U85206500 Perkins Fuel Shut-off Solenoid (also known as a fuel cut-off solenoid or stop solenoid)—often referred to as a throttle solenoid or idle control solenoid—is primarily used to control the fuel supply and shut-down of diesel engines.

I. Core Parameters

Model: U85206500

Brand: Perkins (UK)

Type: Fuel Shut-off Solenoid / Throttle & Idle Control Solenoid

Voltage: 12VDC (Common) / 24VDC

Function:

Energized: Solenoid engages, opening the fuel passage; engine starts/runs.

De-energized: Solenoid resets, cutting off the fuel passage; engine shuts down.

Assists in controlling engine idle speed; suitable for heavy-duty operating conditions.

Compatible Engines: Perkins 400 Series (402, 403, 404, 403D, 404D, 404C, etc.) small diesel engines.

II. Compatible Models and Applications

Construction Machinery: Mini excavators, skid steer loaders, road rollers, asphalt pavers.

Generator Sets: Perkins 400 Series-powered generator sets.

Agricultural Machinery: Tractors, combine harvesters, small-scale farm equipment.

Industrial Equipment: Air compressors, water pumps, welding machines, forklifts.

IV. Common Faults and Diagnostics

Fault Symptoms: Engine fails to start; engine starts but immediately shuts down; unstable idle speed; engine fails to shut down; solenoid coil overheats or burns out.

Diagnostic Methods:

Measure coil resistance (Normal range: approx. 3–6 Ω for 12V; approx. 10–15 Ω for 24V).

Power-on Test: A distinct "click" sound indicating engagement/reset should be heard.

Check for a stuck valve spool, clogged fuel passages, or short circuits/open circuits in the wiring harness.