A better test than running without a thermostat would be to make a plate the same diameter as a thermostat with a one inch hole. Running without any restriction in the flow could give mixed results because of the possibility of cavitation.
Water pump replacement on FJ40
- Thread starter agouge888
- Start date
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I just want to see if I have any type of flow through my radiator with this test. I don't plan on leaving it without a thermostat.
When you open the block drain, does it drain?
Oh yeah it drains really good through the block through everywhere. I really I flushed it and back flushed it probably 10 times about 8 months ago and about eight times this time.
I ran it today at idle and it stayed about Midway for about a half an hour. This is with no thermostat only distilled water. I drove it for an hour and it pretty much got up to the furthest to the right next to the h tick mark, but it did not go. It did not actually get to the tickle Mark before the h so it was running hot but I don't think it was actually overheating too much got home. Let it sit. Going to try it again tomorrow and burp it again. Just curious because I was thinking without the thermostat it would be actually running cool. Joe with the thermostat that'll be more pressure. So will it run a lot hotter and that's why I was overheating still. So now I'm wondering if there's an issue with my water pump and not it is brand new. I just installed it and it is OEM but not sure if the water pump is flowing with enough pressure all working properly but I guess if it wasn't working properly I would have never made it home after an hour
any updates? still overheating?
Sorry it's been awhile, no, it is not overheating anymore. I did run a secondary thermostat in the top hose which began to leak the other day so I removed it and replaced it with a silicone top hose. No issues now. By having that secondary thermostat giving me an actual digital readout of the temperature that helped me know if I was really overheating and not. I don't think I was really overheating. If I was it was only because there was air in the system and it just took a couple weeks to get it all out. Once I got it out there was issues with my gauge so I had to fix it. I wanted up restoring my whole gauge cluster painting and everything
I am really looking to use one of the screw in ports either Forward or aft of the original temperature sensor location so I don't have to drain all the fluid out
The aftermarket gauge the temp prong it's too long that's why I did it at the front.
Got ya, thank you
sleepycruiser
I will get by….I will survive
Does anyone have the torque specs for the 4 bolts securing the water pump to the block? Also, my thermostat housing has studs and is held by nuts….anyone know the torque specs for those? I’ve looked all over and finding conflicting specs. 1964 FJ40
Try this thread: < click here >