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MB GPW G503 WWII Jeep Check Theromostat On Engine

This article shows the steps how to Check your engine Theromostat On an MB GPW G503 WWII Jeep

This article applies to both Willys MB and Ford GPW WWII Military Jeeps 

1. This article shows a simple way to check your thermostat to see if it is opening up properly. First you need to remove the thermostat housing from the top of the engine.

2. The thermostat is in the thermostat housing. You will need some needle nose pliers to pull the theromstat retainer out of the housing.

3. The thermostat will be sitting on top of the retainer. NOTE: there are a wide variety of thermostats, so it may look different than the pictures shown in this article.

4. Take your thermostat and place it in a pan of water on your stove. Turn the heat on high because you want to bring the water to a boil.

5. If you have a cooking thermometer, then monitor the heat of the water. In this case, I know my thermostat is a 160 degree thermostat, so I expect it to open up when I reach this temperature.

6. In this case, the thermostat starts opening at 160 degrees, and shows that it is working and completely open at 170 degrees.

7. In this case, I dumped the water, and with a towel wipe off the thermostat for inspection. BE CAREFUL it is still hot. You can see that the thermostat is fully open. As it cools it will start to shut.

8. Now replace the thermostat back in the retainer and housing. Replace the gasket on the head and tighten down. In this case the thermostat was just fine. If your thermostat does not open... then it needs to be replaced!

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