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Topic: Hydraulic fan controller DIY (Read 5333 times) previous topic - next topic

Re: Hydraulic fan controller DIY

Reply #20 –
I'm sure there is. I'll be looking into something
Scott

Re: Hydraulic fan controller DIY

Reply #21 –
Quote from: wolfe10 –
What was ambient temperature when the screen shot above showed 97 degrees F?

With 70 degree ambient temperature and driving 75 MPH and only seeing 97 degree intake temperature (assuming that is an accurate number) there HAS to be air flow through the CAC.

But, as you said, summer temperatures will be the biggest test.

Like your idea of fans to high anytime the retarder is on.  Additional braking AND additional cooling.

Re: Hydraulic fan controller DIY

Reply #22 –
IAT solenoid would be probably in the 20-30% fans speed speculating And 100% for retarder. Currently background speed is just tuning the fans like 1%. I'm curious how much airflow is being caused by drawing air thru caused by low pressure area behind coach. Any way to get any airflow thru is beneficial. I know of no way to tell? Maybe a manometer measuring pressure differential? I'm still not fully comfortable yet with the setup but hopeful it will work. I still won't fully know till it's hotter. Also having a manual control of the 100% retarder selection might be beneficial to help manually overcool prior to shutdown for the trip to drop radiator temps and engine compartment temps. Hadn't thought of that till this post. Brett your keeping me thinking. Thanks.
Scott

Re: Hydraulic fan controller DIY

Reply #23 –
It is very unlikely there will be a condition where the fans will not be spinning when you actually need the charge air cooler to cool incoming air.

Specifically: when the turbo is making boost and the charge air needs to be cooled, the engine will be under load. When the engine is under load, it makes heat.  When it makes heat, the coolant gets hot. When coolant gets hot, the "wax valve" senses it and runs the fans.

Re: Hydraulic fan controller DIY

Reply #24 –
Quote from: dsd –
. I'm curious how much airflow is being caused by drawing air thru caused by low pressure area behind coach. Any way to get any airflow thru is beneficial. I know of no way to tell? Maybe a manometer measuring pressure differential?

When you get that remote sensing photo tach, maybe set it up to read a fan like a pinwheel mounted right inside the engine compartment louvers on the rear.  That ought to give you some idea, and if you use a fan with known pitch should be able to calculate airflow volume.  Or, more simply, use a dc fan, let airflow motor it and measure voltage.

It's an interesting question with large implications regarding cooling efficiency.

Re: Hydraulic fan controller DIY

Reply #25 –
Quote from: krush –
It is very unlikely there will be a condition where the fans will not be spinning when you actually need the charge air cooler to cool incoming air.

Specifically: when the turbo is making boost and the charge air needs to be cooled, the engine will be under load. When the engine is under load, it makes heat.  When it makes heat, the coolant gets hot. When coolant gets hot, the "wax valve" senses it and runs the fans.

Notable exception will be on first starting out/before coolant up to temperature. Climbing a grade in the first 10-15 minutes could result in excessively high intake air temps.  I would feel more comfortable with a restrictor that gave LOW to HIGH not OFF to HIGH.

Re: Hydraulic fan controller DIY

Reply #26 –
I remember Monaco doing testing in AZ heat pulling a machine that simulated a constant load on the engine.  Once I road in a side radiator Diplomat they were testing and it had multiple hookup wires and notebook computers hooked up like a person in ICU.  The engineers were not happy with the results they were getting, and they were modifying various components on the exterior rear of the rv, and the programming of the ECU.  The engineers were from both Monaco and the engine manufacturer.

Re: Hydraulic fan controller DIY

Reply #27 –
Quote from: wolfe10 –
Notable exception will be on first starting out/before coolant up to temperature. Climbing a grade in the first 10-15 minutes could result in excessively high intake air temps.  I would feel more comfortable with a restrictor that gave LOW to HIGH not OFF to HIGH.
In thinking about this and what I've seen IAT must be maintained below 150 and colder is always denser. Having two flow control solenoids one for IAT at 30-50% and one for retarder at 100% with a manual control for pre shutdown cool down control Seems very desirable to me. I've drove our coach about 6k miles since we picked up at 100% fan speed the entire time. I really noticed the difference in the retarder temps and cool down time. Transmission temps also higher and was expected. Didn't give any thought about bedroom temperature till post drive and don't like at all. Manual Pre shutdown cool down will not effect engine temperature but will shed heat from radiator and engine compartment as it did in the past. Possibly trans temperature too? IAT can also be controlled by increasing baseline idle fan speed, but is a forever impact on fuel economy. Currently fans are turning ie not stalled but very low output. I felt that having them rotating even slowly was better than not. Very adjustable. If I get enough time I'll head down to Hoover dam today and watch how it performs pulling up the grade returning home.
Scott

Re: Hydraulic fan controller DIY

Reply #28 –
Quote from: wolfe10 –
Notable exception will be on first starting out/before coolant up to temperature. Climbing a grade in the first 10-15 minutes could result in excessively high intake air temps.  I would feel more comfortable with a restrictor that gave LOW to HIGH not OFF to HIGH.

