# MotoRad 251-185 Engine Coolant Thermostat for 1990-1998 Mercedes E Class

### Specifications

Bypass Diameter: 1.64"

Bypass Length: 0.97"

Flange Thickness: 0.06"

Gasket or Seal included: No

Installation Tool Included: No

Jiggle Pin Weep Hole: Yes

Sealing Flange Outside Diameter: 2.64"

Temperature (Degree): 185F

### Features

-   Offer precise pressure control
-   Ensure the proper fit
-   Made of high quality materials
-   Easy installation

### Product Details

Engine Coolant Thermostat (251-185) by MotoRad®. Temperature: 185F. State-of-the-art equipment, strict quality control, and functional testing to each thermostat ensure customers that they can trust the high-quality product used in their vehicle. As cooling system experts, MotoRad knows what is necessary to manufacture a high-quality part that will stand up to the rigors of today’s demanding cooling system environments where others fail.

MotoRad offers a full line of thermostats to replace original equipment thermostats. These parts are manufactured with high-grade duel bridge stainless steel construction and they meet or exceed all original equipment manufacturer requirements. MotoRad also offers standard thermostats in many alternate temperatures.

Brand: MotoRad

Part Number: 251-185

UPC: 055644251851

Alternate MPN: 251185

OE Numbers: 42030975

### Vehicle Fitment Table

Year

Make

Model

Position

Fitment Precision

Note

1991

Mercedes

E Class

1992

Mercedes

E Class

1993

Mercedes

E Class

1996

Mercedes

E Class

1997

Mercedes

E Class

1998

Mercedes

E Class

1990

Mercedes

S Class

1991

Mercedes

S Class

1992

Mercedes

S Class

1993

Mercedes

S Class

1994

Mercedes

S Class

1995

Mercedes

S Class

### FAQ

**Will this fit my vehicle?**  
Please verify your year, make, model, position, and any fitment notes using the Vehicle Fitment Table above before purchase.

**What part number is this?**  
The listed part number is 251-185.

**Is this product designed for direct replacement?**  
Yes. This product is intended to match the compatible vehicle applications listed in the fitment table.

**Should I confirm fitment before ordering?**  
Yes. Always compare your original part, position, and vehicle details with the fitment table before ordering.

### Common Searches

-   Engine Coolant Thermostat for Mercedes E Class
-   251-185 fitment
-   MotoRad Engine Coolant Thermostat
-   1991 Mercedes E Class Engine Coolant Thermostat

## Details

- **Price:** 34.47 CAD
- **Vendor:** MotoRad
- **Type:** Engine Coolant Thermostat
- **Tags:** 1990-1995 Mercedes S Class, 1991-1993, 1996-1998 Mercedes E Class, 251-185, Automotive, Engine Coolant Thermostat, MotoRad

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 34.47 CAD | In stock |

## Images

- MotoRad 251-185 Engine Coolant Thermostat for 1990-1998 Mercedes E Class

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> Source: [Standard Auto Part](https://www.standardautopart.com/products/motorad-251-185-engine-coolant-thermostat)
> Updated: 2026-08-17