Leaf chain is manufactured exclusively from heat treated steels and therefore must not be annealed. If heating a chain with a cutting torch is absolutely necessary for removal, the chain should not be reused.
6. The practice of joining chain lengths is not recommended, and chains from different manufacturers should not be placed together within the same application.
7. The Minimum Ultimate Strength of a chain means the minimum load at which it will break when subjected to a destructive tensile test. It does not mean working load.