説明
A steering pump failure on a large wheel loader does not look like a hydraulic failure at first. It looks like a machine that is heavy to steer at idle and normal once the engine speed rises, which most operators report as a steering problem rather than a hydraulic one. That is why these pumps get replaced after a valve diagnosis and the fault remains.
適合性と根拠
Komatsu WA600-6 wheel loader and WD600-6. Dealer surplus inventory records describe the part with the steering pump designation, which is the strongest evidence available; Komatsu’s online parts catalogue does not return a page we can cite for this number, so the item name is dealer-established rather than manufacturer-confirmed. Trade listings that call it a fan pump are not supported by anything we could check.
How a steering pump fails
- Loss of flow at low engine speed. The steering feels heavy at idle and improves with rpm. That is internal wear, not a relief valve.
- Contamination scoring the sliding surfaces. Large loaders circulate a lot of oil through a steering circuit that is often the last thing anyone filters.
- Case drain back-pressure. Finishes the shaft seal, and the leak is then blamed on a bad pump.
- Cavitation from a restricted suction line. Noise plus a slowly fading steer.
Before ordering, measure steering system pressure at idle and at rated rpm and compare against the machine specification. Our WA380-6 steering pump page および ポンプ購入者および仕様ガイド cover how to do that comparison, and シールキットのリビルドチェックリスト explains what a rebuild should cover if you would rather repair than replace.
取付け
Match shaft spline, pilot, flange, port positions and the control or orifice arrangement against the removed pump; steering pumps on these loaders are often specified by build option, so the serial prefix matters. Prime with clean oil before cranking, change the return filter element, and keep the case drain unrestricted to tank. Target cleanliness around ISO 4406 18/16/13.
ご注文
Minimum order one piece. Three to six month warranty on new aftermarket units as stated on your proforma invoice. Bench checked and photographed against your order before the wooden case closes, delivery 5 to 8 working days from payment subject to stock. the range sits under コマツ油圧ポンプ.
