Help identifying engine fan controller components

[planodp]

I'm getting the coach ready to head out to he North West to see the great American beauty. In a year when I finally call it quit! I know that I'll have to claim many 6-7% grade hill. I have been reading a lot on overheating like this post  https://www.monacoers.org/topic/2870-seeking-source-for-fan-control-for-hydraulic-fan/ . I ready don't know what kind of controller I have and any upgrade suggestion. Attached is what is currently installed on my 04 Executive 500 ISM. The bottom valve have 2 wire connector attach to it. Thank you!

[jacwjames]

The second picture is of a thermovalve.   http://www.nwrvsupply.com/product/553109857210.html

[Fonman]

You have the good (in my opinion) thermostatic wax valve along with an electric over ride which I believe is to run the fan when you have the AC on.

[waterskier_1]

As previously mentioned, you have the thermo wax valve.  I haven't heard of these failing much.  It seems it's the electronic fan speed controllers that are more problematic.  The electronic were supposed to be much better, taking input from the engine so it could anticipate that the temperature will rise (more throttle, for example) and turn the fan up BEFORE the radiator actually sensed an increase in temp.  It sounds good, but I'm not sure how well it really worked.  My 97 Dynasty C8.3 had a wax valve, as does my 05 Exec Detroit Diesel so I have no personal use experience.  I would not put that high on a spare parts list.  Even if it fails, it's designed to fail full speed, so you're not dead in the water.  Even if this didn't work, you can simply carry some brass plugs and remove the hydraulic lines from the wax valve, and plug the lines which will force the motor into full speed.

  -Rick N.

[planodp]

Thank you guys. I feel a lot better now. I'll carry a -6 coupler and cap. Again thank you 😊 

[Rick A]

40 minutes ago, waterskier_1 said:

As previously mentioned, you have the thermo wax valve.  I haven't heard of these failing much.  It seems it's the electronic fan speed controllers that are more problematic.  The electronic were supposed to be much better, taking input from the engine so it could anticipate that the temperature will rise (more throttle, for example) and turn the fan up BEFORE the radiator actually sensed an increase in temp.  It sounds good, but I'm not sure how well it really worked.  My 97 Dynasty C8.3 had a wax valve, as does my 05 Exec Detroit Diesel so I have no personal use experience.  I would not put that high on a spare parts list.  Even if it fails, it's designed to fail full speed, so you're not dead in the water.  Even if this didn't work, you can simply carry some brass plugs and remove the hydraulic lines from the wax valve, and plug the lines which will force the motor into full speed.

  -Rick N.

Question for Rick N, “Even if this didn't work, you can simply carry some brass plugs and remove the hydraulic lines from the wax valve, and plug the lines”

Would you need to plug off all 4 of hydraulic lines or can the actual pump itself just drain out? 
The questions a neophyte would ask.

Really?

Yup. 

 

 

Edited September 19, 2021 by Rick A

[waterskier_1]

44 minutes ago, Rick A said:

Question for Rick N, “Even if this didn't work, you can simply carry some brass plugs and remove the hydraulic lines from the wax valve, and plug the lines”

Would you need to plug off all 4 of hydraulic lines or can the actual pump itself just drain out? 
The questions a neophyte would ask.

Really?

Yup. 

 

 

No, you only plug the two lines going to the wax valve.  You leave all the other lines going to motor untouched.  The wax valve is in the "control circuit" of the pump.  The more fluid that flows through the wax valve, opening the bypass valve in the motor, allowing most of the hydraulic fluid to bypass the motor, resulting in lower fan speed.  On the other hand, plugging the line (2 plugs so the fluid doesn't flow out) will result in pressure increase to the bypass valve in the motor, applying all the hydraulic fluid to the motor thus increasing fan speed.

In either case, you are not letting any hydraulic fluid "out" (except for a tiny bit when you remove the connector from the wax valve and put the plug in).  You need the hydraulic lines to the fan motor and the power steering pump connected to the hydraulic pump.  This is only affecting the "control" of the fan motor.

 

[Rick A]

16 minutes ago, waterskier_1 said:

No, you only plug the two lines going to the wax valve.  You leave all the other lines going to motor untouched.  The wax valve is in the "control circuit" of the pump.  The more fluid that flows through the wax valve, opening the bypass valve in the motor, allowing most of the hydraulic fluid to bypass the motor, resulting in lower fan speed.  On the other hand, plugging the line (2 plugs so the fluid doesn't flow out) will result in pressure increase to the bypass valve in the motor, applying all the hydraulic fluid to the motor thus increasing fan speed.

In either case, you are not letting any hydraulic fluid "out" (except for a tiny bit when you remove the connector from the wax valve and put the plug in).  You need the hydraulic lines to the fan motor and the power steering pump connected to the hydraulic pump.  This is only affecting the "control" of the fan motor.

 

[Rick A]

Sorry I am a bit confused, like a said I'm a neophyte when it comes to this control system.

Summary

1. Remove pipes from the wax valve. 

2. Insert plugs, this is where the confusion is. Plug the Wax valve ports or the 2 pipes, one from the pump and the other to the fan motor?

3. The 2 pipes. 

• One has hydraulic fluid coming from the pump?
• The other goes to the fan motor? The fan will run as default - no pressure?
• Is this going to damage the fan motor if there is no fluid in them?

 Excuse my ignorance on this.

I just like to know what you guys are talking about.

 

Thanks for your time.

 

[waterskier_1]

18 hours ago, Rick A said:

Sorry I am a bit confused, like a said I'm a neophyte when it comes to this control system.

Summary

1. Remove pipes from the wax valve. 

2. Insert plugs, this is where the confusion is. Plug the Wax valve ports or the 2 pipes, one from the pump and the other to the fan motor?

3. The 2 pipes. 

• One has hydraulic fluid coming from the pump?
• The other goes to the fan motor? The fan will run as default - no pressure?
• Is this going to damage the fan motor if there is no fluid in them?

 Excuse my ignorance on this.

I just like to know what you guys are talking about.

 

Thanks for your time.

 

Here is a diagram of a typical hydraulic system.  This is not from Monaco, but representative.  The wax valve is not a on/off valve, it is a variable viscosity valve, that varies by temperature.  When "cold" the was is mostly solid (like a candle that isn't burning).  That solid prevents (or greatly limits) oil flow through the wax valve.  Low oil flow results in low fan speed.  As the temperature of the radiator increases, the wax becomes less viscous, allowing more oil to flow through the wax valve. As oil flow increases, fan speed increases.  You will NOT be draining any oil. The only oil loss will be from disconnecting the line from the wax valve and screwing the plug in.  Of course you will do this when the engine is not running.  Therefore the hydraulic pump is not running, and the system isn't under any pressure (except that exerted by gravity).  Note that these are just control lines, (Labeled E, F, & G which might not be present in your system, in the attached diagram).  These are NOT the main pump lines (in the diagram labeled H for the input to fan motor, and D for the output of the fan motor.  

[Rick A]

Thank you for going to such lengths to explain this. Thank you.

[planodp]

Thank you Rick N. That's a great explanation!

[Rick A]

I figure this advice will be a regular reference.