Fan clutch solves overheating

[landtank]

For those who might have missed a few threads that I've posted to I'll recap my situation.

First, I have a modified temp sensor in my truck done according to RavenTai's instructions so the is no dead spot and the beginning of the red area is around 220* so it is more sensitive than a stock gauge.

The truck through the winter months ran beautifully with the needle always at the midpoint of the gauge. If it fluctuated it was only barely noticeable.

In April I decided to swap out the tranny and this took me about 6 weeks to do with other projects and part orders interfering with steady progress.

On the first drive out when the swap was done the truck immediately started to run hot. It was @ 80*F and the needle was well above the 3/4 mark just driving around town.

A few days later I towed a 4k camping trailer for 2 hours up through some mountains to VT in 82* weather and buried the needle in the RED on the climbs but it would come down some on the flats. Again this is a modified gauge so while it was hot it's around 230* I think.

At this point I was wrestling with whether or not it was do to the mod in the temp gauge being sensitive to a normal condition or a real problem. A stock gauge at this point would only barely show some movement in the needle.

While in VT I swapped out the T-stat for an aftermarket Stant . The drive home was more of the same but less higher temps as it was more down hill.

Figuring that the load had something to do with it I took the truck out on that Sunday which was 100* here. The truck ran almost identical to the day before. Once the truck got to a certain temp it would just hang there and only go down if I pulled over and let it idle.

At this point it was about a needles width below the red and the AC was fully functioning. I mention this because I was probably @ 210* and the stock gauge would still indicate ideal engine temps and with the AC running the driver would be unaware of what he was putting his engine through.

At this point I was still wrestling with the idea of a bad tranny as the 3 core radiator, fan clutch and now the t-stat where all recently replaced. I finally had a clear moment in thought and realised that the fan was not engaging at these high temps. It has been said before to look for a Roar at start up, which I had, but this fan wasn't engaging at high temps.

I ordered an Imperial clutch from Advanced Auto parts. It turned out to be a Hayden unit. I installed it today and took the truck over the exact route I did on Sunday but today the temp was 80*.

The truck now seems to be more inclined to run at a 1/2 needle width above horizontal. Remember it does have the Stant stat in there so I can't say for sure why it is slightly higher.

During the drive it only budged from that spot on the occasions that I quickly altered my speed. One such time was coming at the end of the ramp off of the highway. I now was on secondary roads and there was about a needle width spike for a half a minute or so and then returned to normal. The other time was getting on the highway where I was pulling up to speed with the TC unlocked. For both these times it was at most a needle width in movement. Around town it didn't seem to move at all.

From an observation that ToolsRus has made about the Hayden clutch being a monster in size I check out the 2 and it is 50% heavier than the Imperial. I currently have one on order with PartsAmerica and will be ordering a new OEM t-stat to replace both and see what the truck performs then.

It was only a quick drive today but I'm feeling good about the truck. Unfortunately a cool front is coming ion this weekend and more testing in hot weather will have to wait.

My recommendations would be to MOD that temp gauge. It will not show a bad Fan clutch.

Once modded if it looks like it's running hot it probably is and is most likely the Fan Clutch. Replace it with what you want, but I don't see me using an OEM again anytime soon.

[RavenTai]

Thanks for the report, let us know how it does in hot weather, this time of year should not be a long wait.

can you get pics of the two clutches to help us identify the light duty vs the heavy duty clutches?

[landtank]

Originally Posted by RavenTai

Thanks for the report, let us know how it does in hot weather, this time of year should not be a long wait.

can you get pics of the two clutches to help us identify the light duty vs the heavy duty clutches?

Expected arrival of the Hayden clutch is July 4th, so it will be a few weeks.

[Tools R Us]

Glad the clutch fixed it up, Rick!

If your clutch was just replaced I would have a "come to Jesus" talk with Dan about Toyota parts warranty?

From a quick surf of the Hayden site they make a severe duty clutch, from the drawing it looks a lot like a blue hub. This comment looks interesting "multiple viscosity silicone".
http://www.haydenauto.com/severeduty.htm

[Tools R Us]

From their FAQ they make three grades of clutches, their catalog page is down right now, so don't know if they are all available for the LC?

Q. What is the difference between a standard, heavy and severe duty fan clutch?
A. Each fan clutch type is designed to simulate the performance of the original equipment clutch that it replaces. All fan clutches are for specific applications and should be applied only on the application for which they are cataloged.

