How to Set Up and Run a Greengear LPG Generator Safely (2026)

Last updated: July 2026

In 30 seconds:

• Greengear LPG generators ship with no oil in the engine — fill before the first start or the oil sensor blocks it
• Remove the transportation bolt before starting. Skipping it can wreck the engine mounts
• Propane only, on a firm level base, outdoors, at least 1 metre from anything
• Leak-test every cylinder connection with soapy water before you start the engine
• Models run from £649 (3 kW) to £1,249 (7 kW) — setup is the same across the range

Not sure which size you need? Try our LPG generator sizing guide and calculator. It takes 2 minutes and saves you buying the wrong size.

Greengear generators are the only dedicated, purpose-built LPG generators sold in the UK retail market. They’re widely regarded as the standard choice for traders who want a propane-only setup with no petrol to store. This guide walks you through the full setup — unboxing to shutdown — in 7 steps, using the official Greengear manual plus what we’ve learned running these units at real pitches.

Why “dedicated LPG” matters. A Greengear isn’t a petrol engine with a conversion kit bolted on. It’s factory-built for propane combustion, using the ENERKIT carburettor system engineered with parent company Cavagna Group. Cleaner burn, quieter running, and one fuel on the trailer instead of two.

The honest summary. The biggest mistake new owners make is trying to start the unit straight out of the box. It arrives dry — no oil — and with a transport bolt locking the engine mount. Ten minutes of prep saves you a dead engine and a warranty argument.

What You’ll Need

• Engine oil: SAE 10W-30 or 10W-40, 4-stroke (API SE or higher). 0.6 L for the 3 kW, 1.1 L for the 5 kW and 7 kW
• A propane cylinder: 19 kg for lighter setups, 47 kg for a full trading day
• The supplied hose and regulator — check both for cracks or damage before connecting
• Soapy water or leak-detection spray in a small spray bottle
• The supplied tool kit: funnel, spanners, plug spanner and Allen key
• A firm, level spot outdoors with 1 metre of clear space on every side

Step 1: Position the Generator Outdoors on Level Ground

Pick a dry, well-ventilated spot outside the trailer or van. Never run any generator inside — the exhaust contains carbon monoxide, which is invisible, odourless and can kill.

Keep at least 1 metre of clear space between the generator and buildings, your trailer, or anything flammable. The surface should be stable and level. Greengear engines tolerate a maximum tilt of 25° — on a sloped festival pitch, level the unit, not just the trailer.

Why: an unlevel unit gives false oil-level readings and can starve the engine of lubrication under load.

Step 2: Remove the Transportation Bolt (and Fit the Wheels)

Every unit ships with a centre transportation bolt and rubber sleeve locking the engine mounting bracket. Remove both before the first start. The manual is blunt about this: leaving it in can cause serious damage once the engine is running.

On the 5 kW and 7 kW models, wheels and handles come as standard. Fit them now with the supplied tool kit — at 93–96 kg, you won’t be lifting these units on your own.

Step 3: Fill the Engine Oil — It Ships Dry

Greengear generators leave the factory with an empty crankcase. Put oil in before you attempt the first start.

• GE-3000UK (3 kW): 0.6 litres
• GE-5000UK and GE-7000UK: 1.1 litres
• Grade: SAE 10W-30 or 10W-40 4-stroke oil suits UK temperatures year-round

With the unit level and the engine off, remove the oil filler cap and fill to the upper level line on the gauge. Don’t overfill.

Why: the built-in oil sensor stops the engine — or refuses to let it start — when the level drops too low. A brand-new generator that “won’t start” is nearly always a dry crankcase.

Step 4: Connect the Propane Cylinder and Leak-Test

Stand the cylinder upright on a firm, level base, away from the exhaust outlet. Keep the cylinder valve closed and the engine off while you connect.

1. Check the hose for cracks, abrasion or discolouration. Replace it if you find any
2. Connect the flexible hose to the LPG inlet on the generator. The threaded end screws on anti-clockwise
3. Connect the regulator to the propane cylinder
4. Tighten the nut at each end with a spanner — snug, not brutal. Over-tightening damages the seals
5. Spray soapy water on every joint and watch for bubbles. Listen for hissing. If anything leaks, don’t start the engine

Propane has a rotten-egg odour added so leaks are easy to smell. If you ever catch that smell while trading, shut the engine off and close the cylinder valve first, then investigate. Our LPG hose and regulator UK regs guide covers the standards your hose and regulator should meet, and our LPG cylinder sizes guide helps you pick between 19 kg and 47 kg.

Step 5: Start the Engine

The starting order matters. Follow it exactly:

1. Open the cylinder valve by turning it anti-clockwise
2. If your regulator has a reset button, press it
3. Press the primer button on the ENERKIT carburettor once or twice — no more. Over-priming floods the mixture and can harm the engine
4. Turn the circuit breaker to OFF so the generator starts with no load
5. Insert the key, turn to ON, then to START. Release as soon as the engine fires

Don’t crank the starter motor for more than 5 seconds at a time. If it doesn’t fire, return the key to ON, wait 10 seconds, and try again. The manual recommends using the recoil (pull) starter for the very first start of a new unit.

