Inside: Flymo or Bosch Rotak Won’t Start? 4 Cheap Fixes to Check Before You Buy a New Mower. Collaborative post.
Your electric mower won’t start, or it keeps stopping before you’ve finished the lawn. That’s frustrating when the grass needs cutting, but it doesn’t usually mean the mower is finished. On a Flymo (hover or wheeled) or a Bosch Rotak, the cause is often small and cheap to put right, and you can track it down yourself even if you’ve never taken anything apart.
1. Check the power: the RCD, the extension lead and the plug fuse
The power supply is the likely cause if:
• nothing happens at all when you press the button and pull the lever: no hum, no whirr
• the mower stopped mid-mow and won’t start again
• the RCD has tripped, or the lights or sockets in part of the house went off at the same moment
• you’ve run the mower over the extension lead, or left the lead out in the rain
How to check the power
You don’t need a toolbox for these checks, just a spare fuse and a lamp you know works.
1. Check the RCD. An RCD cuts the power in an instant if electricity leaks where it shouldn’t, such as through a cable you’ve just run the mower over. If your RCD is a plug-in adaptor or built into the socket, press its reset button; if it’s in the fuse box, find the switch that has dropped and push it back up. Then press the RCD’s test button. It should cut the power straight away; reset it afterwards. If nothing happens, the RCD won’t cut the power in a real fault either, so replace a plug-in RCD, or ask an electrician to check an RCD in the socket or the fuse box. If RCDs are new to you, read up on what an RCD does and how to test it.
2. Check the socket. Plug the lamp into the same socket. If the lamp stays off, the fault is in the socket or the wiring to it, not the mower.
3. Check the extension lead. Unplug it, unwind it fully from its reel and run it through your hands from end to end. Look for cuts, nicks, flattened patches and bare wire, and for cracks or scorch marks on the plug and socket. Then plug the lead in and plug the lamp into the far end. If the lamp lights, power is getting through the lead. If it stays off and your reel has a reset button, press it: some reels cut out when they get too hot, which is also why you should unwind the lead fully every time you mow. If you find damage, don’t tape it up. Buy a new extension lead made for outdoor use, as electrical safety advice for the garden recommends.
4. Change the plug fuse. A blown fuse usually looks the same as a good fuse, so the quickest check is to fit a new fuse. Unplug the mower. On most moulded plugs the fuse sits in a small carrier between the pins; ease the carrier out with a fingernail or the tip of a small screwdriver. Swap the old fuse for a new fuse with the same rating (look for the rating on the side of the old fuse), push the carrier back in and try the mower again. The extension lead’s plug has a fuse too, so check the fuse in that plug as well. If you’ve never done this before, there’s a guide to checking and changing a plug fuse.
If the mower or the lead got wet, leave them in a dry shed or garage to dry out before you try again. If a new fuse blows or the RCD trips the moment you start the mower, don’t fit a bigger fuse or keep resetting the RCD: there is a fault in the cable or inside the mower. Leave it unplugged, check the cable in fix 2, and if the cable looks sound, take the mower to a repair shop before you use it again.
2. Check the start sequence and the cable
Suspect the start sequence or the cable if:
• the power checks out, but nothing happens when you try to start the mower
• the mower starts for one person in the house and not for another
• the mower cuts out when the cable pulls tight, or as you turn at the end of a row
• the cable has a cut, a nick, a flattened patch or old tape wrapped round it
• the cable hangs loose at the handle instead of looping through its restraint
On Flymo and Bosch mowers you have to use two controls in the right order before the motor starts, so nobody can start the mower by accident.
How to start it properly and check the cable
1. Find the start sequence for your model. It’s in the owner’s manual, and the order changes from model to model. If the paper copy has gone, you can download the manual from the Flymo website or the Bosch website.
2. On a Bosch Rotak, use the two-step start. On most corded Rotaks you press and hold the safety button on the handle, then pull the start lever towards the handle and keep holding the lever.
3. On a Flymo, press the button before you pull the lever. On many Flymo mowers you press the start button on the switch box, then pull the start lever towards the handle and keep holding it. If you pull the lever first, nothing happens: let go of the button and the lever and start again in the right order. The order differs on some models, so check the manual for yours.
4. Unplug the mower and check the mains cable. Run the cable through your hands from the plug to the handle, looking for cuts, nicks, flattened patches and bare wire. Look hardest near the plug and the handle, where the cable bends most. If the cable is damaged, replace it rather than taping it. If the cable unplugs from a connector at the handle, a new cable simply plugs in; if it runs straight into the switch box, a local mower repair shop can fit a new cable.
5. Check the cable restraint. The cable should loop through the restraint, a hook or clip on the handle. Then a tug on the cable pulls on the hook, not on the connection. If the cable doesn’t loop through the restraint, or the restraint is loose or cracked, the connection can pull apart as you mow. Push the two halves of the connector fully together, loop the cable through the restraint the way the manual shows, and tighten or replace a loose or broken restraint.
3. Replace a worn on/off switch in the handle
Once the power, the start sequence and the cable check out, a worn on/off switch in the handle is one of the most common reasons an older Flymo or Bosch Rotak won’t start, and it’s a cheap part, matched to your mower’s model, that you can replace yourself with a screwdriver.
