What tool to take apart the fan clutch actuator on 923a2?

[Swamp Donkey]

The part you see with the hole in the middle is a hollow cap. It pulls out. Take a sharp pick and grab that raised edge around the outside of the cap. Work one side and then the other back and forth. I had made a tool for pulling these out of some snap ring pliers with modified tips. Take your time with the pick. Don't use that center hole for prying. Some of the surfaces you will run into on the inside are sealing surfaces that don't need to be scarred.

I'd definately eliminate the filter. That looks like a fairly new shutterstat, unless you cleaned it up really well.

 

[TexAndy]

Horton thermal switch costs around $60. Solenoids are on Ebay for around 50 to $75. Requires a single power wire under the hood thru the thermal switch to the solenoid and that's it.
https://www.steelsoldiers.com/misc.php?do=showattachments&t=169313

Pretty slick. How long have you been running with that? I might look into that at some point.

 

[simp5782]

Pretty slick. How long have you been running with that? I might look into that at some point.

Since 2017 over 150k miles. One solenoid failure so far. They overnighted me one the next day since 24v isnt common

 

[TexAndy]

Since 2017 over 150k miles. One solenoid failure so far. They overnighted me one the next day since 24v isnt common

You've driven your 5 ton 150,000 miles in TWO YEARS? Good grief. What do you use your truck for, if you don't mind me asking?

 

[simp5782]

You've driven your 5 ton 150,000 miles in TWO YEARS? Good grief. What do you use your truck for, if you don't mind me asking?

Recover trucks that i or other friends buy or for other members. Yes. Sometimes my truck sees 8000 mi in a month it just depends.

https://www.steelsoldiers.com/showthread.php?162662-M923A1-30-000mile-OTR-Report&highlight=

 

[M35A2-AZ]

That is what I use on my trucks with AC, that way the AC unit can turn the truck fan on.

 

[TexAndy]

Well, the good news is that the clutch works. I fired the engine up and just ran shop air to the line going to the clutch and the cutch happily spun right up when I pressed the trigger on the air blower.

The bad news is, the shutterstat appears to be stuck. I replaced that "filter" output elbow with a new, unfiltered elbow and put it back on the truck. No dice. The shutterstat is not letting air pass.

So I'll probably just go with the electric air solenoid option rather than get another shutterstat. Unless there's a good reason not to. These shutterstats seem to be a common failure mode.

 

[TexAndy]

So if I understand this correctly I need:

1. A thermal switch that is Normally Open, circuit closes when temp reaches 200F so that it sends a signal to

2. A solenoid air valve with the valve portion Normally Closed that will then open when the solenoid coil is energized, allowing air to go to the clutch

Is that correct?

 

[simp5782]

So if I understand this correctly I need:

1. A thermal switch that is Normally Open, circuit closes when temp reaches 200F so that it sends a signal to

2. A solenoid air valve with the valve portion Normally Closed that will then open when the solenoid coil is energized, allowing air to go to the clutch

Is that correct?

Normally closed is for a fan that does not take air to engage it. Taking air away from it allows the fan to come on. Meaning the solenoid is always energized and when it hits its temp the circuit in the thermal is closed and the solenoid is deactivate and the fan clutch comes on.

 

[TexAndy]

Normally closed is for a fan that does not take air to engage it. Taking air away from it allows the fan to come on. Meaning the solenoid is always energized and when it hits its temp the circuit in the thermal is closed and the solenoid is deactivate and the fan clutch comes on.

Do you have a part number for the solenoid valve you bought?

 

[simp5782]

I sent it to your PM. It was on Ebay. They only had 1 left

Horton 993294 on Ebay. Or search Horton 24v. It did have the thermal switch with it. They are another 60 or so on Ebay. Just figure out what temp you want

 

[TexAndy]

Looks like that horton solenoid valve can be run as normally open or normally closed, depending on which input port you choose for the air.

 

[simp5782]

Looks like that horton solenoid valve can be run as normally open or normally closed, depending on which input port you choose for the air.

The solenoid works either way. The thermal switch is what does the control. they are listed as NO or NC

 

[Floridianson]

Here is a older thread and the funny looking filter inside the elbow is a filter. Myself I would clean it.
https://www.steelsoldiers.com/showthread.php?143231-92-shutterstat-fan-clutch-actuator

 

[Jbulach]

So if I understand this correctly I need:

1. A thermal switch that is Normally Open, circuit closes when temp reaches 200F so that it sends a signal to

2. A solenoid air valve with the valve portion Normally Closed that will then open when the solenoid coil is energized, allowing air to go to the clutch

Is that correct?

Sounds right.

I found an ebay deal that I couldn’t pass up on a Horton 993655, 205F on, 198F off. I also found a cheap ALLENAIR 3CBX8B-Y Solenoid Valve 24V-DC 1/8IN NPT D622649.
I still haven’t installed them yet tough to verify operation...

 

[Jbulach]

I had to beat my shutterstat upside down on a block of wood to get the piston out. If your seal is still in good shape, clean everything up good, your paintball gun oil should work, but as said go very light with it.