Mobile Tyre Valve Replacement in London

What's included

• The leak traced with a soapy-water test, so we fix the valve only when the valve is the fault
• A loose or dirty valve core tightened or swapped where that alone stops the leak
• New rubber snap-in valve, or a metal clamp-in valve where the wheel needs one
• High-pressure valves for vans whose tyres run above a standard car valve’s rating
• TPMS sensor valves resealed with a fresh service kit: nut, grommets, core and cap
• Tyre bead broken on the van’s equipment, then the wheel rebalanced before it goes back on
• Pressures set to the maker’s figure and the new valve re-tested for bubbles
• Card or contactless on site, with the cost quoted on the phone before anyone sets off

Why choose Fast Tyre for tyre valve replacement

A tyre that drifts down every few days with nothing in the tread is very often a valve, and the usual answer at a garage is to book in, leave the car and wait. We bring the tyre machine, balancer and valves to wherever the car is parked, find where the air is actually escaping, and only replace what has failed. If the tyre itself is fine you keep it. If something else is leaking, such as the bead seat on a corroded alloy, we show you and tell you straight. Valve jobs at night, at weekends and on bank holidays cost the same as a Tuesday morning.

How we replace a tyre valve at your car

A valve stem passes through the rim from the inside, so it cannot be swapped with the tyre fully seated. The whole job is done beside the car:

• Find the leak first. With the tyre at pressure we brush soapy water over the valve, the core, the bead and the tread. A steady stream of bubbles shows exactly where the air is going, so nothing gets replaced on a guess.
• Try the simple fix. If the bubbles come from the centre of the valve, the core may just be loose or dirty. A core tool and, where needed, a new core can cure it in minutes without touching the tyre.
• Renew the valve. If the stem itself is cracked, split or corroded, the tyre is deflated and the bead broken so the old valve comes out and a new one goes in, of the right type and rating for the wheel.
• Seat, balance, re-test. The tyre is reseated and inflated, the wheel balanced on our van, pressures set to the maker’s figure and the new valve checked again with soapy water before the wheel goes back on.

Signs of a leaking tyre valve

The giveaway is a tyre that loses pressure slowly, over days rather than minutes, with no nail, screw or cut you can find. Other signs are worth knowing:

• A faint hiss when you flex the valve. Rubber stems perish at the base where they meet the rim. Bending the stem gently to one side opens any crack and you may hear or feel air.
• Visible cracking or a stem that leans. Fine splits around the base, or a valve that no longer stands straight, means the rubber has hardened.
• Green or white crust on a metal valve. Corrosion at the nut or seal of a clamp-in or TPMS valve is a common leak point, especially after winters of road salt.
• A missing cap. The cap is a second seal and keeps grit out of the core. A core clogged with dirt can stick slightly open.
• The pressure light keeps coming back on a car with tyre pressure monitoring, always on the same wheel. Our guide to the tyre pressure warning light explains what the different light patterns mean.

To check it yourself, mix washing-up liquid with water, brush or spray it over the valve with the cap off, and watch for a minute. Growing bubbles mean a leak. If the valve stays dry but the tyre still goes down, the cause is elsewhere: our slow puncture guide goes through the other usual suspects.

Rubber snap-in, metal clamp-in or TPMS: which valve your wheel needs

Most cars use a rubber snap-in valve, pulled through the rim hole so the rubber body forms the seal. The common TR413 type is rated by its maker for 4.5 bar and speeds up to 210 km/h, which suits ordinary car tyres. Above that, or where the wheel is designed for it, a metal clamp-in valve is bolted to the rim with a sealing washer and nut. Van tyres often run higher pressures than a car’s, so they take a high-pressure snap-in or a clamp-in rated for the load; fitting a standard car valve to a heavily loaded van is a leak waiting to happen. See our van tyre fitting page for the rest of what we do on commercial vehicles.

On a car with direct pressure monitoring, the valve is the stem of a TPMS sensor that sits inside the wheel. These are mostly aluminium, and the seals are renewed with a service kit rather than replacing the sensor: a new nut, grommets, a nickel-plated core and a cap. A brass core in an aluminium stem corrodes, which is why we never mix them. If the sensor itself has failed or its battery has run down, that is a TPMS sensor replacement instead. For a fuller comparison of the three types, read tyre valves explained.

Can you just replace a tyre valve, or do I need a new tyre?

You can just replace the valve. A leaking valve does not damage the tyre, so a sound tyre with good tread stays on the car and only the valve is changed. The catch is the time the tyre has spent soft: driving on a tyre well below pressure flexes and heats the sidewall, and that can leave damage inside the tyre that you cannot see from outside. With the bead broken we look at the inner sidewall as part of the job. If it shows a band of rubbing or crumbling, we tell you before going further rather than refitting a tyre that is no longer safe.

It works the other way too. When we fit a new tyre we check the old valve while it is exposed, and if it has perished a new one goes in with the tyre, because it will be hidden for the life of that tyre. That is part of the quote for our mobile tyre fitting, so a fresh tyre does not have to come off again later for a tired valve.

How to fix a leaking tyre valve until we get there

If the core is the leak, a cheap core tool from a motor factor will let you nip it up a quarter turn, and fitting the cap firmly stops a small weep. That is as far as a roadside fix goes. A cracked stem cannot be sealed from the outside, and puncture sealant squirted through the valve can clog a TPMS sensor and leave a mess we have to clean off the rim before a valve will seal. Pump the tyre to its normal pressure, keep journeys short, and check it each time you use the car.

A valve that has snapped off after hitting a kerb, or a tyre that is flat on the wheel, is a different matter: do not drive on it. Leave the car where it is safely parked and call us; it is the same response as our emergency tyre call-out, and the valve goes in where the car stands. On a motorway hard shoulder or slip road, call 999 or National Highways on 0300 123 5000 first. We do not work on a live carriageway, but we fit once the car has been moved off the motorway.

Tyre valve replacement near me

Wherever you are reading this in London, from Enfield to Ealing and Hampstead to Harrow, a van can reach you, and the same goes for Hertfordshire, Buckinghamshire, Bedfordshire and the other counties around the capital. We work from our North London base and a fitter typically reaches you within 30 to 60 minutes. Kerbside outside your house, a residents’ bay, a workplace car park or a supermarket car park are all fine, as long as there is room to work safely beside the wheel. If a nail turns out to be the real culprit we can carry out a puncture repair on the same visit, and if you are not sure what is wrong at all, start with our tyre repair near me page.

Tyre Valve Replacement, frequently asked questions