* Standard Duty Thermal
Turns the fan 50-60% of shaft speed when engaged. Used with fans with lighter pitch fans. (1-1/2" of pitch) Flat plate impeller design with 30 Sq. In. of working surface.
* Heavy-Duty Thermal
Turns the fan 80-90% of the shaft speed when engaged for increased cooling. Used with deeper pitch fans. (2 1/2" of pitch). Land and groove design with 47 Sq. In. of working area allows higher operating RPM's.
* Severe Duty Thermal
Turns the fan 80-90% of the shaft speed when engaged. Used with deeper pitch fans. (2- 1/2" of pitch). Land and groove design with 65 Sq. In. of working area. Larger working surface provides cooler running and longer life expectancy.

[Cruisin'Carolina]

Good info....thanks for the detail.

[landtank]

I honestly don't see me calling Dan on this one. First, I can't say for sure when I bought it and considering how much the man has $aved me it would just be bad Ju-Ju to ask for something. Besides shit happens.

I went through the Hayden site catalogue and they only have one clutch listed for the LC and no mention as far as it's "duty".

I'll take comparison pics of all three when I have them side by side.

[MLX450]

Do you get the infamous "ROAR" upon start up with the new hayden unit?

[cary]

Out of curiosity, can you hear the Hayden when you are driving around town? I can barely hear the Blue one when it starts to get hot, it cuts in but there is no huge fan noise.

[-Spike-]

Did you look at the Stant and compare it to the stock thermostat? I did, and wasn't impressed. I totally understand the thought behind changing things out to diagnose a problem, but if I were you I'd be re-evaluating that move.
I'm sure the Stant won't blow your motor next week, but the design of the OEM part looks to be superior, and higher flow when opened.

-Spike

[landtank]

Originally Posted by MLX450

Do you get the infamous "ROAR" upon start up with the new hayden unit?

Yes it is there also

Originally Posted by cary

Out of curiosity, can you hear the Hayden when you are driving around town? I can barely hear the Blue one when it starts to get hot, it cuts in but there is no huge fan noise.

I never noticed it but wasn't listening for it either.

Originally Posted by -Spike-

Did you look at the Stant and compare it to the stock thermostat? I did, and wasn't impressed. I totally understand the thought behind changing things out to diagnose a problem, but if I were you I'd be re-evaluating that move.
I'm sure the Stant won't blow your motor next week, but the design of the OEM part looks to be superior, and higher flow when opened.

-Spike

I'm ordering a new OEM today. I'm planning on changing that and going with the Hayden clutch when I have both in hand.

[RCFloyd]

A couple of questions guys...

1. As far as the Hayden Fan Clutch; if it is in '50% Heavier' than the Imperial and/or OEM unit, doesn't that mean more mass for our motors to push (power loss/fuel consumption)? And, does bigger mean better? I need a new one so I'm really following this thread.

2. I recently did the Radiator Flush/Coolant Exchange, and while I was at it, swapped out the T-Stat. I used a Stant. I did see the obvious difference in build quality, but I figured that there are millions of these things being used, and that it must function just fine.
How many others out there running these? Any problems?

I thought that I could report back as to what Temp. the Stant was rated for (180 or 195), but apparently I threw the box out.
Upon reading up on the necessity of modern motors running at their proper temp. (hot), I'm going to call the parts store to find out what I've got, and if it's not the 195, I'll replace it w/OEM.

Robert

[landtank]

The stant I got was 180*. Personally I could care less about power loss and fuel economy if it means better cooling for the engine.

Another side note here, I've noticed higher idling oil pressure as well since the new fan clutch. I think the oil was thinning out quite a bit during the higher temps as the needle barely registered on the guage at idle back then.

[MLX450]

I see it now! Bad Fan Clutch = Higher engine temps = PHH = A/C cutting out = HG = Aluminum Radiator exploding = Lower oil pressure ...... Wait a minute ...... lol

[landtank]

Originally Posted by MLX450

I see it now! Bad Fan Clutch = Higher engine temps = PHH = A/C cutting out = HG = Aluminum Radiator exploding = Lower oil pressure ...... Wait a minute ...... lol

Laugh all you want, but this could be the root of all that is evil with heat related failures on our trucks.

[-Spike-]

Originally Posted by landtank

Laugh all you want, but this could be the root of all that is evil with heat related failures on our trucks.

