Clutched Cooling Fan ?'s

[mrlocksmith]

Hi folks:

I just had my radiator, thermostat and all hoses replaced. Before the work was done you could really hear it when the clutched fan engaged, it made a dull roar sound. Now I hardly hear the fan and it runs hotter than before the swap while on the freeway (About at 1/2 instead of 1/4) Also when going up 10 miles of hills (Highway 17 here in the bay area) I was almost at red once I got to the top.

I checked the fan, it does not wobble but there is less resistance than I expected when the fan is hot, it is not that hard to turn.

How hard should the fan be to turn when hot?

Mark

 

[2mbb]

The high temperatures you are seeing could be an air bubble where the temperature sensor is. You need to "burb" the cooling system to get all the air out--do a search and you'll find out how. My fan clutch engages in the summer, but not so much in the winter, so your under hood temperatures may not be hot engough to engage the fan clutch, but because of an air bubble you think the engine is running hot.

If you have access to a thermometer, try to measure the coolant temperature to see if it really is hot.

 

[mrlocksmith]

It has been burped twice. I checked the thermostat housing temp with a pyrometer, it was at 188 with the temp gauge at about 1/3. I did not get a chance to use the pyrometer when it got close to red though. I'll have to heat up the motor again and check. I got a cheap IR BBQ meter online to use as a pyrometer. Works great.


Mark

 

[D'Animal]

It has been burped twice.

Mark

I was having similar problems. I read it here on MUD to open or Turn on all of your heaters, rear as well and burp it again.

Since I did this no more problems.

 

[mrlocksmith]

I may have negleted to open the heaters

Mark

 

[lovetoski]

I may have negleted to open the heaters

Mark

You wouldn't be the first. Open it up, reburp, the test. Repost with how it turns out. (Based on the other work you did, you should be good to go.)

 

[phoenixrider]

is there a way to test the operation of the clutch fan? to make sure it engages when it is supposed to? Mine did the same thing. Sometimes would work, other times not. I find it hard to believe that the engine temps can be right at redline and yet a working fan decides it's not 'hot enough' yet.

 

[2mbb]

This may be a wrong assessment, but the fan clutch is essentially measuring the temperature of air exiting the radiator. The temperature sensor however, measures themperature of the water as it is leaving the engine block/head. If, for example, the radiator is not working (e.g. it is severely clogged) then the air flowing through it may not get very hot, but the engine will. Or if the ambient air temperature is very cold, then the air temperature leaving the radiator may never get hot enouigh to engage the fan.

 

[phoenixrider]

guess that makes sense. Which also makes the aurgument that clutch fans are pretty worthless, then, unless they are operating under 'ideal' conditions.

Sounds like I should install a pusher fan in front, just in case. Don't want to smoke a 5k engine becuase of a 200 dollar part....

 

[hks3sgte]

A stock cooling system that is in GOOD working condition will not need an additional electric fan.

A TOYOTA fan clutch will be able to move enough air through an unclogged radiator to keep everything cool.

 

[jwest]

Hi folks:

I just had my radiator, thermostat and all hoses replaced. Before the work was done you could really hear it when the clutched fan engaged, it made a dull roar sound. Now I hardly hear the fan and it runs hotter than before the swap while on the freeway (About at 1/2 instead of 1/4) Also when going up 10 miles of hills (Highway 17 here in the bay area) I was almost at red once I got to the top.

I checked the fan, it does not wobble but there is less resistance than I expected when the fan is hot, it is not that hard to turn.

How hard should the fan be to turn when hot?

Mark

Not hearing the fan as before is a good indication that the clutch is not binding up enough. These are easily rebuildable and I suggest using a silicon fluid in the 6000 cst range.

.

 

[phoenixrider]

is there a thread on rebuilding the stock?

I bought an aftermarket cause I couldn't afford a new OEM, but I'd prefer the OEM

 

[cwb]

guess that makes sense. Which also makes the aurgument that clutch fans are pretty worthless, then, unless they are operating under 'ideal' conditions.

