Something Doesn't Smell Right: What Your Westwood Is Trying to Tell You

Smell is one of the most underrated diagnostic tools a mower owner has. Most of us are reasonably good at noticing when something doesn't look or sound right with a machine, but we're less used to paying attention to what it smells like. In practice, unusual smells from a running mower can be among the earliest and most useful warnings that something needs attention, often before any visible or audible symptom has appeared.

If something smells off during or after a mowing session, here's a plain-English guide to what the most common smells usually mean and what to do about them.

Burning Rubber

A smell of burning rubber is one of the more common unusual smells from a lawn tractor, and it almost always points to one of the drive belts. Westwood tractors use belts to transfer power to the cutting deck and the transmission, and when a belt slips, rubs against something it shouldn't, or starts to break down, it produces a distinctive hot rubber smell.

Belt slipping can happen for several reasons. The belt may have stretched slightly and lost tension over time, a pulley may be misaligned, or there may be a buildup of grass or debris causing the belt to rub. In some cases, the smell appears when the machine is under load on a slope or in thick grass, which is often the first sign that belt tension has dropped.

If you notice a burning rubber smell, it's worth switching off, letting things cool down, and having a look at the belt condition before continuing. A belt that's slipping will eventually fail, and catching it early means a straightforward replacement rather than a more involved repair.

Hot Oil

A smell of hot or burning oil usually means oil has found its way onto a hot surface somewhere on the engine. This is most often the result of a minor leak from a gasket or seal, where a small amount of oil is dripping onto the exhaust or the engine block and burning off on contact.

The first thing to do is check the oil level. If it's dropping between uses, that's a sign there is indeed a leak somewhere rather than just residual oil burning off from a previous spill. Small oil leaks are very common on engines that have been in service for several years, and in many cases they're straightforward to address once the source has been identified.

If the oil smell is accompanied by visible smoke from the engine area, it's worth stopping the machine promptly and having it looked at before continuing to use it.

Fuel Smell

A strong smell of petrol during or after mowing can have a few different causes. A small amount of fuel smell when starting a cold engine is fairly normal and usually dissipates quickly. A persistent fuel smell during operation is a different matter.

The most common causes are a loose or deteriorated fuel cap, a fuel line that has developed a small weep, or a carburettor that isn't sealing properly. Any situation where raw fuel is escaping from the fuel system rather than being burned in the engine is worth taking seriously, both because it affects performance and because fuel is, of course, flammable.

If the fuel smell is strong and persistent, it's sensible to stop mowing, allow the machine to cool, and investigate or have the fuel system checked before using it again.

Exhaust Smell Changes

Most engines have a characteristic exhaust smell that owners become familiar with over time, and a change in that smell can be informative. A sweet or slightly sickly smell from the exhaust can indicate a coolant issue on engines that are liquid-cooled. A heavy, acrid smell often accompanies burning oil, which can point to worn piston rings or valve seals allowing oil to enter the combustion chamber.

A sudden change in exhaust smell, particularly if accompanied by a change in smoke colour or engine behaviour, is worth noting and investigating. Blue or grey smoke alongside a strong oil smell usually means oil is being burned in the engine, while black smoke and a rich, heavy exhaust smell often points to a fuelling problem.

A General Rule

With any unusual smell, the sensible approach is the same: take note of when it appears, whether it's constant or only under load, and whether anything else has changed alongside it. That information is genuinely useful to anyone who then looks at the machine, and it often makes the difference between a quick diagnosis and a lengthy investigation.

Your Westwood is a robust and reliable machine, but like anything mechanical, it benefits from an attentive owner. Trusting your nose is a perfectly valid part of keeping it in good shape.