Suspect the switch if:
• the mower only starts if you squeeze the lever extra hard, hold it at an angle or try several times
• the mower cuts in and out while you hold the lever steady
• the button or lever feels loose or sticky, or doesn’t spring back
• you’ve heard a crackle or a pop from the handle, or smelled burning there
• the mower has had years of use
The on/off switch in the handle is one of the parts that most often wears out on an older mower: every start makes the contacts inside the switch spark a little, and over the years they wear until they stop connecting properly. On many Flymo models, a small capacitor sits in the switch box, wired in beside the switch.
How to change the switch
You need a screwdriver that fits the screws on the switch box, and a phone to take photos.
The new switch has to match your mower, so find the model number first. It’s on the rating label, a sticker or small plate on the deck or the motor housing (the cover over the motor). Brush off any dried grass so you can read the label, then photograph the whole label, including the model name and any longer number. If you can’t spot the label, the maker’s help pages show where to find the model number.
Top Deals Online are worth checking first for a replacement switch, because they list each switch by the mower it fits: switches to fit the Flymo Hover Compact, Easi Glide and Glider start at £8.49, and there’s one to fit the Bosch Rotak 32, 320, 40 and 43. Check your model number against their list of mower switches.
If you’d rather not open the switch box yourself, a local mower repair shop can fit the new switch for you. To fit the new switch yourself:
1. Unplug the mower. Never open the switch box with the mower plugged in.
2. Undo the screws on the switch box and keep them in a cup so none go missing. Lift the cover off slowly, so the lever and any springs stay in place.
3. Before you touch a wire, photograph the inside of the switch box from a couple of angles, so you can see which colour wire goes to which terminal (connection point) on the switch.
4. Move the wires across one at a time: take a wire off the old switch and fit it to the matching terminal on the new switch before you move the next wire. That way no wire ends up on the wrong terminal.
5. If your Flymo has a capacitor in the switch box, look at it while the switch box is open. If the capacitor is swollen, cracked or scorched, fit a new capacitor that matches your model, moving its wires across one at a time in the same way.
6. Put the new switch where the old switch sat, check the lever and springs are back in place, and tuck the wires into their channels so the cover can’t pinch them. Refit the cover and all the screws.
7. Plug the mower in through an RCD and run the start sequence. The mower should start first time and keep running while you hold the lever. If the fuse blows or the RCD trips, unplug the mower and check the wiring against your photos.
4. Clear a blocked blade and let a hot motor cool
A blocked blade or a hot motor is the likely cause if:
• the mower hums but the blade doesn’t spin (let go of the lever at once)
• the motor slowed down in long or wet grass, then stopped
• the mower cut out after a long mow and starts again once it has stood for a while
• you heard a clunk or a rattle just before the mower stopped
• grass stopped going into the grass box, or a hover Flymo started dragging on the lawn instead of floating
• you can smell a hot motor or burning grass
When wet grass packs under the deck (the body of the mower over the blade), or a stone or stick jams the blade, the motor heats up quickly, and on many mowers a cut-out switches it off before it burns out.
How to clear the deck safely
Unplug the mower before you touch the blade or open anything. The blade is sharp even when it isn’t turning, so wear thick gardening gloves.
1. Let go of the lever and unplug the mower.
2. Leave the motor to cool. If a cut-out has switched the motor off, the mower won’t start again until the motor has cooled down, so clear the deck while you wait.
3. If your mower has a grass box, take it off and empty it.
4. Tip the mower on its side or turn it over, the way the manual shows, so you can see under the deck.
5. Scrape the packed grass out from under the deck and around the blade, and clear the chute that leads to the grass box. Use a wooden stick or a plastic scraper, not your fingers. Don’t hose the mower down, because water can get into the motor.
6. Pull out any stone, stick or toy caught around the blade.
7. Still wearing gloves, turn the blade slowly by hand. It should turn freely all the way round; if it catches, look again for something trapped. If the blade is bent or badly chipped, fit a new blade before you mow again, because a bent blade makes the mower shake.
8. Turn the mower the right way up, refit the grass box, plug in and try again.
To stop the deck clogging again, mow when the grass is dry and empty the grass box before it’s full. If the lawn has grown long, raise the cutting height and bring the grass down over several cuts, a little lower each time.
If the mower still won’t start after all four fixes, the motor itself may be worn. On many corded mowers the parts that wear in the motor are the carbon brushes, small carbon blocks that carry power to the motor as it turns. A local mower repair shop can tell you whether yours can be replaced and what it would cost before you buy new. If the mower really is finished, keep it out of the household bin: old electrical goods should go for recycling, and your council’s household waste recycling centre can take it.
Common mower questions
Why won’t my Flymo start?
The usual causes are no power reaching the mower (a blown plug fuse, a damaged extension lead or a tripped RCD), pressing the start button and pulling the lever in the wrong order, a damaged cable, a worn switch in the handle, or grass or a stone jamming the blade. Check them in that order, starting with the power.
Where do I find the model number on my mower?
On the rating label, a sticker or small plate on the deck or the motor housing. The label shows the model name and a longer reference number. Photograph the whole label so you have it to hand when you order a replacement switch or ask for a repair quote.
Is it worth repairing an electric lawnmower?
Usually, yes. A blown fuse, a damaged lead or cable, a blocked blade and a worn switch all cost far less to put right than a new mower. The time to weigh it up is when the motor itself is worn: get a repair quote and compare it with the price of a new mower.
How long should an electric lawnmower last?
There’s no fixed lifespan. An electric mower that you brush clean after each mow and keep in a dry shed or garage can last for many years, and you can replace the switch, the blade and the cable as they wear. When the motor itself wears out, get a repair quote before you decide the mower is finished.