I've got a Cat 239D with just over 900 hrs on it , recently it's been running warmer than normal in the 203 - 208 degree range. It has the variable speed hydraulic fan that doesn't seem to be spinning fast enough to move enough air through the radiator. I've pressure washed the radiator multiple times to be sure it's clear now if I unplug the solenoid on the fan motor it will spool up and cool just fine any suggestions on how to test the solenoid or just replace it ? Also have been told that the hydraulic fan motor may need to be calibrated, any feedback on that ? Thanks, jr
There's a fan speed spec for those hydraulic fans. I've had to calibrate a couple of them. You need a digital tachometer to read the fan speed. If its out of spec then you'll need CAT ET to run the fan speed calibration.
You may want to pull that solenoid valve and make sure it isn't stuck partially open. Had that on a 299d
I actually just went thru this mess with my 259D. I had washed the radiator several times, CAT washed and blew it out, still got hot. I finally got a 90degree fitting for the end of my pressure washer, dropped the fan and washed up thru the radiator. You would not have believed all the crap that came out. I questioned CAT several times about the fan not spooling up. Apparently on these it isn't so much variable speed as it is a two speed. They said the only time it will speed up is when it is doing a regen. Even when my hi temp warning light came on it did not spool up. But, like you said, unplug the solenoid it goes full speed. I did have mine calibrated, nothing changed. This is the picture I took after i finally got the 90 degree fitting and started washing. About two hours later it was much better.
Do you need the seal kit to check the valve? Didnt want to pull it off and look with out the seal kit if so.
Not to check it. Only replace the orings if flat or damaged.
I have a new solenoid valve coming just in case , will check old one when it gets here. I ran it today with the solenoid unplugged and the temp stayed around 185 but once in awhile would bump up to 190 or so with the ambient temp around 75 degrees that still bothers me a little. Installed new thermostat last Sunday with no difference in temps . Temps verified with an infrared temp gun. Cat dealer tech line suggested water pump impeller may be eroded ??? I'm sure the radiator is clear I've had my diagnostic camera in there and can see right through . Thanks for the input !! jr
I wouldn’t worry about temps around 190, the engine temp will change just a bit depending on the load conditions. Your issue is the amount of air going through the radiator.
Interesting that you'd mention the digital tachometer , I had the radiator raised on my 226B3 today and saw the reflective tape on one of the fan blades. Might just get my tach out and see if it still works .
That's what I'm afraid of , when I put my mower on when it's 95 degrees out and run it in High Flow . 90 minutes one way to my Cat dealer may have to make the trip.
That's what I didn't understand if the solenoid valve actually varied the oil flow or just dumped oil to the return. I've had my camera up in there and can't see any debris in the cores.
Is this solenoid valve just either open or closed ? Or does it actually vary the flow ?
A Serial Number would help to get exact information. Electrical Schematics differ between various Serial Number prefixes. From what I can see the 396-4882 solenoid is referred to as the "fan demand". It is driven by a PWM driver from the machine ECM, therefore the most likely scenario is that it is completely variable between 0 and 100% and will depend on coolant temparature. Otherwise I don't see a reason for it to be driven by a PWM driver. Edit: I was right. Taken from the machine Service Manual - "Hydraulic Demand Fan Control The control system will monitor engine coolant temperature, hydraulic oil temperature, intake manifold temperature, and ambient temperature to control and limit the fan speed. The monitoring is done by proportionally modulating the hydraulic oil pressure to the hydraulic fan bypass valve. This feature is also known as the engine cooling fan. This system will also run at maximum speed during a Diesel Particulate filter (DPF) regeneration cycle. This system will limit minimum fan speed to 1200 RPM anytime the Air Conditioning switch is ON." To test the fan speed appears to require Cat ET and a phototach - see attached.
Serial# BL901413
Thanks for the information. I can confirm that the info I posted above is correct for your machine, the fan speed control solenoid is variable type and driven by a PWM signal from the machine ECM. If you want a copy of the Electrical Schematic click on my username and start a Conversation. Send me your email address and you're welcome to it.
So that then tells me that the ECM varies the voltage to the solenoid to control the flow of oil past the valve then. IE: varies the length of the plunger or orfice . After reading your response again, there are more variables at work here too, there must be intake manifold and ambient temperature sensors also. Thanks Nige !!
So the saga continues , picking up the 239D Monday from the cat dealer . $1500 worth of diagnostic time later nothing wrong with it and with 900 hrs. on it I shouldn't expect it to run as cool as it did when it was new. They did calibrate the fan , so I'm going to run it and when it chucks a rod they can warranty the engine.
Did you ask them to explain the thought process that they used to come to that conclusion..? I would have, just for sh1ts & giggles. It ought to have induced a bit of squirming.......
