Heat problems

[FratRunner3rdGen]

Hello everyone,
I have a 97 4Runner that was my fathers since 1997. It's a been a great truck and hasn't had many problems and it only has 141k miles on it. However, the past couple of days when I have the truck on and in park, after awhile the temp needle starts to go all the way up from where it usually is (slightly lower than or at the halfway point). I noticed it just sitting in it between classes. And it goes back to normal when I start driving again.
Sorry if this has already been discussed I am rather new to here since I only recently became truly aware of how awesome 4Runners really are. I also am not very mechanically savvy though it is something that I really enjoy and I find myself wanting to learn more and more about. This is only my first post so please pardon my ignorance and really long post haha.

Thanks in advance!

 

[TheDurk]

Hello everyone,
I have a 97 4Runner that was my fathers since 1997. It's a been a great truck and hasn't had many problems and it only has 141k miles on it. However, the past couple of days when I have the truck on and in park, after awhile the temp needle starts to go all the way up from where it usually is (slightly lower than or at the halfway point). I noticed it just sitting in it between classes. And it goes back to normal when I start driving again.
Sorry if this has already been discussed I am rather new to here since I only recently became truly aware of how awesome 4Runners really are. I also am not very mechanically savvy though it is something that I really enjoy and I find myself wanting to learn more and more about. This is only my first post so please pardon my ignorance and really long post haha.

Thanks in advance!

Overheats when stopped and cools off at speed usually means fan clutch. The factory ones are dying as our trucks reach their teens.

From a BMW board but applies to our trucks as well:

If you have reason to suspect that the fan clutch is defective, here is the recommended procedure to verify the condition of the fan clutch.
1. Start the car (cold) with the hood open and note if the fan is turning, increase the engine RPM and note if the fan turns faster and the noise increases, if it does, first good indication, if it does not increase speed/noise, clutch is bad and needs to be replaced. (Remember, this must be tested after the car has been off for an extended period, over night etc.)
2. Leave engine running and note if the fan starts to slow down after 2-5 minutes, speed/noise should diminish and even raising the RPM, the fan should not make as much noise as when first starting, if it does slow, this is the second good indication. If speed/noise does not decrease, clutch may be “frozen” and should be replaced.
3. Leave the engine idle and watch the temperature indicator. When normal operating temperature has been reached, some increase in fan speed/noise should be noted, in particular when the RPM is increased. If temperature is fairly stable and the fan noise/speed increases or cycles, third good indication. If temperature indication continues to increase, with no increase in fan noise/speed, clutch is defective and should be replaced.
4. After the engine is at normal operating temperature or above, is the only time that the “rolled up newspaper” test that many people talk about should be performed! Take some newspaper and roll it up into a long narrow tube. Be careful, keep hands and fingers away from the fan while performing this test! With the engine at full operating temperature and idling, take the rolled up paper and insert it on the back side of the fan and try to reach the hub of the fan avoiding the blades until close to the hub. Push the rolled paper at the fan increasing the friction to the hub area of the fan. If the fan can not be stopped easily this is the fourth good indication, if it can be stopped the clutch is defective and should be replaced. Again, this test can only be performed when the engine is at or above full operating temperature.

Testing can be performed in any order but just make sure the conditions during testing are those that are specified for that specific test. Do not continue to operate the engine if the temperature continues to rise and certainly stop if the temperature approaches “redline”.

 

[FratRunner3rdGen]

Hey thanks TheDurk, appreciate the help. I'll check it out later tonight when I get a chance.

 

[FratRunner3rdGen]

Overheats when stopped and cools off at speed usually means fan clutch. The factory ones are dying as our trucks reach their teens.

From a BMW board but applies to our trucks as well:

Another quick question my friend asked me to drive him to pick up his car so I figured I'd ask about my truck. And I also later called a mechanic friend and both asked if the fan is mechanical or electric. Pretty sure it is mechanical but I could sef be wrong. Also said it could be the water pump but just wondering if you knew whether it was mechanical or electrical?

 

[TheDurk]

Another quick question my friend asked me to drive him to pick up his car so I figured I'd ask about my truck. And I also later called a mechanic friend and both asked if the fan is mechanical or electric. Pretty sure it is mechanical but I could sef be wrong. Also said it could be the water pump but just wondering if you knew whether it was mechanical or electrical?

Unless it has been modified by your father, it is mechanical. What I posted only applies to mechanical fans with fluid fan clutches as are found on all 3G 4Runners from the factory.

 

[FratRunner3rdGen]

Hey figured I'd respond since i got it fixed. sorry it took so long just havent really been on here much for awhile. I took it in to get fixed turns out fan clutch was fine just that my radiator was leaking because the skid plate was rubbing against it. (I skidded on some black ice and hopped a curb and something knocked it in) I just got the radiator replaced and banged out the skid so all is well.