Hey my 86 has been a little too warm. Above the middle mark. This time i know it's actually happening because the fans would turn on. This will happen when it's idling randomly too.

I haven't changed the thermostat or water pump since i got the car. Would this be a problem??

Coolant in the reservoir is at MAX mark and in the radiator it's not filled to the neck because it just goes in the reservoir is that okay?

The thermostat could be seized shut. Try that first......you can remove it and put it in some boiling water and see if it opens up before buying a new one.

how far down in the radiator is the coolant? it should be at least up to the nozzle that goes to the overflow tank. If it's not, you might have an air pocket in the coolant system, which can also cause inaccurate temp readings.

But I'd say first stop is a thermostat check. they're relatively cheap, so if you're opening up the housing to look at one, it's easy-peasy to put in a new one anyways.....

Also, what's your coolant mixture like? have you tested it with a hygrometer to make sure it's a decent mix?

--sarge

notnilc20 wrote:The thermostat could be seized shut. Try that first......you can remove it and put it in some boiling water and see if it opens up before buying a new one.

Since i'm taking it out shouldn't i just get a new one? Which one is recommended?

SgtRauksauff wrote:how far down in the radiator is the coolant? it should be at least up to the nozzle that goes to the overflow tank. If it's not, you might have an air pocket in the coolant system, which can also cause inaccurate temp readings.

But I'd say first stop is a thermostat check. they're relatively cheap, so if you're opening up the housing to look at one, it's easy-peasy to put in a new one anyways.....

Also, what's your coolant mixture like? have you tested it with a hygrometer to make sure it's a decent mix?

--sarge

It is below the nozzle. I will top it off but my OVERFLOW tank is always at FULL not between MIN and FULL level. Why is that all the coolant from radiator goes there and maxes it out? shouldnt it be in the middle? I even tried bleeding the air but the coolant was not moving at all. There was no bubbles what so ever.

Here's a photo. It's lower than the 2nd line btw. Looks higher in photo
http://puu.sh/vgux9/fd5f272b64.jpg


I will open the thermostat and replace.

No i am not sure what my mixture is like i was thinking of doing a complete flush. But the thing is that i have a aftermarket radiator KOYORAD. Toyota said I need 1 gallon for coolant. Is that true it's the same even if i have a after market radiator?

Swooki wrote:Since i'm taking it out shouldn't i just get a new one? Which one is recommended?

get a new one if it would make you feel comfortable....the boiling water test is just done to verify if that is your problem or not, rather than just replacing parts blind until it's fixed.