Fuel filter housing issues - and how to fix them!

Like any vehicle, a motorhome relies on its engine and associated parts running smoothly for things to go well. One fairly common cause of problems in motorhomes, however, is the fuel filter housing developing a fault - and if it’s not rectified, an issue like this can cause poor performance, starting difficulties or even leave you stranded by the roadside!

Here’s what you need to know about some common fuel filter housing faults, how to spot the signs, and then what you can do to fix them.

What is the fuel filter housing?

The fuel filter housing is made up of three individual components, and it ultimately forms the casing that holds the fuel filter in place within the engine bay. The unit connects the fuel lines and ensures fuel flows properly through the filter, removing dirt, water, and other impurities before it reaches the engine.

While it might seem like a simple part, it does play a vital role in the whole system. If something concerning the housing develops faults, it can disrupt fuel delivery, allow contaminants into the fuel, and cause a whole host of engine issues.

Some of the most common problems that can occur…

Cracks and leaks

Over time, the casing can become brittle, especially with the heat cycles that occur under the bonnet (if it’s situated there). Any cracks or splits can cause fuel leaks, which not only affect the motorhome’s performance but could also become a fire hazard.

Warping or poor seals

If the housing doesn’t seal tightly, air can be drawn into the fuel system. This leads to poor starting, rough idling or even the engine stalling.

Thread damage

The housing is often opened during servicing to replace the filter. If the threads are overtightened or cross-threaded, it can damage the unit, preventing a proper seal.

Blocked drain valve

Many housings include a drain valve for removing water from the diesel. If this valve blocks or fails, water can build up, reducing fuel quality and risking injector damage.

What are the symptoms of a fault?

• Difficulty in starting the engine, especially after it’s been standing still

• A loss of power or hesitation when accelerating

• Visible diesel leaks in the engine bay or on the floor

• A strong smell of fuel around the vehicle

• Warning lights on the dashboard such as the engine management light

If you notice any of these signs, the fuel filter housing could have an issue.

How to fix these issues

Check for leaks and cracks

Inspect the housing carefully, with a torch if needed. Look for any hairline cracks, damp patches or staining that suggests diesel is leaking out.

Replace the seals

Sometimes the issue is as simple as a perished seal. Replacing the rubber O-rings can restore a proper seal - but always use manufacturer-approved parts, though.

Tighten the connections in the vicinity

Make sure all pipes and fittings are properly secured, as any loose clips or connections can allow air to enter the system.

Replace the filter, or the housing itself

In many cases, replacement is the only long-term fix. Luckily, complete fuel filter housings are relatively inexpensive and widely available. You can pick one up for around £60-£100, depending on which one your motorhome needs. All our buyers have them on them when going to purchase motorhomes, as it is such a common problem that we come across!

Preventative care

Avoid over-tightening the housing during filter changes. Use high-quality fuel filters to reduce the strain on the unit, and have your motorhome serviced regularly to catch any potential problems early.

So there we are. Fuel filter housing issues are a well-known weak point in many motorhomes, but they don’t have to spoil your adventures, by any means! By recognising the symptoms early and fitting a new housing if needs be, you can avoid breakdowns and keep your motorhome running smoothly.

Also, regular servicing and careful attention during filter changes goes a long way in preventing problems from arising in the first place.