In this particular case, the engine is controlled by an ECU that monitors intake temps.  If there is an issue with too high of intake temp, it will do something. What that something is, I don't know. But I have faith in the engineers at Cummins.

Historically, many diesel engines are turbocharged and do not have charge air coolers (CAC). CAC exist mainly for a power/efficiency reason on a diesel.  There is not a detonation risk, such as on gas engines.

Nobody knows the actually effectiveness of the CAC with the original setup vs the current setup. Perhaps there really isn't much change in inlet air temps (IAT).

Re: Hydraulic fan controller DIY

Reply #29 –
Those with Silverleaf or similar can report, but suspect in most cases that intake manifold temps with a properly clean CAC and properly running fans should be within 15-20 degrees of ambient temperature.

Here, lower/cooler is better.

Re: Hydraulic fan controller DIY

Reply #30 –
Last winter in the morning I left with a cold engine at the bottom of a long climb and part way up the climb a warning light came
on in the dash indicating high intake air temp. I eased of on the throttle and it went away. At the time I didn't know what it was
and now I believe that the rad fans were only running on the slow speed as the engine was still cold so the intake temp was too
high. I have now learned that the intake temperature can let me know that I am pushing the engine too hard an to ease off or shift
down. I have learned that I can use the intake temperature like an exhaust temperature sensor so not to push the engine to
hard. I have now got the intake temperature on my silver leaf and I just have to figger out the temp to back off.

Re: Hydraulic fan controller DIY

Reply #31 –
Quote from: oldguy –
Last winter in the morning I left with a cold engine at the bottom of a long climb and part way up the climb a warning light came
on in the dash indicating high intake air temp. I eased of on the throttle and it went away. At the time I didn't know what it was
and now I believe that the rad fans were only running on the slow speed as the engine was still cold so the intake temp was too
high. I have now learned that the intake temperature can let me know that I am pushing the engine too hard an to ease off or shift
down. I have learned that I can use the intake temperature like an exhaust temperature sensor so not to push the engine to
hard. I have now got the intake temperature on my silver leaf and I just have to figure out the temp to back off.
This is the reason for a IAT sensor and solenoid set to 30-50% background speed. If higher than normal IAT temps are reached the IAT solenoid is closed and ramps fan rpm up automatically 30-50% without you knowing. The Retarder solenoid would close off fluid flow causing fans to go to high 100% causing additional dynamic braking and max cooling during retarder use.  Extra cooling is always good, however it comes at a cost, fuel. But a nonissue if braking.
Scott

Re: Hydraulic fan controller DIY

Reply #32 –
Quote from: krush –
In this particular case, the engine is controlled by an ECU that monitors intake temps.  If there is an issue with too high of intake temp, it will do something. What that something is, I don't know. But I have faith in the engineers at Cummins.

Historically, many diesel engines are turbocharged and do not have charge air coolers (CAC). CAC exist mainly for a power/efficiency reason on a diesel.  There is not a detonation risk, such as on gas engines.

Nobody knows the actually effectiveness of the CAC with the original setup vs the current setup. Perhaps there really
Quote from: krush –
In this particular case, the engine is controlled by an ECU that monitors
Actually the ECM Controller has been deleted and a wax controller installed. So this is hopefully preventing repeat failure of the controller in the future and improving fuel economy compared to running failed at 100%
Scott

Re: Hydraulic fan controller DIY

Reply #33 –
First having the fan go to high speed while retarding makes sense. Second when I got my coach it already had a wax valve in it.
I gather from reading this post my coach didn't come this way.

Re: Hydraulic fan controller DIY

Reply #34 –
Quote from: oldguy –
Second when I got my coach it already had a wax valve in it.
I gather from reading this post my coach didn't come this way.

Your coach being a '99/ 320 came with a wax valve OEM. Seems like sometime in the 2000 year run is when they changed systems.