Sounds like I should install a pusher fan in front, just in case. Don't want to smoke a 5k engine becuase of a 200 dollar part....

No, you're wrong. A fan clutch isn't worthless at all. If everything is working even pretty well, you'll have no cooling issues. Change the fan clutch and I bet your problem will go away.

 

[Elbert]

radiator fan clutches work very well. There are thousands of various models vehicles with fan clutches the world over. They are not life-time parts and will need to be replaced over time or "rebuilt" if you choose to do so. If you have ever driven a car / truck with a flex fan or fixed fan (old school) you'll appreciate the design of a fan clutch. Remember your radiator shroud has to be in good shape for the fan to work as designed. I'm not a big fan of the OEM fan shroud, but there are not any options out there unless you fabricate one yourself or have it done. A good fan shroud is key to the fan's performance.

 

[mrlocksmith]

Status of Cooling Issues:

1) Flushed the coolant system twice with Prestone Super Flush and the T-Insert installed on the heater hose.
2) Replaced the T-Stat & Gaskets (In case I had one that did not open all the way)
3) Installed a spring in the lower rad hose
4) Installed a Mechanical Temp Guage
5) New water Pump
6) New Fan Clutch

On the flat in 80'F weather on the freeway or on surface streets I run about 195-200, On mild hills it gets to about 210, On long 5-8% grades (Like going over the Sirras from Sacramento to Reno) it gets hot still 220-230 when I turned on both heaters it ran at 205F up the hills.

Keep in mind my rig is loaded with a Roof Top Tent, ARB Bumpers, Dual Batts, Cabinets and gear. I have not taken it to truck scale yet but she is not light that is for sure and that may be the contributing factor in how hot it runs. I will be dong a leak down test to see if there is a head gasket issue or a clogged cat.

Mark

 

[rchalmers3]

This might sound silly, but more than a few times I found that on some vehicles that were running hotter than normal for no apparent reason, I needed to determine if they had too much antifreeze in the cooling system.

Restoring the coolant mixture back to 50/50 or less allowed the liquid to do it's job of soaking heat from the engine.

I guess the ethlene glycol is a barrier to heat extraction and more is not always better.

Hope this helps,

Rick

 

[Aseif007]

Did you install the gaskets correctly on the t-stat? Also, my buddy that works at Santa Cruz Toyota had this trick funnel for filling the radiator and the funnel clipped on the opening of the radiator, then you filled it until the water will not go into the radiator and the funnel was full. Then he started my Tacoma (in this case) and as the t-stat opened up the level in the funnel went down and we kept adding water until normal operating temps were reached. (we did turn on the heat inside as well) Then we burped the upper radiator hose and when it was full you put this stopper into the hole of the funnel and pull it off the radiator with the excess water still in it. Then pull of the funnel cap, and put on the radiator cap. Or you can burp it, it takes a long time sometimes so don't be discouraged. I am close by if you need some help.

Status of Cooling Issues:

1) Flushed the coolant system twice with Prestone Super Flush and the T-Insert installed on the heater hose.
2) Replaced the T-Stat & Gaskets (In case I had one that did not open all the way)
3) Installed a spring in the lower rad hose
4) Installed a Mechanical Temp Guage
5) New water Pump
6) New Fan Clutch

On the flat in 80'F weather on the freeway or on surface streets I run about 195-200, On mild hills it gets to about 210, On long 5-8% grades (Like going over the Sirras from Sacramento to Reno) it gets hot still 220-230 when I turned on both heaters it ran at 205F up the hills.

Keep in mind my rig is loaded with a Roof Top Tent, ARB Bumpers, Dual Batts, Cabinets and gear. I have not taken it to truck scale yet but she is not light that is for sure and that may be the contributing factor in how hot it runs. I will be dong a leak down test to see if there is a head gasket issue or a clogged cat.

Mark