Thermostat – Fits Johnson/Evinrude 185-225HP (Replaces 0437090, 437090, 0436174)
Thermostat – Fits Johnson/Evinrude 185-225HP (Replaces 0437090, 437090, 0436174) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
Orders are typically processed within 1–2 business days.
U.S. orders usually arrive within 6–15 days, depending on stock location and destination.
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Thermostat – Fits Johnson/Evinrude 185-225HP (Replaces 0437090, 437...
Thermostat – Fits Johnson/Evinrude 185-225HP (Replaces 0437090, 437090, 0436174) is backordered and will ship as soon as it is back in stock.
Product Details
This aftermarket Thermostat – Fits Johnson/Evinrude 185HP, 200HP, 225HP is a high-quality replacement designed for Johnson/Evinrude 185–225 HP V6 outboard engines from 1993–1994. It ensures your engine maintains the correct operating temperature for optimal performance and fuel efficiency.
It serves as a direct interchange for Johnson/Evinrude part numbers 0437090, 437090, 0765585, 0436174, and 0435100, and also cross-references with Sierra 18-3545 and Mallory 9-43031.
- Installs as a direct OEM-equivalent replacement.
- Compatible with all standard marine fuel types.
- Manufactured in an ISO9002 certified factory to meet or exceed OEM specifications.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Johnson/Evinrude | 0437090 / 437090 |
| Johnson/Evinrude | 0765585 |
| Johnson/Evinrude | 0436174 |
| Johnson/Evinrude | 0435100 |
| Sierra | 18-3545 |
| Mallory | 9-43031 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This part fits specific Johnson models starting with J185, J200, J225, and VJ225 from 1993–1994.
This part fits specific Evinrude models starting with E185, E200, E225, and VE225 from 1993–1994.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Johnson | J185 series | 185 | 2-Stroke | 1993–1994 | 0437090, 437090 | All models starting with J185 |
| Johnson | J200 series | 200 | 2-Stroke | 1993–1994 | 0437090, 437090 | All models starting with J200 |
| Johnson | J225 series | 225 | 2-Stroke | 1993–1994 | 0437090, 437090 | All models starting with J225 |
| Johnson | VJ225 series | 225 | 2-Stroke | 1993–1994 | 0437090, 437090 | All models starting with VJ225 |
| Evinrude | E185 series | 185 | 2-Stroke | 1993–1994 | 0437090, 437090 | All models starting with E185 |
| Evinrude | E200 series | 200 | 2-Stroke | 1993–1994 | 0437090, 437090 | All models starting with E200 |
| Evinrude | E225 series | 225 | 2-Stroke | 1993–1994 | 0437090, 437090 | All models starting with E225 |
| Evinrude | VE225 series | 225 | 2-Stroke | 1993–1994 | 0437090, 437090 | All models starting with VE225 |
Technical Specs
- Product Type
- Thermostat
- Installation
- Direct OEM replacement
- Fuel Type
- Compatible with all marine fuels
- Connection
- Direct mounting in thermostat housing
- Housing Color
- Silver/metallic
- Other Technical Attributes
- Manufactured to OEM specifications in ISO9002 certified factory
What’s in the Box
- 1 x Thermostat (0437090/437090)
Installation Notes
- Disconnect the negative battery cable before beginning work.
- Allow the engine to cool completely and drain the cooling system.
- Locate the thermostat housing on the engine block.
- Carefully remove the bolts securing the housing cover.
- Remove the old thermostat and gasket. Note the orientation of the thermostat.
- Thoroughly clean the mating surfaces of the housing and cover, removing all old gasket material.
- Install the new thermostat in the correct orientation (typically spring-side towards the engine).
- Position a new gasket and reinstall the housing cover, tightening bolts to the manufacturer's specified torque.
- Refill the cooling system with the appropriate coolant.
- Reconnect the battery, start the engine, and carefully check for leaks as it warms up.
Troubleshooting & FAQ
How do I know if my thermostat has failed?
Common signs of a faulty thermostat include the engine overheating at low speeds or running too cool and failing to reach its normal operating temperature. An inconsistent temperature gauge reading can also indicate a problem.
Is a new gasket required for installation?
Yes, it is strongly recommended to replace the thermostat housing gasket whenever you replace the thermostat. This helps ensure a proper seal and prevent coolant leaks. This package contains the thermostat only.
What are the signs of a failing thermostat?
Symptoms include engine overheating (especially at idle or low speeds), the engine taking an unusually long time to warm up, or erratic temperature gauge readings. An engine that runs too cool can suffer from poor performance and efficiency.
How often should a marine thermostat be replaced?
There is no fixed interval, but thermostats are a common wear item. It's good practice to inspect it during regular cooling system service or replace it every few hundred hours or every few years, especially if operating in saltwater.
My engine model is listed, but my year is 1995. Will this fit?
No. This thermostat is specifically for models from 1993–1994. Engine parts can be highly year-specific. Do not purchase if your model year falls outside the specified range.
What is the difference between OEM and this aftermarket part?
This listing is an aftermarket replacement, not an OEM component. It has been engineered and manufactured to meet or exceed OEM-level specifications using comparable materials in an ISO 9002 certified facility and is batch-inspected for quality and consistency.
How fast is shipping?
We ship worldwide quickly—typical transit is 5–15 days. Standard shipping is free for most regions, with expedited options available at checkout where applicable.
What is the warranty and return policy?
This product is covered by a 1-year warranty against manufacturing defects under normal marine use. Should an issue arise, contact our support team with your order details. Returns are accepted within our standard window if the item is unused and in its original packaging. Please see our full policy page or contact us for instructions.
Safety & Important Info
- Verify images and specifications against your original part before ordering. If anything differs—even if your model appears compatible—do not purchase.
- This is an aftermarket replacement component, not an original equipment manufacturer (OEM) part.
- Professional installation is highly recommended for safety, proper function, and to avoid engine damage.
About Sea Sierra
- Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
- Fast Global Fulfillment — Free standard delivery to most regions, typically arriving in 5–15 days.
- Manufacturer-Direct Value — We offer fair pricing without compromising on materials or quality control by working directly with our manufacturing partners.
Payment & Security
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