Overheating and whining noise.

[Rebel_way]

Hi there!

Hope you guys not having any problems with your 4runners, but I do:yo:
So the current two things that are worrying me are overheating and some intermittent whining noise.

The overheating. It started recently, I noticed the engine normal operating temp is a bit higher than it used to be. I didn't think of it much, since i was in town and had no idea how quick it can be moving towards overheating when I go to forest roads and turn my 4x4 and low gears on. So right now when I go under load it overheats rather quickly and I have to stop to cool it down, it cools down pretty quickly especially when I turn cab heat on.
There was a thing happened like 4k ago. My cooling system opened while going up some forest road (one of the rear heater core bypass coupling failed), I have lost a great deal of coolant. I had some spare coolant, but not enough so I mixed it with water and turned around. on my way back I was overheating a few times but would stop before it get to red and cool down again. Made it to the parts store and got some coolant and added it to my expansion tank, I was loosing some coolant on the way because I had to reconnect my rear heater core to close off the cooling system, but the RHC lines were a bit leaky and I kept adding proper coolant as I proceeded home.
At home I flushed the system, filled new proper coolant and bypassed RHC again.
I have no idea if my system burst and current overheating are related, but Im looking for ideas on where to start chasing a problem.
Not loosing any coolant,coolant as red as toyota coolant can be,oil cap doesn't have any white under it, water pump was replaced 17k ago, hoses like 2 y.o., cap is under a year, radiator like 5y.o., fresh coolant. Have no idea if t-stat was ever replaced. need help and ideas.
Sorry for too many letters

Another thing is whining.
It would come up from nowhere. Cant make it to whine at will.
Sometimes it whines a bit at start, start moving it continues for a bit or goes away, today run an engine while parked and was given it a gas it would whine louder with higher rpms, foot off gas, whining going down but still it will continue in the background. One day it would start whining when going up the hill on 4x4 low, stopped, turned into 4x4 high and whining would stop. Later in the day whining come up from nowhere on a straight trail, i stopped, popped the hood, whining was coming from steering pump/ AC compressor side, moved steering wheel back and forth...nothing happened to the whining, played with AC on/off and whining stopped. turned AC on no whining, turned AC off..no whining. Went home, no whining for few days. Replaced AC belt tensioner and it didn't affect whining in any way. belts and timing belt were replaced like 17K ago.
Whining comes and goes. Need help chasing a problem.

Thank you so much guys.
Im sorry if it looks like waaay to many letters.

 

[jgue467]

I say the fan clutch is not doing its job correctly, especially at low speeds, I'd replace it.

Also check the space between a/c condensor and radiator, i offroad sometimes thru tall thin grass, it manages to get between the two, sometimes filling it half way or more from bottom up, have to take front skid off to look up between them and use a narrow stick to clear out.

Whining could be alternator, not experience there, maybe some one else while chime in....Luck! :cowboy:

 

[Rebel_way]

I say the fan clutch is not doing its job correctly, especially at low speeds, I'd replace it.

Also check the space between a/c condensor and radiator, i offroad sometimes thru tall thin grass, it manages to get between the two, sometimes filling it half way or more from bottom up, have to take front skid off to look up between them and use a narrow stick to clear out.

Whining could be alternator, not experience there, maybe some one else while chime in....Luck! :cowboy:

Thank you for the comment.
Fan clutch looks good, just checked. There is also no garbage between AC condenser and the rad. Washed my rad nicely few weeks ago with the hose lots of dust came out, but it haven affected the overheating issue.
Alternator was replaced few years back, and the noise was coming from ac compressor side.

 

[spartacus]

If you overheated the motor wouldn't hurt to do a compression test and a leak down test to eliminate head gaskit or cracked cylinder heads.

 

[Rebel_way]

So I have a Bluetooth scanner and I hooked it up to see my coolant temp while I'm driving and it is like 89-95C
Drops to 89-90 when driving on hwy and goes up to 95 when standing in traffic in the sun.
On the way back I turned on my AC and was standing on the intersection waiting for my light and suddenly noticed that my temp is all the way up to 106C (my temp gauge don't move a bit)!! So it was a slow traffic for a few blocks and it went up that high! With AC on hwy it was at 95C.
I came to a stop and turned my engine off and started it again and the whining noise came up, the one I was having the problem with. I did a video and I will post it later. Temp was still at around 105C and started to drop down. Played with the throttle and as rev went up the whining became louder. Turning wheels back and forth didn't affect the noise and turning AC on/off didn't affect anything. Turned engine off and turned it on...noise gone, started engine again...same thing no noise.

 

[Rebel_way]

If you overheated the motor wouldn't hurt to do a compression test and a leak down test to eliminate head gaskit or cracked cylinder heads.

I make sense to do it, but haven't got around doing it. I don't have any loss of power or coolant disappear, or white smoke. But I did found some loose hose from front heater core that is oozing some coolant.

 

[Rebel_way]

Toyota 4runner 98 V6. Whinging noise, looking for solutions. - YouTube
Ok. This is the video of my problem.

 

[jgue467]

...89-95C
Drops to 89-90 when driving on hwy and goes up to 95... is all the way up to 106C (my temp gauge don't move a bit)!! So it was a slow traffic for a few blocks and it went up that high! With AC on hwy it was at 95C....

Should Always be 90C or less. Unless stop/go and/or towing/hills but even then mine never goes over 93C. Never, Ever should hit 106 C!!

Don't ever count on dash temp, it won't even budge from 9 0'clock position until over 135 C.

Either not enough water is flowing, not enough air or both.

BTW - how did you test the fan clutch?

 

[Rebel_way]

Should Always be 90C or less. Unless stop/go and/or towing/hills but even then mine never goes over 93C. Never, Ever should hit 106 C!!

Don't ever count on dash temp, it won't even budge from 9 0'clock position until over 135 C.

Either not enough water is flowing, not enough air or both.

BTW - how did you test the fan clutch?

I did notice that my water temp is a bit higher, like it always been a bit lower, but once I started to have overheating issues I noticed that engine is always running a bit hotter, so I will be doing my thermostat today.
There was a video on YouTube about a fun clutch and how good one spins if you try to spin it manually. Mine only does 1/8 of the turn +/- if you try to spin it.

What do you think about the whining? Can it be water pump? It is under 20k miles.

 

[Bad Luck]

I did notice that my water temp is a bit higher, like it always been a bit lower, but once I started to have overheating issues I noticed that engine is always running a bit hotter, so I will be doing my thermostat today.
There was a video on YouTube about a fun clutch and how good one spins if you try to spin it manually. Mine only does 1/8 of the turn +/- if you try to spin it.

What do you think about the whining? Can it be water pump? It is under 20k miles.

For the whining noise I would recommend pulling off the accessory drive belts and see if the noise goes away

 

[Wikano]

I think the AC compressor sliding mechanism has something lodged in it or needs some lube. A while back my AC had some noise issues and would drain engine power when on. So I thought "must be a bad bearing" and got a new bearing only to open it up (which was not easy) to find that there was rust in the "slip joint" that would cause the AC "plunger" when magnetized would bind and cause drag. So I just gave it a good scrubbing to remove the rust and put some moly lube and it had been happy ever since, no need to replace the original bearing with 350k on it.