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978-368-3325
Compactors & Balers · Hydraulic · H-14

Why Is Oil Running Down the Cylinder Rod?

Oil running down the rod means the rod seal in the cylinder gland has failed. The cylinder is pushing oil past that seal on every stroke. It will not reseal itself and it gets worse — the fix is a reseal or a replacement cylinder, and which one depends on the condition of the rod chrome.
Get This Cylinder Quoted — 978-368-3325
All Hydraulic Symptoms
Tier 1 to look at it. Tier 3 to open it. Serving New England from Clinton, MA.
Step One

Confirm It in One Cycle

You do not need tools for this and you do not need to open anything. It takes about two minutes and it tells a technician more than a phone description ever will.

Wipe the rod clean.

Rag along the full exposed length of chrome, right up to the gland face. Get it dry.

Run one full cycle.

Extend and retract once, normally, with whatever is in the chamber.

Look again.

A wet film that has returned along the rod after a single stroke is a failed rod seal. That is the answer.

Check where it sits.

Oil on the rod itself points at the seal. Oil pooling at the gland face with a dry rod is usually a loose gland or a failed wiper — related, but a different repair.

Photograph it.

One shot of the whole cylinder in place, one close on the rod. Send it with the call.

Why this test matters more than it looks

A compactor cylinder is filthy by default. Old oil, road salt and wet-waste residue coat everything, so “there’s oil on it” describes every compactor in New England. Wiping it and watching one cycle is what separates an active leak from ten years of accumulated grime — and it is the difference between a diagnosis and a guess.
Why It Gets Worse

What It Costs to Leave It

A weeping rod seal is not an emergency the day it starts. It is a clock, and the thing it is counting down is the price of the repair.

Now

Rod chrome still smooth, bore still in spec. This is a seal kit and a reseal — the cheapest version of this repair that exists.

A few months on

The wiper is no longer wiping, so every retract stroke drags grit past it. The rod starts to score and the new seal’s life gets shorter.

A season on

Scored rod, worn bore, contaminated oil working its way back through the pump. Now it is a replacement cylinder and possibly a pump.

The other cost

Hydraulic oil on a slab that drains to a storm inlet is an environmental problem before it is a mechanical one. On a self-contained unit at a retail or residential site, a visible oil track is also the thing a property manager photographs and forwards. It tends to become urgent for reasons that have nothing to do with the cylinder.
The Decision

Reseal or Replace?

This is the question every quote comes down to, and the answer is not a judgment call — it is a measurement.

Reseal it

Rod chrome intact — no pitting, no flaking, no rust streaks — and the barrel bore measures within spec.

Pressure wash, disassemble, inspect, clean the seal surfaces, measure and order seals, reassemble, then test for operation, leaks and bypass before it goes back.

Replace it

Rod pitted, flaking or rust-streaked, or the bore has opened up past spec.
A new seal running on scored chrome is cut apart by the rod within weeks. When the OEM cylinder is gone or on long lead time, we build a domestic replacement to the original dimensions.

Why we will sometimes talk you out of a reseal

A reseal is the smaller invoice, which makes it the easier sale. But a reseal on a bad rod means paying for the teardown twice and losing the machine twice. If the rod is pitted we will say so, and we would rather lose the reseal than have the same cylinder back in the shop in six weeks.
Before You Call

What We Need to Quote It

You do not need all of this — the make and model plus photos is usually enough to get started. But the more of it you have, the closer the first number is to the final one.
  • Bore — Inside diameter of the barrel. Stamped on many data plates; otherwise we measure it.
  • Stroke — Fully extended length minus fully retracted length.
  • Rod diameter — Across the chrome, measured with calipers if you have them.
  • Mount type — Clevis, cross-tube, trunnion or flange — and the pin diameter.
  • Pin-to-pin retracted — Center of one mounting pin to center of the other, ram fully in.
  • Ports — Size, thread type, and whether they face the same direction or opposite.
  • Machine make and model — Off the data plate. It often tells us the cylinder before you measure anything.
  • Photos — The whole cylinder in place, both mounting ends, and a close shot of the rod.

If you can't get the measurements

Don’t climb on the machine to get them. Send the make, the model and the photos, and we will take the dimensions when the cylinder is out — or bring a replacement with us if we already know that machine.
Safety

Where Your Checking Stops

Tier 1 · Site check

Wiping the rod, running a normal cycle, looking, and taking photos. Nothing opens. No covers, no guards, no fittings.

Tier 3 · Service technician

Removing the cylinder, opening a line, or touching the gland. A compactor parked with the ram out holds pressure with the power off and locked out.

Do not crack a fitting to check for pressure

Stored hydraulic energy is the hazard that makes this Tier 3 no matter how simple the repair looks. Loosening a fitting “to see if there’s still pressure in it” is how people get injection injuries — which do not look serious for the first hour and are a surgical emergency. Pressure gets relieved deliberately and confirmed at the gauge.
Applies To

Compactors and Balers Both

This fault lives in the power unit, so it behaves the same on a stationary compactor and on a vertical baler. One difference is worth naming.

On a baler

Identical fault on the platen cylinder. On a vertical baler the rod is usually easier to see and gets wiped less often, so a weep can run for months before anyone mentions it.
Questions We Get

Rod Leaks, Answered

Can I just tighten the gland nut to stop it?
No. On most compactor cylinders the gland is threaded to a stop and there is no adjustment left to take up. Tightening a gland that is already seated does nothing for a worn seal and can distort the gland bore. If the gland is visibly backed out, that is a different fault and it needs to come apart to find out why.
A weeping rod is not an emergency the day it starts. What it is is a clock. Every retract stroke drags outside contamination past a wiper that is no longer wiping, and that contamination is what scores the rod. A rod caught while it is still smooth is a seal kit. The same rod six months later is usually a new cylinder.
Not necessarily. Oil on the ground can come from the rod gland, a hose or fitting, the pump shaft seal, the valve body, or a cracked weld on the reservoir. Wiping the rod and watching one cycle is what separates a rod-seal leak from everything else.
Both, depending on what the rod measures. If the chrome is intact and the bore is within spec, a reseal is the cheaper and faster answer. If the rod is pitted or flaking, a new seal on that rod fails again in weeks, and a replacement cylinder is the honest recommendation — built domestically to the original dimensions when the OEM part is no longer available.
Get It Running

Show Us the Problem. We'll Build the Fix.

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978-368-3325

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T&T Weber Hydraulic Inc.
184 Stone St, Unit 5
Clinton, MA 01510

Where we go

Onsite compactor and baler service throughout New England — Massachusetts, Connecticut, Rhode Island, New Hampshire, Vermont and Maine. Cylinder reseal and replacement, domestic replacement cylinders, hydraulic, electrical and controls, and full mechanical repair.