{"product_id":"marvelity-petrol-cylinder-compression-tester-kit-9pc-with-spark-plug-tester-0-300-psi-gauge-rust-resistant-adapters","title":"Marvelity petrol cylinder compression tester kit 9pc with spark plug tester — 0–300 PSI gauge, rust-resistant adapters","description":"\u003cp\u003e\u003cstrong\u003eThe Marvelity 9-piece petrol cylinder compression tester kit lets you accurately measure spark-ignition engine compression and quickly check ignition circuit function with a spark plug tester.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eWhether you're servicing motorcycles, lawn mowers, ATVs, or small cars, this compact diagnostic set combines a large dual-scale gauge, multiple adapters, and a spark-check tool so you can evaluate cylinder health and basic ignition at the workshop or roadside. Components are treated to resist rust and corrosion, and the kit excludes diesel engines.\u003c\/p\u003e\n\n\u003ch3\u003eHow do I use the Marvelity tester to check cylinder compression?\u003c\/h3\u003e\n\n\u003cp\u003eTesting compression is straightforward: remove the spark plug, screw in the correct adapter, crank the engine several revolutions, and read the peak pressure on the gauge. Repeat the test two or three times per cylinder to confirm consistent readings before drawing conclusions.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eSelect the matching M10\/M12\/M14\/M18 adapter for your spark plug thread depth.\u003c\/li\u003e\n  \u003cli\u003eAttach the 14-inch hose and quick-connect fittings—no threaded installation required.\u003c\/li\u003e\n  \u003cli\u003eCrank the engine with the throttle open and observe the built-in check valve for accurate peak pressure.\u003c\/li\u003e\n  \u003cli\u003eUse the one-hand release valve to safely bleed pressure before removing the hose.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat readings should I expect and what do they mean?\u003c\/h3\u003e\n\n\u003cp\u003eThe gauge displays pressure up to 300 PSI (0–20 bar) on a clear 3\" dial, helping you compare cylinder values across the engine. Moderate variations may be normal; large differences indicate potential issues such as worn rings, leaking valves, or head gasket faults.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eConsistent readings across cylinders suggest healthy sealing and compression.\u003c\/li\u003e\n  \u003cli\u003eSignificantly lower pressure in one cylinder implies a loss of sealing or combustion compression.\u003c\/li\u003e\n  \u003cli\u003eUse repeated measurements and confirm with a leak-down or professional inspection for definitive diagnosis.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow does the included spark plug tester help diagnose ignition problems?\u003c\/h3\u003e\n\n\u003cp\u003eThe spark plug tester lets you quickly verify whether the ignition circuit produces a spark under running conditions. Connect the rubber boot to the plug, touch the metal probe to the coil, and observe the spark while cranking—the visual flash shows a complete ignition path.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eDetects faulty plugs, damaged ignition cables, or weak coil output at a glance.\u003c\/li\u003e\n  \u003cli\u003ePortable and safe when used with the vehicle’s correct grounding and following instructions.\u003c\/li\u003e\n  \u003cli\u003eComplements compression testing to separate mechanical from ignition-related failures.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho is this kit designed for? Home mechanics, small-engine technicians, and DIY enthusiasts who service petrol engines will find this Marvelity set useful for routine troubleshooting and pre-purchase checks. It’s built for portability and durability, offering quick diagnostics for motorcycles, scooters, lawn equipment, ATVs, go-karts, and most gasoline cars (not suitable for diesel engines). Read the manual before use, follow safety steps, and repeat measurements to ensure reliable results. Marvelity provides support for product issues and stands behind the kit's workmanship.\u003c\/p\u003e\n\n\u003csection class=\"product-faq-snippet\"\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Is this compression tester suitable for diesel engines?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: No. The Marvelity kit is designed for petrol (spark-ignition) engines only, not diesel engines.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Does the kit include different thread adapters?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes. It includes M10, M12, M14, and M18 adapters to fit most spark plug threads and depths.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"Marvelity","offers":[{"title":"Default Title","offer_id":55163955806551,"sku":"B0FYLT3VC3","price":31.74,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1050\/1524\/7191\/files\/marvelity-front-packaging.jpg?v=1790348430","url":"https:\/\/britishgarage.co.uk\/products\/marvelity-petrol-cylinder-compression-tester-kit-9pc-with-spark-plug-tester-0-300-psi-gauge-rust-resistant-adapters","provider":"British Garage","version":"1.0","type":"link"}