100TECH Fuel Sending Unit 240-33 ohms 8in - Durable Stainless Steel

In this review the 100TECH fuel sending unit is assessed as a straightforward replacement for arm type senders used in boats, trucks and RVs; the single biggest reason to buy is its durable reed switch design which eliminates delicate moving contacts. For anyone wanting a reliable, no-adjustment fuel or water level sensor with standard American 240-33 ohm output, this unit delivers dependable readings and simple fitment. The review focuses on installation, build quality and how the sender performs in typical marine and vehicle tanks.

Key Features

• OKI reed switch: Imported reed switch provides long service life and greater reliability than thick-film swim arm designs, reducing failure from repeated cycles.
• 316 stainless construction: Heavy duty materials and heli-arc style welds resist corrosion in marine environments and give a robust feel during fitting and handling.
• Standard output: 240-33 ohm output (240 ohm empty, 33 ohm full) works with American standard gauges for straightforward gauge compatibility.
• Easy installation: Ships with gasket, mounting screws and clear illustrated instructions so wiring and mounting follow a simple process for most DIY installers.
• SAE 5-hole pattern: Common mounting pattern fits many existing tanks and makes replacement less likely to require tank modification.
• Float size guidance: Float diameter of 1.38in and suggested drill hole of 1.50in helps installers plan tank entry and clearance.

Who It's For

The 100TECH sender suits boat owners, RV builders and light truck owners who need a durable direct replacement for an arm type fuel sender and value long-term reliability over cheaper moveable-arm designs. It is particularly useful for those who prefer a stainless steel assembly and a sensor that requires no in-tank adjustments after installation.

It is less suitable for users who need a nonstandard length outside the 4in-32in range without contacting the maker, or for installations where clearance below the top of the tank is tighter than the unit length minus the recommended 1in allowance to avoid hitting the tank bottom.

Pros & Cons

Pros

• Durable reed switch eliminates fragile moving electrical contacts for improved longevity.
• Solid 316 stainless construction and quality welds give good corrosion resistance and a professional fit.
• Includes gasket and screws with clear wiring instructions for a straightforward installation.
• Standard 240-33 ohm output ensures compatibility with common American gauges.

Cons

• Limited to stated lengths; installers needing custom lengths must contact the supplier.
• The installer must measure tank depth carefully and allow the recommended 1in clearance to avoid the sender hitting the bottom.

Specifications

Our Verdict

The 100TECH 240-33 ohm 8in fuel sending unit is a practical, cost-effective replacement for arm type senders that prioritizes durability and ease of installation. Its reed switch and 316 stainless construction make it a good choice for marine and vehicle use where longevity and corrosion resistance matter, and the included hardware and instructions minimize installation headaches.

Frequently Asked Questions

What is the electrical output?
The sender uses the American standard 240-33 ohm output, 240 ohm at empty and 33 ohm at full.

Does it include mounting hardware?
Yes, the unit ships with a gasket, mounting screws and illustrated instructions for installation.

How do I avoid the sender hitting the tank bottom?
Measure the outside tank depth and subtract 1in from the sender length to ensure adequate clearance inside the tank.