270 jd excavator engine fan not speeding up

[jhexjd]

so on my 270 dlc john deere excavator ive got a problem with over heating part of the problem is that my engine fan(variable speed)will not speed up as it should i have checked out the fan drive motor the rpms are where they should be i did check the solenoid and it checked out fine too i believe it had 31 ohms which 20 to 30 ohms is good but i ruled it out because when auto idle kicks in and the engine revs down then the fan speeds up to maximum rpm if i go to unplug the solenoid at 1200 rpm it doesnt speed up the fan which means it is running full speed however if i unplug it at full throttle i find that the engine fan is only running at 1/2 to 3/4 rpms i believe that the fan should run full speed because the intake air temp sensor isnt getting a reading im just wondering if anybody could shed some light on this thanks

 

[biggerhammer]

I just replaced 0ne in a cat that was overheating. It had a code-just checked the wiring to the ecm then replace the fan. Problem was solved.

 

[heymccall]

An electronic viscous fan clutch never fully locks up...it will never, ever spin at the same rpm as the pulley when the engine is throttled up.

 

[mg2361]

Welcome to HEF jhexjd!

Serial number?

If you unplug any temp sensor or the fan proportional solenoid the fan should go to full speed. If it does not then there is an issue with the fan pump, fan motor or the spool in the fan control valve.

 

[jhexjd]

i dont have the serial number handy so the fan will not speed up unless u unplug the sensor or will it do the same thing if the sensor isnt reading

 

[jhexjd]

im nort sure if it would be worth it to check the wiring because the engine fan does rev up if the oil temps are at required temp when the engine revs down to 1200 rpm its almost like the intake air temp sensor not working is unnoticed by the ecm

 

[mg2361]

First lets confirm you are overheating. Did you check temperature with an infrared gun to confirm if it is overheating? Check top and bottom radiator temperatures to see if it is an air flow or coolant flow issue? Use a photo tach to check fan speed? Unplugging the fan proportional solenoid and running at wide open throttle with the hydraulic oil warmed up the fan should spin at 1600-1780 rpm. Saying the fan turns with temperature change means nothing without physical measurements.

 

[jhexjd]

i did check the temperature at the pump i guess ill have to check it at the rad i did check the fan speed and it is running at 1650 rpm but with the intake air temp sensor not working shouldnt it anyway be running full speed

 

[mg2361]

If that sensor is defective, yes it should be running full speed all the time.

 

[steve waldner]

Have had trouble with this in John Deere tractor witch has the same 9.0l motor , had to change the cylinder in the Sheeve that doesn’t have the spring , everything works but when it’s trying to run at full speed the cyl leaks internal not speeding fan to full speed . Causing all kind of problems . If not caught in time it will wear a grove into the pulley requiring u to replace it . When running full throttle with fan on high it should be louder than the moter . And blow u away .

 

[jhexjd]

my engine fan is running full speed it will literally blow u away but only when i unplug it when i reverse the fan with the soleniod plugged in it speeds up all yhe way then stops before reversing this i believe is normal but it proves to me that the soleniod is working (correct me if im wrong) im just wondering if the intake air temp sensor and engine fan problem could be connected could it be that my ecu is deffective

 

[mg2361]

Press and hold the upper right button on the monitor then turn the key on. After the bulb check scroll to service menu then enter. Scroll to troubleshooting and press enter. Then scroll to engine and press enter. What codes are displayed?

 

[jhexjd]

well the funny part is there r no codes at all

 

[mg2361]

We still need to confirm you are overheating and what is the source. Did you check the temp at the thermostat housing with an infrared gun when it is overheating? Check the top radiator tank/hose to the bottom tank/hose temps when overheating?

i believe that the fan should run full speed because the intake air temp sensor isnt getting a reading

How do you know your not getting a reading on this sensor? Are you looking in the monitor? Post a picture.

Post a serial number. There have been several product improvement programs for fan issues and I would like to check if they were done.

Also to check if the latest engine software is installed. They addressed some fan issues with software.

 

[jhexjd]

the serial number is ff270dx703490 i am checking in the moniter and the intake air temp sensor is blank however my hydraulic oil over heats before the coolant

 

[Mbar]

Have you pulled the proportional solenoid out and inspected it. Had a one do this and and lot of money was spent on it. Ended up finding a piece of trash lodged in the spool on the solenoid valve.

 

[jhexjd]

ill check that soleniod i did an oil sample and it came back saying that iron ppm levels are abnormal it said that the low ferrous density (pq) indicated that the wear was due to corrosion so im not sure what that means

 

[jhexjd]

We still need to confirm you are overheating and what is the source. Did you check the temp at the thermostat housing with an infrared gun when it is overheating? Check the top radiator tank/hose to the bottom tank/hose temps when overheating?



How do you know your not getting a reading on this sensor? Are you looking in the monitor? Post a picture.

Post a serial number. There have been several product improvement programs for fan issues and I would like to check if they were done.

Also to check if the latest engine software is installed. They addressed some fan issues with software.

im wondering if u did check and what u found

 

[mg2361]

however my hydraulic oil over heats before the coolant

If it overheats then it should of had codes. Again, I think an external temp test needs to be performed to confirm. Are warning lights/alarms on?

low ferrous density (pq) indicated that the wear was due to corrosion so im not sure what that means

The PQ Index is a relative measurement of the total Ferrous (Iron) metal content of your oil regardless of the size or shape of the debris.

I assume this was a hydraulic oil analysis, correct? What were those specific numbers? Just take note that if this was the first sample ever taken then the sample will have to be followed by more sampling to get a trend. Machines with higher hours that have not experienced oil changes for example may have high numbers, but not necessarily an issue. Generally speaking high "Iron" and high "PQ" translate to a component starting to fail, such as a pump, motor, cylinder, etc.

im wondering if u did check and what u found

Yes and no. There is a newer engine software available for your machine. However I could not get any product improvement history. For some reason it comes back with an error with the system when looking it up. I tried several times over several days but could not get the "PIP" information.

 

[jhexjd]

so my hydraulic oil temp according to the moniter will come up to 80 celsius at that point i usually stop to let it cool off but i know that it would keep rising im not sure at what point the alarm should come on but ive had it at 85 without the alarm coming on where should i do an external test on the side of the tank
so this is an hydraulic oil analysis and the iron ppm levels areat 37 and the low ferrous density (pq) index is at zero the oil i use is petro canada environ mv 46 i dont believe that the system has been flushed wiyhin the last 2000 hours which is how long ive had this machine this is the third sample ive taken and i noticed that it is actually getting better down from 85 ppm iron level but i guess my main concern is my engine fan not working properly
also is that a good hydraulic oil to use ideally i would use the hitachi stuff but the handiest would be esso if there is something in that line i could use