Engine Coolant Thermostat Guide for the 1951-1952 Dodge B-3
Keep your B-3's flathead engine running at the right temperature with the right thermostat.
- Aftermarket thermostats are the standard for this truck; choose a 160°F or 180°F rating based on your climate.
- Symptoms of failure include overheating, the engine never warming up, or coolant leaks from the housing.
- This is a very simple and inexpensive DIY repair that most owners can do in under an hour.
- Brands like Gates and Motorad offer reliable, standard-quality replacements suitable for the B-3's flathead engine.
Is Your Dodge B-3 Thermostat Failing?
The simple cooling system in these classic Dodge trucks is reliable, but the thermostat is a wear item that will eventually fail. Failures happen in two ways: stuck open or stuck closed. Both can cause problems.
| Symptom | Cause | What to Look For |
|---|---|---|
| Engine Overheating | Thermostat is stuck closed. | The temperature gauge climbs into the red zone. You might see steam from under the hood or smell hot coolant. This is serious and can cause engine damage. |
| Engine Never Warms Up | Thermostat is stuck open. | The temperature gauge stays low, even after driving for a while. Your heater will not blow hot air, and fuel efficiency may decrease. |
| Coolant Leaks | Failed housing or gasket. | You may see coolant dripping from the thermostat housing, which is located where the upper radiator hose connects to the engine. |
Choosing the Right Aftermarket Thermostat
For a 1951-1952 Dodge B-3, you won't be walking into a dealer and buying a new Mopar part. "New Old Stock" (NOS) parts are sometimes available, but they can be expensive and unreliable after sitting on a shelf for 70 years. One owner reported that an NOS thermostat he purchased failed to work at all. Aftermarket thermostats are the standard, reliable choice for these trucks.
The most important choice you'll make is the temperature rating. These flathead engines originally used a 160°F or 180°F thermostat.
- 160°F Thermostat: A good choice for warmer climates or if your truck is used for heavy hauling. It opens sooner to start the cooling process earlier.
- 180°F Thermostat: Ideal for cooler climates and general use. Running the engine a bit hotter helps burn off moisture and contaminants in the oil, which is good for engine life. Many owners of similar vehicles prefer a 180°F thermostat.
Pro Tip: Many owners have found that modern thermostats designed for later Mopar engines, like the 318 V8, fit and work perfectly in the flathead six. This gives you more high-quality options.
Brand Quality Breakdown
You have several good aftermarket brands to choose from. For a stock B-3, you don't need a fancy high-performance part, just a reliable one.
- Gates: A well-respected brand in cooling systems. Gates thermostats are known for their reliability and are a solid choice for any B-3 owner.
- Motorad: A major manufacturer that produces thermostats for many brands, sometimes even in boxes labeled with other names. They are a common, standard-quality replacement part.
- Edelbrock: Known for performance parts, their thermostats are built to be very stable. While it might be overkill for a stock truck, it is a high-quality option if you find one in the right temperature range.
Cost of Replacing a Dodge B-3 Thermostat
This is an inexpensive and straightforward repair.
| Part/Service | Estimated Cost |
|---|---|
| New Aftermarket Thermostat | $7.93 - $26.61 |
| Shop Labor | $90 - $150 |
| DIY Cost (Part Only) | $7.93 - $26.61 |
Frequently Asked Questions
Is replacing the thermostat a good DIY job?
Yes, this is a great job for a beginner. It requires basic hand tools, a drain pan for coolant, and a scraper to clean the old gasket material off. The thermostat is easily accessible at the top of the engine.
Should I replace the radiator hoses at the same time?
Absolutely. If your hoses are old, feel brittle, or are bulging, it's a perfect time to replace them. You already have to remove the top hose to get to the thermostat, so it's very little extra work.
Do I need a special type of coolant?
For these vintage trucks, a conventional green or yellow ethylene glycol-based coolant is the correct choice. Be sure to mix it 50/50 with distilled water. Using tap water can cause corrosion and deposits in the cooling system.
Are there any recalls or TSBs for the thermostat?
No. There are no active recalls or Technical Service Bulletins (TSBs) from the NHTSA for the engine coolant thermostat on a 1951-1952 Dodge B-3. This is normal for a vehicle of this age.
Technical Specifications
OEM Part Numbers: 1111010
Temperature Rating: 160°F or 180°F
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The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.