Ae95 Cooling Issues

[Womble1972]

I think my AE95 is running hot (4AFE with a manual box)

Its showing halfway on the temp gauge after 40 mins of use but when i feel the bottom hose it feels warm only.

I have

Replaced the thermostat with a toyota one which i placed into 85 deg water it opened and seemed fine.

Removed the water pump, all good. (flushed the metal pipe that runs behind the engine)

Removed the raditator fed water through it backwards.( a bit of orange rust)

Removed the head replaced the head gasket, cleaned all the jackets out while there.

It is not using water it, runs good.

The cooling fans only come on for a brief moment.

Still I don't think its right, that bottom hose seems too cool to me.

Any other ideas how to check if its ok working correctly?

Thank you in advance

Rod

[corollaparts69]

Hello, sounds like the only thing left is the heater hoses and core.Have you checked them?? I have 4 corolla's at the moment and each one has its own different operating temperature.One sits on halfway mark and another barely registers on the guage.None has actually overheated,so I have left them as is.I put it down to the fact that the car at half temp has air-con,steer etc,which makes it run a bit higher.Thank you.

[Womble1972]

Hello, sounds like the only thing left is the heater hoses and core.Have you checked them?? I have 4 corolla's at the moment and each one has its own different operating temperature.One sits on halfway mark and another barely registers on the guage.None has actually overheated,so I have left them as is.I put it down to the fact that the car at half temp has air-con,steer etc,which makes it run a bit higher.Thank you.

Hello

My heater is working and there are no hose leaks but apart from that i have not checked the heater system.

Stupid question time.

How do i check the heater core? I have never needed to do this any help would be great.

Thanks

Rod

[ke70dave]

is "half way" hot? isnt that about normal temp?

 

assuming the 4afe engine is the same water system as 4age

 

http://www.billzilla.org/4agwater.gif

 

that above photo/image to me sais that hot water flows out of engine into the top of the radiator, and then "cool" water flows out of the bottom radiator back into engine, so the bottom hose should be not as hot as the top hose?

 

if you are still worried about it, have you considered air bubbles in the system?

 

maybe you need to bleed the system.

 

so when its cold park it on a hill so your radiator cap is highest point, start car up from cold with radiator cap off, and just let it idle up to temperature, keeping an eye on the level in the radiator, if bubbles come out the level will drop, just top it back up again.

 

the other thing you can do is wait till the thermostat opens (you will see the water starting to rush around your radiator) then grab hold of the hoses and give them a few decent squeezes, and if there are any bubbles this squeezing can help force the bubbles out.

[corollaparts69]

Hello

My heater is working and there are no hose leaks but apart from that i have not checked the heater system.

Stupid question time.

How do i check the heater core? I have never needed to do this any help would be great.

Thanks

Rod

 

Hello Rod, when it cones to cars,there are no stupid questions.Only stupid drivers.

To check/flush heater core just disconnect hoses from the core,where it meets at the firewall(passenger side)and flush it like you do with a radiator.Best to check the hoses too.Hope that helps...Thank you.

[rthy]

half way should be normal?

 

is that the bottom hose from the radiator to the engine?

[delaney]

mines a manual 4afe, and the temp needle lives at half way... only ever moved once when i towed the motor bike trailor... but has never crept up at all ...

[clubby2084]

I had a similar problem with my 4AC. Temp gauge was around half way, sometimes higher. But I knew the car was not overheating.

I replaced the temperature sensor. This is what tells the dash gauge how hot the engine is. It was faulty and was giving a false reading.

Cost me about $20 or $25 from Repco. Problem solved. Temp gauge now sits around the quarter mark.

Edited September 30, 2010 by clubby2084

[idw]

half way up the temp gauge is fine, mine only gets higher than that when I'm letting it climb up the 4wd tracks to go mountainbiking.

 

the only cooling issues mechanicly i've come across is the relay for the thermo fan keeps dieing, I'm yet to find out why. you only really need to worry if the gauge gets to the red about 80% of the way up the dial.

