In October 2026, the HNYT after-sales team helped a mining customer solve a conveyor problem on a ZWY60 crawler mucking loader. The operator reported that the belt had slowed down. The bucket was still digging plenty of ore, but the conveyor could not carry it away fast enough, so rock piled up on the belt and output dropped. After a series of checks, the fault was traced to the hydraulic pump. Once a new pump was fitted, the belt returned to its normal speed and the machine’s loading rate improved noticeably.

The Machine at a Glance

What the Customer Reported

A mucking loader works as a chain: the bucket rakes broken rock from the face and drops it onto the conveyor, and the conveyor carries it to the truck or mine car behind the machine. Both halves have to keep pace. On this ZWY60 the digging side was working normally. The problem was on the conveying side: the belt ran slower than usual, so ore arrived faster than it could be carried away. Rock built up on the belt, the operator had to pause between bucket strokes to let it clear, and each truck took longer to fill.

Because the bucket and the crawler tracks still moved as usual, the machine looked healthy at first glance. A belt that slows down gradually is easy to accept as normal until the drop in output becomes obvious.

How the Fault Was Traced

A slow belt can have several causes, so the checks started with the simple ones. The team looked at belt tension and whether the belt was slipping on the drive roller, and checked the tail roller and the underside of the belt for jammed rock. They then moved to the hydraulic side: oil level and condition, the filters, any leaks, and how the conveyor’s hydraulic motor responded under load. With the mechanical causes ruled out, the evidence pointed to the hydraulic pump.

On this machine the conveyor is driven by a hydraulic motor, and the pump supplies the oil that turns it. As a pump wears, more oil leaks back inside it, so it delivers less flow at working pressure. The motor turns more slowly, and the effect is worst when the belt is fully loaded, which is exactly when the speed matters. This kind of wear builds up over time, and dirty oil speeds it up.

Back to Normal Speed

After the pump was replaced, the conveyor returned to its normal speed. The belt now clears ore as fast as the bucket loads it, so rock no longer piles up and the operator can dig continuously. The customer reported a clear improvement in loading efficiency. The photos in this article are taken from the customer’s video of the machine working after the repair.

Keeping the Conveyor up to Speed

Most conveyor slowdowns can be caught early. Our service engineers recommend a few routine checks for crawler and wheel mucking loaders:

• Hydraulic oil:check the level every shift and replace the oil if it is dark, milky or contaminated with fines.
• Filters:change them on schedule. A blocked filter starves the pump and shortens its life.
• Belt speed under load:if the belt slows when loaded but runs normally when empty, check the pump and the hydraulic motor before the problem gets worse.
• Belt and rollers:keep the tension even on both sides and clear rock from the tail roller and the intake.
• Oversize rock:break large boulders before loading. They overload the conveyor and the hydraulic system.

For a fuller step-by-step check list, see our guide to conveyor belt troubleshooting.

Related Products and Information

• ZWY60 electric crawler mucking loader: full specifications
• Chargeuses à chenilles: all models
• Mining muck loader conveyor belt troubleshooting: why the belt stops or runs slowly
• Why a mining muck loader conveyor belt does not move or runs slowly
• Underground mucking loader: how to choose the right machine

Need Help with a Mucking Loader?

If your mucking loader’s conveyor is slowing down, send us the model, a description of the problem and a short video, and our engineers will help you find the cause. If you are choosing a machine for a new project, send your tunnel width and height, rock type, gradient and required output per shift, and we will recommend a configuration with a quotation.