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@ToyotaMatt you got a part number for the nut that would go on the studs for the thermostat housing?
Nope, it’s yours in my book.
@letterman52
I cant take credit for the idea. Another mud member & vendor @ToyotaMatt mentioned using a stud in place of a bolt. I just stumbled across a proper length stud.
They were out.
Did the FJParts gasket end up being 3mm thick?
@ToyotaMatt you got a part number for the nut that would go on the studs for the thermostat housing?
Thanks for the great write up. I just replaced my thermostat but it hasn’t change the status. What temps are you seeing at the housing? I can’t tell if my reader/sender is bad or if my coolant is too hot. 205 at the thermostat housing, about the same at the top of the radiator then 135 exiting the radiator. Normal? Or too hot?Since it has been nine years since a thread has been created discussing the installation of a thermostat on a 2F engine, and since I spent about 30 minutes yesterday trying to figure out how to do the installation correctly with the odd gaskets that are included in different rebuild kits, I thought I would quickly show the steps that one would take to properly (hopefully) install the thermostat. (Also the old thread has lost its picture links)
EDIT 8/12/19: Cool Cruisers and SOR have gaskets (upper, lower - thick and thin) readily available. Search on their sites for "thermostat gasket". Not sure (it's been a while) but there may be OEM parts available as well. Search on your favorite Toyota parts website).
1. On a cool engine, locate the thermostat. It is on the front on the straight 6 engine (F thru 3FE). In the photos below it is circled in yellow.
View attachment 1479621 View attachment 1479622
Place a bucket or pan underneath and loosen the hose clamps. Allow the coolant to drain into the bucket.
2. Remove the top half of the thermostat housing by removing the two bolts. Remove them slowly and carefully as these have a high tendency to break within the aluminum housing. They are fairly thin and long, and bind up in the aluminum due to the increased exposure to water.
View attachment 1479628
3. Remove the old thermostat from the housing if you are going to replace it with a new one. If you are not then you should test the thermostat to make sure it still works by placing it in a pot of water and monitoring the temperature until it reaches the proper expansion temperature. At that time the thermostat should expand.
4. Remove the old gasket. Clean the lower and upper mating surfaces of any residue from the old gasket. Use a razor blade to scrape for material from the face of the thermostat housing, and then use a cleaning agent like general spirits, brake cleaner, or other non-residue creating cleaner to remove the oil from the surface.
5. Insert the thermostat with the visible spring facing down and the domed part up. It should fit into the lip in the lower housing. Install the thermostat so the "jiggle valve", as the FSM describes it, is located at the 11 to 1 o'clock position in the housing. It allows a little circulation until the thermostat opens. (NOTE: the thermostat pictured below does NOT have a jiggle valve).
This is the bottom:
View attachment 1479629
This is the top:
View attachment 1479630
Thanks for the great write up. I just replaced my thermostat but it hasn’t change the status. What temps are you seeing at the housing? I can’t tell if my reader/sender is bad or if my coolant is too hot. 205 at the thermostat housing, about the same at the top of the radiator then 135 exiting the radiator. Normal? Or too hot?
I was thinking about replacing my thermostat on a 1978 FJ40 because it is so old but after reading this thread, I am hesitant to tear into if for fear of breaking bolts and gasket issues. Can I use the four bolt system available for 1980+ models without any issues? Does it make sense to install the 4 bolt kit rather than trying to deal with the current 2 bolt system? Did anyone ever figure out what the 12 o'clock reference was to? front of engine to back or back to front?
I was thinking about replacing my thermostat on a 1978 FJ40 because it is so old but after reading this thread, I am hesitant to tear into if for fear of breaking bolts and gasket issues. Can I use the four bolt system available for 1980+ models without any issues? Does it make sense to install the 4 bolt kit rather than trying to deal with the current 2 bolt system? Did anyone ever figure out what the 12 o'clock reference was to? front of engine to back or back to front?