Mike

Re: Hydraulic fan controller DIY

Reply #35 –
Quote from: oldguy –
First having the fan go to high speed while retarding makes sense. Second when I got my coach it already had a wax valve in it.
So I am curious on what you baseline cold fan speed is set for?
If there is little air being pulled thru do to the low pressure behind the coach It would make sense to have a minimum airflow thru the system. Fuel cooler, CAC, radiator all need some loss of BTUs except if it's cold enough outside. I will never see me in those conditions again. Too cold. I would/will be on the near low side of fans speed if possible. Hasn't been warm enough last couple of days to see how it works. Been busy on other stuff too.
Scott

Re: Hydraulic fan controller DIY

Reply #36 –
Update to were am with this. I originally installed the wax valve in the lower hose past the transmission cooler. The engine temps are were I want them now, BUT the trans temp is running near 200 also. Retarder use is quite limited and takes forever to cool down. Really needs cooler source of coolant. Bedroom temperature stays saturated after shutdown. No good

Moved wax valve to upper hose. Back to being happier with retarder use and cool down better. Please understand I am comparing to A failed control system at 100% fans operation and it was much , much better with a max cooled radiator cooling transmission and bedroom was much cooler at 100% fan operation.

Next goal will be to add the Inlet air Temperature IAT control solenoid system
Maximum IAT with a below temp engine has been 139 at 70 OAT. When engine at operating temps it says below a 100.

Am planning to also add into the IAT solenoid And control.  A additional ON command for retarder use with delay off timer and brakes for added dynamic braking, will be at low power settings. No cost to operate fans at 100%
Because I liked the100% cooling prior I want to add in a manual ON to pre cool engine compartment and  Accessories  before shut down. Good for the engine and components and good for the bedroom to dump a bunch of saturated heat  before shut down. Especially in the summer.
 I'm sure the IAT doesn't need 100% but won't hurt other than fuel used and when at compleat operating temperature seems the fans are partially engaged and maintain below a 100 IAT  at 70 deg OAT.
Just need to locate part numbers and start acquiring them.
Scott

Re: Hydraulic fan controller DIY

Reply #37 –
So updating my progress. Finished my Foretravel distractions last week. Sent off to powder coat and is out of my hair. My employer has summoned my return to work May 1 this year instead of 2022. BUMMER. So I had purchase s solenoid shut off valve. The desirable adjustable valve is 250$ compared to my two position shut off valve. Open/closed at 100$. It is a normally relaxed open valve. If installing the adjustable I still would of needed the shut off valve. The adjustable is used to operate fans at 40-50% for IAT reduction. The shut off valve will use more fuel during IAT requirements but duration is short and infrequent for my driving manners. The shut off valve runs the fans at 100% percent like a failed electronic controller. All of my coach miles I've driven was with a failed controller. 7500 miles. I installed a single pull double throw switch for controlling the fans. I was able to hook up the override command fans to hi position. Easy to hear fans speed change seated in the drivers seat. Will be installing a Bosch relay to signal max fan speed during brake and retarder use. Will use that same circuit for the IAT commanded on also. Being able to max cool the drivetrain makes a noticeable difference when shutting down coach. Was a unrealized benefit that I really like. I'll post solenoid info once if got a few miles on it. More to come.
Scott

Re: Hydraulic fan controller DIY

Reply #38 –

So real close to completion. Ordered a radiator electric fan control unit Amazon.com: Hayden Automotive 3651 Adjustable Thermostatic Fan Control:...
And will used for the auto mode of the fan controller. Was able to hook up to the first half of the control switch. So in this position if any of the following are met it turns the fans on.
Hi inlet air temperature IAT
Application of the retarder,
Application of the brakes.
The fan controller wasn't made for this application but works well in testing. Adjusted ON temperature to 150 degrees and it shuts OFF at 115 degrees. Can adjust more if needed. Installed the probe in the inlet duct after the CAC. The controller also has a input for air conditioning and this worked perfect for triggering from brakes and retarder circuit. A additional benefit is when the controller has triggered the fan operation this backfeeds the over ride portion of the control switch at the drivers seat illuminating the fan on hi indicator in the switch faceplate itself.
Normal operation will be in position one Auto and when desired for cool down can be placed in override position two. Auto has a small led indication and override has a larger led indication. Anytime the fans have been commanded on by any manner the large led is illuminated on the switch. I'll make up a wiring schematic and get photos soon. Still need to make switch spacer plate also to finish.
Scott

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Re: Hydraulic fan controller DIY

Reply #39 –
So finally finished. Will take out for a test run in the morning. So really like having a indication of when the solenoid is engaged either manually or any of the other auto  modes.
Scott