For RCFloyd's benefit: this is why I question the Stant. A couple of degrees hotter for thousands of miles may or may not hurt the motor. Heat spikes from water trapped in the block too long may or may not hurt the motor. Settling sediment or some other rediculous-sounding outcome from lowered flow rates may or may not... A crappy bypass valve may or may not... etc.

The Stant product looks like it was engineered to do the job, not excell at it. The OEM thermostat looks to be overengineered. I'm not very anal when it comes to maintenance on my vehicles, but when I replace something- especially a critical something- I tend to lean toward the cautious side. I'm not prejudiced either- if the Stant looked better, it would be in my truck.

-Spike

[MLX450]

That's what i mean ..... The source ..... and the aftermath ......

[landtank]

I wonder if other "more extreme enviroment" markets gets a different clutch than here in the states?

Anyone from Africa, Australia or Suadi Arabia care to check for us?

[RCFloyd]

OK, I checked with the Parts guy, and I did indeed get the 180 degree Stant. That should answer CDans query in the above post.

Also, I will be getting the OEM T-stat, but not because of the supposed build quality issue, but rather because of the correct heat range that it gives (195). I mean, Stant is the largest manufacturer in the world of these things, so even though it looks chinzy, I'm quite sure that it does it's job just fine...

What I'm more interested in though, is this issue of the weight/mass of the Hayden Fan Clutch's vs. the OEM/Imperial, and what that means for power/fuel economy. Anyone?

Robert

[landtank]

I thought the OEM was 82*C which is 179.6*F.

[-Spike-]

Originally Posted by RCFloyd

Stant is the largest manufacturer in the world of these things, so even though it looks chinzy, I'm quite sure that it does it's job just fine...

Fram is probably the largest oil filter brand in the world, or damn close. Ask around how their product stacks up.

-Spike

[RCFloyd]

Apples and Oranges Spike. I'm no expert on T-Stat's either, but it's not a good analogy.

Rob

[Tools R Us]

Originally Posted by cary

Out of curiosity, can you hear the Hayden when you are driving around town? I can barely hear the Blue one when it starts to get hot, it cuts in but there is no huge fan noise.

In the cruder designed clutches the valve is either full on or off, or a couple of steps, when they are "on" you will hear them. The blue hub has a stepless progressive valve, the valve will open or close slightly as needed to maintain an even air flow temp and may never be fully "on" unless needed. This would seam to be better than a setup that senses heat, turns on full blast, clicks off, repeat, making a stepped heat profile?

[-Spike-]

Originally Posted by RCFloyd

Apples and Oranges Spike. I'm no expert on T-Stat's either, but it's not a good analogy.

Rob

Ok. Not sure why, but I guess it doesn't matter. Two products that are very well known, one of which isn't nearly as good as most people think it is. The other, I have no idea, I just know that it looks crappy. Probably works fine for X# miles, what if I forget to change it then? I'll take the one that looks as if it were designed better, if that's all I have to go by.

-Spike

Edit to add: I've Googled 'Stant thermostat problems' and found... none.

-S

[Bear80]

Well I'll just say that we unknowingly put a Hayden unit from Advanced Auto on my sisters about a year ago. When I had it at my house working on the birfields and a/c amongst other things, I did noticed that it "roared" much more and seemed to pull more air then the stock unit on mine. I was leery about using a non-oem part, but looks like we did one better and didn't even know it.

[alia176]

I swapped out the 150k fan clutch with a new OEM clutch and immediately noticed the "roaring" sound. The OEM unit was prolly dying a slow death and that's why I didn't notice the "roaring" sound on startup.

[landtank]

As I understand it the roaring sound on startup is from the fluid with in the clutch being cold, so it's thicker and transmits drive to the fan.

During this initial startup the oil begins to warn and thin out to where the valve can control drive to the fan.

If you get no roar on startup there is an issue with the oil as not having enough or it has broken down from use.

Since my fan roared on startup, I suspect there was enough oil but something with the valve was bad. I checked the temp spring on the outside and it was clean and intact. Once I'm comfortable with my truck running in hot weather I'll probably tear down the OEM clutch to see what is going on in there.

[Tools R Us]

Originally Posted by landtank

As I understand it the roaring sound on startup is from the fluid with in the clutch being cold, so it's thicker and transmits drive to the fan.

During this initial startup the oil begins to warn and thin out to where the valve can control drive to the fan...

The roaring is from the oil leaking out of the reservoir into the active part of the clutch when sitting. Some designs leak more than others. The oil works better, is capable of transferring more power when warm.