Hey guys this may seem to be a dumb question but today, as I was checking my oil I was also trying to figure out how to read my coolant level. Since I have a jdm Japanese car I found a white tube and a cap on the drivers site, leading to a reservoir near the wheel. However, how do I find out how much is in it?? Can someone explain this to me with pictures.

I have been googling and checking the board but I didn't find an answer.

 

When the engine is cold from sitting 1+ hours, check coolant level at the Air Separator Tank. Don't open the cap when the engine is warm, hot coolant will be pressurized and can spray out and burn you.

 

The Coolant overflow tank should have some coolant inside it also, but that's not the right place to check engine coolant level. On old cars the rubber hoses between the coolant overflow tank might not be air-tight which would prevent coolant from going back into the Air Separation tank as the engine cools down.

 

Thanks man, this is valuable information. I will check it tomorrow. 🙂

 

After checking the level of my coolant today I found out I had more than enough in it. However, really funny, but shortly after that I filled up my tank and after starting the car I heard this super loud beep and my coolant light was on. I turned the engine off and started the car again and the beeping and light went away. Probably a sensor bugging?

 

Ok so only when warm the coolant overflow is the place to check the level? I see you check it at the AST. I would think you check it at the filler cap since this is the highest point and the place to fill it. I also have read on here once filled never open the ast again. Should i just check both caps maybe

 

I just make sure I know something is in the overflow and check the filler cap.

 

Could it be that the coolant sensor was bugging because of opening the AST? Als on cold start the engine temp is at 3/4 instead of half. It drops to normal after driving and warming up slowely though.

 

Yes that's probably right to check at the filler cap instead of the AST. I deleted my AST years ago, so it's been a while since I've needed to keep track of both. I would fix my original post to avoid spreading misinformation, but the forum doesn't appear to let you make edits after some time has passed.

The coolant buzzer uses a sensor in the thermostat housing (near the filler neck), so if you lost coolant while the AST was open that might be why the buzzer turned on.

The coolant temp on the dash checks the temperature in the rear iron. If that shows hot while the engine is still warming up, my guess is a possible problem with the thermostat or water pump.

 

Thanks I guess I need to check this Saturday, I'll update you guys as soon as I know more. I also talked to someone else and he basically said that if you find enough coolant in the filler neck, ast and reservoir there shouldn't be any coolant problems. So I guess it's better to check it all, unless you deleted your ast.

 

I always checked my overflow. I would snack the plastic tab to get liquid off and dip it and check it. Every day before taking her out I would check the over flow cap and fill up to the top of it needed any.

 

Assume that's in addition to checking the fill neck. The overflow level basically just ensures there's adequate fill when the system pulls from the tank. Of course, if it's low, your fill may be low as well, but it's not an indicator of level of coolant in your system.