Oh, tomorrow when I pick it up there will be a soul search on their part.
I am having a hard time wrapping my head around the fact that the service writer basically told me that Caterpillar was manufacturing an inferior product that wasn't designed to have a useful life past 900 hours .
Well just remind the dealer of this - it is typical in a fleet application to trend certain parameters over extended periods, sometimes measured in years, in order to get advance warning that something is going pear-shaped, or at least to start looking for reasons why. Coolant temp is one of them. I realise that your machine doesn't have the complex on-board electronics to do what we do, but the principle is the same. If we don't expect a $2m haul truck coolant temp to significantly change over time without going looking for a reason, why should you expect any different with your machine..? What they said ain't logical, and nobody in their right mind can argue that it is.
Nige I'm 63 yrs old and have worked around and on diesel engines all my life and have almost a totally Cat fleet . I have never had an issue like this that couldn't be solved, but they way the service writer acts it's as if if his computer doesn't have an answer then there is nothing wrong. I do know 2 things, I will find an answer to this issue with or without the dealers help and tomorrows meeting may or may not cost his employer a $100K plus sale and many more.
Nige I don't know you or know where you are or what you do but I will tell you this I truly appreciate your knowledge , input and expertise that you hand out freely my friend .
Have the conversation with the Sales Manager before you go to speak to the Service Dept..? That way it gives him chance to call them and let them know which way is up before you arrive. Either way let us know how it turns out.
Age-wise I got you beat by almost 5 years. Having spent many years working for dealers back in the days when the Cat brand REALLY meant something, experiences like yours with wet behind the ears whippersnappers boils my **** quite frankly. Most of what I know falls into what I consider to be the "I thought everyone knew that" category...... It still never fails to amaze me that "they" don't, even after all these years.
Nige the first call I make tomorrow will be to my salesman who will talk to the sales manager whom I know fairly well , next call will be to my product support guy who is a personal friend. Then I will make an appearance at the service desk and see if the service writers answer and attitude have changed. If needed I have a close personal friend that is friends with the owners. Now on another note for this machine serial # BL901413 would you know if there is an update either hardware or software for the advanced display that has the date and time like the current models do ?
While I was poking around looking for updates I came across this ......... I wonder if it has been installed your machine..? It only came in from the factory at BL91560-Up, so your machine was not originally built with it. I will continue looking for any other info. Another thought. Drop a PM to Mark250 of this parish in case he hasn't spotted this thread. He's pretty much a whizz on the SSL/MTL/CTL Product Line.
Check out this list of software updates. There may be something in there. I highlighted one regarding a real-time clock.
Thanks Nige for the info , I'll let you know how today goes .
What the **&&^%! Are they trying to tell you this is a machine built for homeowner use only? 900 hours would only be six months use at 40 hours a week. Guess you need to go buy a good used Case 1845C, when I retired back in 2015 the quarry was still abusing the crap out of one they bought in 1989! Tell the salesman that will be your next purchase if they don't eat the BS of the no answer "$1500 worth of diagnostic time" and figure out the problem!
Ask them to run through the fan calibration procedure while you are there. It only takes a couple of minutes to do it. Min fan speed should be 1000rpm and max fan speed should be 2900rpm, +-50 rpm. The machine has no idea how fast the fan is actually spinning, so you could have them set the max fan speed a little higher than spec to get more airflow. Keep in mind that the fan motor is driven by the charge pump, which is driven at engine speed. If the engine lugs, the charge pump slows down and flow decreases. Less flow out of the charge pump means less flow to the fan motor which causes slower fan speeds. If you are running a brush cutter and the engine is constantly staying lugged back to 2500rpm, then your max fan speed will also be slower. If you unplug the two wire connector going to the fan solenoid, the fan should go to full speed. Maybe try running it like that for a bit and see if that helps with the temperature issue. It will trigger a diagnostic, but that will go away when you plug the fan back in.
Very good idea. If you know what the resistance of the solenoid coil is, find a resistor of the same value and install it on a 2-pin connector, then when you disconnect the solenoid plug the resistor in where the fan control solenoid coil normally connects. That way you would get full fan speed without a Diagnostic Code.
It would be pretty easy to measure the resistance with a multimeter. If you didn't feel like doing that then I would start with something around 5.3 ohms
I picked machine up yesterday from dealer , they did do the fan calibration on it they also installed some new software . I will have the mower on it later this week and it will be close to 90 here so we'll see what happens. I have already run the machine with electric unplugged and it did help. Still seems odd to me that it went from 185 - 195 all day long to 205 - 208 basically overnight. The dealer did tell me I was doing a good job in keeping the radiator clear .