Cooling System Fluid Hydrometer (bulb) Forsage F-9G4001A – handheld hydrometer for antifreeze and coolant testing

Handheld cooling system fluid hydrometer in a glass bulb design by Forsage, model F-9G4001A. This hydrometer measures the density and specific gravity of engine coolants and antifreeze liquids to help determine freeze and boil protection and estimate coolant concentration. The simple suction operation and an easy-to-read graduated scale provide quick, visual results for workshop diagnostics and on-site vehicle maintenance.

Advantages

The hydrometer’s glass bulb construction delivers clear visibility of the floating indicator and scale, enabling straightforward interpretation of readings. Its handheld format and lightweight design make it convenient to carry and use in tight engine compartments. No power source is required, allowing immediate checks without setup. The device provides direct, passive measurement of fluid density suitable for routine maintenance and quick troubleshooting.

Suitable for

• Checking antifreeze concentration in passenger cars and light commercial vehicles
• Workshop coolant system diagnostics and preventive maintenance
• On-site inspections of radiator and coolant reservoirs
• Assessing freeze point and basic boil protection of ethylene- or propylene-glycol based coolants

Key specifications

• Handheld glass bulb hydrometer with float indicator and printed graduated scale
• Designed for measuring density/specific gravity of engine coolants and antifreeze liquids
• Passive suction operation; no batteries or power required
• Visual scale for quick assessment of freeze and boiling protection levels
• Compact, lightweight construction for easy handling in engine bays

How to use

Insert the hydrometer tip into a sample of coolant taken from the radiator or reservoir, then draw fluid into the bulb using the built-in suction method until the float is freely floating. Read the value indicated on the visible scale at eye level to evaluate specific gravity and approximate freeze/boil protection. After taking the measurement, release the fluid back into the reservoir or dispose of it according to local regulations and rinse the hydrometer with clean water to prevent contamination between samples.

Usage recommendations

For accurate readings, sample fluid after the engine has cooled and avoid mixing fresh and used coolant samples. Use the hydrometer primarily with ethylene- or propylene-glycol based coolants and follow vehicle manufacturer guidance for required freeze and boil protection levels.