 

EDIT: i let it climb up the tracks it doesnt always decide to go tho. :P

Edited October 1, 2010 by idw

[Womble1972]

Thank you all.

Flushed the heater core on the weekend, (orange rust again but it flows)

I bled the system as well using the gutter to get on a angle.

Done 500kms in it over the last 3 days No problems.

Guess i am paranoid

Thank you all for your help

Rod

[Trev]

Didn't notice this thread, the fwd 4a water system flows in at the top and out at the bottom not like the rwd system Dave posted, to flush mine out I do the following:

 

1. Turn cabin temp to hot.

2. Undo drain cock.

3. Pull the heater hose off of the top of the thermostat housing.

4. Insert hose into heater hose and turn on.

5. Let the water run out of the heater pipe until clear.

6. Once the water is running clean use your finger to block the heater pipe on the thermostat housing so the water backflows through the engine.

7. Once the water from the drain cock is running clear turn the tap on a steady rate so that the water fills the raditor and over flowa.

8. Do up the drain cock and with the water running quickly pull the hose out of the heater hose and put it on the heater pipe to minimise the air bleeding period.

9. Doing this should of leaked enough water out for you to add a concentrated coolant to the system.

 

Edit:

 

Should add the bleeding cycle.

 

10. With the cap off and the cabin temp set to hot run the engine until both radiator hoses and both heater hoses (if applicable) are around the same temp, keep an eye on the water level while doing this.

Edited October 5, 2010 by Trev

[altezzaclub]

the fwd 4a water system flows in at the top and out at the bottom not like the rwd system Dave posted,

 

Isn't that normal Trev?? Hot water goes in the top, gets cooled as it flows down and cool water exits the bottom back into the motor. Its just that FWD flow sideways don't they??

 

If your bottom hose is NOT a lot cooler than the top then your radiator is not working!

[Trev]

Isn't that normal Trev?? Hot water goes in the top, gets cooled as it flows down and cool water exits the bottom back into the motor. Its just that FWD flow sideways don't they??

 

If your bottom hose is NOT a lot cooler than the top then your radiator is not working!

 

No, I was talking about the engine, the radiator is out at the top and in at the bottom so the bottom hose will be hotter.

 

With the 4a system, the engine brings in water at the top, heats it up and sends it out at the bottom.

 

The AE8/9 series is a up/down radiator.

[Hiro Protagonist]

No, I was talking about the engine, the radiator is out at the top and in at the bottom so the bottom hose will be hotter.

 

With the 4a system, the engine brings in water at the top, heats it up and sends it out at the bottom.

 

The AE8/9 series is a up/down radiator.

?/

 

Doesn't make any sense. Vertical-flow radiators always flow top-to-bottom (which is why trans coolers etc sit in the bottom tank, otherwise there'd be no temperature differential and thus no cooling as it'd be essentially running in coolant the same temp as the trans fluid). Yes there are differences in layout between the FWD and RWD 4AGE systems, but both have the thermostat on the outlet of the radiator before going into the water pump (the little bypass valve on the thermostat is there to stop the water-pump cavitating). Both the EPGs for the AE86 and AE82 list the lower hose as radiator outlet, and the water outlet from the block above the water pump going to the top radiator hose.

Edited October 6, 2010 by Hiro Protagonist

[Trev]

?/

 

Doesn't make any sense. Vertical-flow radiators always flow top-to-bottom (which is why trans coolers etc sit in the bottom tank, otherwise there'd be no temperature differential and thus no cooling as it'd be essentially running in coolant the same temp as the trans fluid). Yes there are differences in layout between the FWD and RWD 4AGE systems, but both have the thermostat on the outlet of the radiator before going into the water pump (the little bypass valve on the thermostat is there to stop the water-pump cavitating). Both the EPGs for the AE86 and AE82 list the lower hose as radiator outlet, and the water outlet from the block above the water pump going to the top radiator hose.

 

Explain why the bottom hose is always the hottest and why the thermo fan switch opens when the water is released from the thermostat which is between the thermostat and radiator.

 

It is not a commodore Ian.