Why the breaker stays off: starting under load strains the engine and can trip the breaker instantly. Let it warm up first.

Step 6: Plug In Your Appliances — In the Right Order

With the engine running smoothly, turn the circuit breaker to ON. Check the voltmeter reads correctly. Then connect appliances one at a time.

• Switch each appliance OFF before plugging it in
• Plug in, then switch on — largest appliance first
• Keep the total wattage under the generator’s rated output

Remember surge: anything with an electric motor (fridges, pumps) briefly needs 3–5 times its running wattage to start. Size for the biggest surge, not just the total running load. If the breaker trips during service, you’re overloaded or an appliance is faulty — stop, unplug, and check before restarting.

Step 7: Shut Down and Pack Away Properly

1. Switch off and unplug every appliance
2. Turn the circuit breaker to OFF
3. Let the engine run with no load for about 3 minutes to cool down
4. Turn the key to OFF
5. Close the cylinder valve, and disconnect the cylinder if you’re done for the day

Why the cool-down: stopping a hot engine dead shortens its life. Three minutes at no load is cheap insurance on a unit you rely on for income.

Which Greengear Are You Setting Up?

Setup is identical across the range. The differences are output, weight and oil capacity:

Model	Rated output	Weight	Oil fill	Price
Greengear GE-3000UK	2.8 kW	49 kg (one-person lift)	0.6 L	from £649
Greengear GE-5000UK	5.0 kW	93 kg (wheels fitted)	1.1 L	from £949
Greengear GE-7000UK	7.0 kW	96 kg (wheels fitted)	1.1 L	from £1,249

Browse the full range on our LPG generators category page. All three run on a 47 kg propane cylinder — the 3 kW manages roughly 28 hours at half load on one.

Staying Safe While It Runs

• Carbon monoxide: outdoors only, always. If you feel headachy, drowsy or sick near the unit, shut it down and get fresh air fast
• Earthing: double-insulated (class 2) kit doesn’t need an earth electrode. If you run earthed (class 1) appliances, use a 30 mA RCD to protect against faults
• Don’t move it while running, and keep the air vents clear
• Rain: keep it dry. If it gets wet, wipe it down and dry it before starting — never hose it off
• Cylinders: store propane cylinders outdoors, never inside the van overnight

Your annual gas safety check with a Gas Safe registered engineer should cover the whole propane system on the unit — hose, regulator and connections included.

Common Mistakes to Avoid

1. Starting it dry. No oil from the factory. Fill first, always
2. Leaving the transport bolt in. Two minutes with a spanner versus a damaged engine mount
3. Skipping the leak test. Soapy water on every joint, every time you swap a cylinder
4. Starting with the breaker on. The engine should warm up before it takes load
5. Over-priming. One or two presses of the ENERKIT primer. More causes problems
6. Ignoring surge. A fridge that runs at 150 W can demand 600 W+ at startup. Size for the spike

Setting up power is one part of a bigger job — our off-grid mobile catering setup guide covers water and propane alongside it.

Frequently Asked Questions

Do Greengear generators come with oil?

No. Every Greengear ships with an empty crankcase. Fill with SAE 10W-30 or 10W-40 4-stroke oil before the first start — 0.6 litres for the 3 kW, 1.1 litres for the 5 kW and 7 kW. The oil sensor will stop a dry engine from running.

Can I run a Greengear generator on butane?

No — use propane only. Butane stops vaporising below about 2°C, so it fails exactly when UK outdoor traders need it most. Greengear units are built for propane, and all commercial mobile catering kit runs on propane at 37 mbar.

What size propane cylinder should I use with a Greengear generator?

A 47 kg cylinder suits full trading days — the 3 kW runs roughly 28 hours at half load on one. A 19 kg cylinder works for shorter sessions and is easier to move. Match cylinder size to your trading pattern and how you transport it.

Can I run the generator inside my trailer or van?

Never. Generator exhaust contains carbon monoxide, which is invisible, odourless and lethal in enclosed spaces. Run the unit outdoors in a well-ventilated spot, at least 1 metre from the trailer, buildings and anything flammable.

Do I need to earth a Greengear generator?

Not always. With double-insulated (class 2) appliances, no earth electrode is needed. If you run earthed (class 1) equipment, use a 30 mA RCD for fault protection. For connection to fixed wiring, a qualified electrician should do the work.

Why won’t my new Greengear generator start?

Check the oil first — the sensor blocks starting when the level is low, and new units ship dry. Then check the cylinder valve is open, press the primer once or twice, and crank for no more than 5 seconds at a time with 10-second rests.

How long does setup take?

Allow about an hour for the first setup: fitting wheels and handles, removing the transport bolt, filling oil, connecting and leak-testing the cylinder, and a first test run. After that, a routine pitch setup takes 10–15 minutes including the leak test.

What warranty do Greengear generators have?

Warranty support is back-to-base. If the fault is with the unit itself, collection and re-delivery are free. If the problem comes from damage or user error, you cover transport or use a service centre local to you. In our experience Greengear support in the first year is good.