Jump Starter Engine Size Rating

The engine size rating is the largest engine, in litres, that a jump starter is rated to start. Makers often give separate limits for petrol and diesel.

Last updated: 19 October 2026

What it means

A UK seller lists the NOCO GB20 with a petrol limit of 4.0 litres and no diesel limit ^[1], and the NOCO GB50 with a petrol limit of 7.0 litres and a diesel limit of 4.5 litres ^[2]. GOV.UK’s vehicle information service shows a vehicle’s engine size and fuel type from its registration number, without giving a unit ^[3].

Why it matters when you buy

Check the limit for your fuel. If a pack lists no limit for your fuel, as the GB20 listing does for diesel, the listing does not show that it suits your engine ^[1]. Ask the seller or the maker before you buy.

A worked example

A 1.6 litre petrol car is covered by a pack rated for petrol up to 4.0 litres, because 1.6 is under 4.0. A 2.0 litre diesel is not covered by the same pack, which lists no diesel rating. A pack rated for diesel up to 4.5 litres covers the 2.0 litre diesel with 2.5 litres to spare.

Illustrative scenario: figures are examples, not quotes, valuations or market prices.

Related

• What size jump starter do I need?
• Peak amps
• Cold cranking amps (CCA)
• Jump starters: how to choose

Sources

1. NOCO GB20 Boost Sport 500A jump starter, Tayna (UK seller listing), tayna.co.uk. Checked 19 October 2026.
2. NOCO GB50 Boost XL 1500A jump starter, Tayna (UK seller listing), tayna.co.uk. Checked 19 October 2026.
3. Get vehicle information from DVLA, GOV.UK, gov.uk. The page shows no date. Checked 19 October 2026.