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12_69c5d851-c694-4243-a481-a88755a43e62 - Northline Parts

105°C Water Temperature Alarm Switch for FG Wilson Gensets – 622-337

SKU: NLT2T04755
$31.29 In Stock
$31.29
Sale price  $31.29 Regular price 
Ships for free in 2–4 business days.
This 105°C water-temperature alarm switch fits compatible FG Wilson generator sets using part number 622-337 and a 3/8 NPT connection.
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Compatible Models

We do our best to list all compatible models. Although this may be the part you need, your exact model may not appear below.

Compatible equipment / model

Applications are grouped below. Equipment can vary by serial number, engine, and production configuration.

FG Wilson Gensets Compatible generator sets calling for 622-337
Perkins Engine Applications Selected 1103, 1104 and 1106-powered generator configurations using the matching switch

Product Overview

This cooling-system sensor/switch monitors engine temperature so the gauge, alarm circuit, or control system can respond when coolant temperature rises. A failed unit can produce a dead or inaccurate indication even when the cooling system itself is operating normally.

Parts listings identify 622-337 as a coolant-temperature alarm switch set around 105°C, with VDO reference 803/1/59 and use on generator sets powered by selected Perkins 1103, 1104 and 1106 engines. This is a warning switch, not simply a variable gauge sender.

Key Features & Performance

  • Cooling-system monitoring: Restores the temperature-sensing point used by the machine's gauge or warning circuit.
  • Threaded service replacement: Installs at the corresponding coolant passage when thread size and terminal configuration match.
  • Diagnosis-friendly repair: Useful after wiring, connector condition, coolant level, and actual engine temperature have been checked.

Part Numbers & Specifications

  • Part Number: 622-337
  • Switch Temperature: 105°C
  • Thread: 3/8 NPT
  • VDO Reference: 803/1/59
  • Electrical Range Reference: 6–24V / 3W as cataloged

Before You Order

Confirm 622-337, thread size, terminal style and whether the machine requires an alarm switch versus a variable temperature sender. Do not interchange the two functions solely by appearance.

Frequently Asked Questions

Is this an OEM part?
This is a replacement service part intended to interchange with the reference number(s) and applications listed here. It is not represented as a factory-branded OEM part unless the product packaging itself states otherwise.

How do I confirm fitment?
Match the original part number first, then confirm the machine model, engine, connector or mounting arrangement, and any serial-number break that applies to your equipment.

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