Kyotechs' seal kit catalogue is documented kit by kit — each listing names the kit number, the cylinder it serves and the machine it fits, from the Volvo EC240 excavator bucket cylinder kit (14589133) to a run of wheel-loader cylinder kits. That structure is not bureaucratic fussiness: it reflects how seal kits actually work. A kit is a matched set of seals, wipers, wear rings and O-rings for one specific cylinder. This guide explains how to identify yours.
Step 1: Identify the Cylinder, Not Just the Machine
"Seal kit for a Volvo EC240" is not an orderable description. The EC240's boom, arm and bucket cylinders are three different cylinders with three different kits. The orderable facts are the machine model, the cylinder's position, and above all the cylinder or kit number — stamped on the barrel, cast on the gland, or listed against the cylinder in the machine's parts book. Quote all three and the match is checkable before the kit ships.
Step 2: If the Number Is Gone, Measure
Numbers corrode. When they do, the measurements that identify a kit are the bore diameter, the rod diameter, and the seal groove dimensions taken from the old seals and the gland. Measure with calipers, photograph the old seals laid out in order, and record which cylinder they came from. A supplier working from bore, rod and groove figures can usually identify the kit; a supplier working from a photograph of a leaking cylinder cannot.
Step 3: Match the Kit to the Cylinder's Job
The documented listings show how specific kits are: a boom lift cylinder kit, a bucket tilt cylinder kit and a steering cylinder kit for Volvo wheel loaders are separate listings with separate numbers, because cylinder dimensions and seal arrangements follow the job the cylinder does. Steering and tilt cylinders on loaders, boom and bucket cylinders on excavators — same principle. Never assume two cylinders on one machine share a kit, and never let a seller substitute a "similar" kit without a number-level match.
Step 4: Avoid the Four Common Mistakes
- Ordering by machine model alone — the mistake this guide exists to prevent; position and number decide.
- Reusing wear rings and old O-rings — a kit is a set; partial replacement leaves the wear that caused the leak.
- Fitting new seals into a damaged cylinder — a scored rod or worn bore destroys new seals quickly. Inspect the chrome and the barrel first; if they are damaged, the job is a cylinder repair, not a reseal.
- Contamination during assembly — seals fitted in a dirty environment start leaking early. Clean components, lubricated seals and correct orientation are not optional refinements.
Step 5: Know When a Kit Will Not Fix It
A kit cures seal wear. It does not cure a bent or scored rod, a worn bore, a cracked gland or a cylinder that drifts because its piston seal seat is damaged. Drift under load with healthy-looking externals usually is seal leakage and responds to a kit; oil weeping at the gland with visible rod scoring does not. If the inspection points past seals, the hydraulic cylinder page covers the replacement route, and the seal kits page holds the documented kit index when a kit is the answer.
To order, send the kit or cylinder number, machine model and cylinder position via the contact page — the reply confirms the documented listing that matches before anything is packed.
Worked Example: Three Kits, One Machine
Consider a Volvo EC240 whose bucket cylinder weeps at the gland and drifts slowly under a held load. The machine model is known; the work starts there. The parts book entry for the EC240's bucket cylinder leads to the documented kit 14589133 — a bucket cylinder kit, for this machine. Note what the identification did not do: it did not borrow the boom cylinder's kit, although both cylinders sit on the same machine and look similar on the bench, and it did not borrow any of the wheel-loader kits in the same catalogue extract, although several carry Volvo numbers in the same series. If this machine's arm cylinder starts drifting next season, that is a new identification and a different kit — the discipline repeats, it does not carry over.
Fitting Day: The Habits That Decide Whether the Kit Works
Most reseal failures are fitting failures. The bench should be cleaner than the machine: seals pick up grit from a dirty bench and carry it into the bore. Lay the old seals out in removal order and photograph them before anything is discarded — the layout is the assembly diagram when memory fades. Lubricate every seal with the system's own hydraulic oil, never grease that the system cannot dissolve. Warm stiff seals in warm water rather than forcing them cold over sharp edges. Replace every wear ring and O-ring in the kit, even the ones that look serviceable; their wear is why the kit exists. After assembly, work the cylinder through its full stroke unloaded before it earns its keep, and check the gland after the first loaded hour. Finally, record the kit number and the date in the machine's file — the next reseal, years from now, starts from that record instead of from a corroded number and a measuring session.
The Seal Kit and the Bigger Repair Picture
A reseal also functions as an inspection opportunity. With the cylinder open, the rod chrome, bore surface, piston and gland tell the machine's hydraulic story: scoring patterns reveal contamination, bent-rod evidence reveals side loading, and the state of the old seals reveals the oil's temperature history. Shops that treat the open cylinder as evidence catch the neighbouring failures — the pump shedding metal, the valve passing debris — before they become the next breakdown. That is the same philosophy as Kyotechs' repair programmes, where components are opened, inspected and tested rather than merely exchanged: the part in hand is information, and the guide's last advice is to read it before it goes back together.
If the machine in front of you is not the documented one, none of the worked examples transfer by resemblance — but the method transfers completely. Number first, dimensions second, condition third, and the catalogue's own words over anyone's summary of them, including this guide's: use it to ask better questions of the record, and let the record answer.
And keep the old kit until the new one is proven under load. The removed seals are the only physical record of how the cylinder was failing; if the new kit weeps in its first week, the comparison between old and new — wear faces, hardness, damage pattern — is what separates a fitting error from a bore problem, and it cannot be made once the old seals are in the bin.