RV Sewer Hose Leaking: What Causes It and How to Fix It

A leaking RV sewer hose is one of those problems that announces itself immediately. If you are dealing with a drip, a loose connection, or a crack along the hose body, the fix is usually straightforward once you know which part is actually failing. This guide walks through the four most common causes and what to do about each one.

The four most common causes

1. A worn or missing fitting gasket

The most frequent source of leaks is not the hose itself; it is the connection point. The elbow fitting at the dump station end relies on a rubber gasket to create a sealed connection. When that gasket dries out, cracks, or gets lost during a previous dump session, the fitting will leak around the rim no matter how firmly you press it in.

Check the elbow fitting first. If the gasket is visibly cracked, flattened, or missing entirely, replace it before replacing the whole hose. Camco RhinoFLEX replacement fittings and elbow adapters are stocked at The Trailer Guys, including the RhinoFLEX bayonet fitting and the 4-in-1 elbow with a built-in gasket for an odour-tight connection.

2. A loose or unlocked bayonet connection

The bayonet fitting on the trailer end of the hose locks into the outlet with a twist. If it is not fully seated and rotated to the locked position, it will leak under flow. This is common after a rushed hookup or when the outlet has worn threads that no longer hold the fitting firmly.

Disconnect, reseat, and lock the fitting with a deliberate twist. If the outlet threads are stripped or the bayonet no longer clicks into place, the RV drain and waste valves section has replacement outlet hardware.

3. A cracked or punctured hose body

Sewer hoses degrade with use. The vinyl and polypropylene materials that make up standard and heavy-duty hoses become brittle over multiple seasons, especially when stored compressed in direct sunlight or left exposed through Atlantic Canada winters. Small cracks along the accordion folds are the most common failure point and will not seal with tape or patch products.

A cracked hose needs to be replaced. There is no reliable field repair for a compromised hose body. The RV sewer hoses and accessories collection carries Camco RhinoFLEX kits in 15-foot and 20-foot lengths, Duraflex Gator hoses in 15, 20, and 30-foot lengths, and standard Camco heavy-duty hoses starting at C$33.99. The Duraflex Gator's 24 mil polypropylene construction handles the repeated freeze-thaw cycles Atlantic Canada trailers go through better than thin vinyl alternatives.

4. Hose drooping between trailer and dump inlet

A hose that sags in the middle does not leak in the traditional sense, but pooling waste in the low section creates backpressure at both connections and puts stress on the fittings. Over time, this issue causes joint failures that look like leaks but are actually caused by the unsupported weight of the hose.

The fix is a hose support. Camco's 20-foot Sidewinder sewer hose support holds up to 15 feet of hose off the ground on an elevated cradle. It collapses for storage and eliminates the sagging problem entirely.

When to replace vs. when to repair

Replace the hose if the body is cracked, kinked permanently, or older than three to four seasons of regular use. Repair the connection if the hose body is intact but the fitting, gasket, or elbow adapter is the failure point. Fittings are inexpensive and stocked individually — there is no reason to replace a good hose because of a failed $5 gasket.

If you are unsure whether the hose or the connection is the source, fill the hose with water at the trailer end while it is disconnected from the dump station and watch where the drip appears. That test takes 30 seconds and tells you exactly which part to replace.

What to have on hand before camping season

A spare bayonet fitting, an extra elbow adapter, and a replacement hose clamp weigh next to nothing and store in the same bumper compartment as the hose itself. Having them on hand means a fitting failure at a campsite does not become a trip-ending problem.

The full range of RV sanitation parts, hoses, fittings, elbows, adapters, clamps, and hose supports is stocked at The Trailer Guys at 745 Route 133, Boudreau Ouest, New Brunswick, with Canada-wide shipping available. Call or text the team if you want help matching a fitting to your specific trailer outlet before ordering.

Frequently asked questions

Can I repair a crack in my RV sewer hose with tape?

No. The accordion fold construction of sewer hoses flexes every time the hose is extended or compressed, and tape will not hold through that movement. A cracked hose body needs to be replaced.

Why does my sewer hose leak only when I open the black tank valve?

The sudden surge of flow when the black tank valve opens puts more pressure on connections than the grey tank does. If the leak only happens at that point, the bayonet fitting or elbow gasket is the likely culprit — the connection is holding at low flow but failing under higher pressure.

How long should an RV sewer hose last?

A quality hose used seasonally and stored properly should last three to five seasons. Hoses stored compressed in direct sunlight or left outdoors through winter will degrade faster. Inspect the accordion folds for micro-cracks at the start of every season.

Where can I buy RV sewer hose fittings in Atlantic Canada?

The Trailer Guys carry Camco RhinoFLEX and Duraflex hoses, fittings, elbow adapters, clamps, and hose supports at 745 Route 133, Boudreau Ouest, New Brunswick. Everything ships across Canada. Browse the full RV sewer hose collection or contact the team by phone or text for part matching help.