CAT 930G Cooling Issues

[cc431]

Hey all!
I run a CAT 930G wheel loader. It’s a multi-use machine used at the concrete production facility. Most times it’s used for loading the concrete plant with aggregate/ loading end dumps etc.

We acquired the machine second hand with 10k hours on it now. It is having cooling issues with its hydraulic fan. The fan doesn’t seem to be matching the cooling demands on hot days.

The only issue seems to be the hydraulic oil cooling. Engine and transmission temp stays in a normal range. All the radiators are clean and blown out, coolant is kept up and doesn’t leak. The hydraulic oil temp gets 1/2 notch from redline on hot days (too hot for my liking). The cooling fan spins a constant speed and never increases.

On the dash, upon starting the machine the flashing exclamation mark flashes and battery light on. It came to us like that when we bought it. No battery issues however are present to us over the year we have had it.

Periodically (once in a blue moon) the machine with have a glitch when restarting the machine after shutting it down quickly. The engine rpm will be shown as 0, however the machine runs perfectly fine. When this happens the cooling fan somehow works perfectly. The fan rpm increases when you rev the engine and audibly you can tell it’s pulling much more air through the machine. The hydraulic oil stays at a normal operating temp when this happens, much cooler anyways. Also the brakes have no issues either. You can stomp on the pedal and no alarm. More on this in a minute…

If you restart it after a glitch it returns to spin constant and the brakes also have low pressure. Every time you slam the pedal idling (for testing purposes), slowing down moderately, or coming to a stop the alarm sounds and light illuminates. When the hydraulic oil is extremely hot the pump seems to get a jittery flow as well when doing short up and down loading cycles.

Also to add, the engine likes to bog down (under 800rpm) when dump and raise the bucket and certain curl and raise motions. Must be a hydraulic valve restriction or something. I tried looking on the forum for a similar issue but couldn’t find exactly something like this.

Anyone have any ideas on what I should check or look for? Also this is my first post on the forum, so I’m glad to be here!

 

[Nige]

Missing the Serial Number……..

Also do you know how to get into the diagnostics menu.?

 

[truckdoctor]

You might have one issue or two issues. The fan and the brakes should run off the same pump which should be on the engine. I would have to look it up but there should be a solenoid valve that runs the fan circuit. That solenoid valve on the larger loaders is under the right step. If you unplug that solenoid the fan should go to full rpm because it's asking the fan pump for full oil flow. This is probably why when the glitch happens you don't have heating problems. The alarm and light are probably for a low brake pressure code. Look for a switch with a check mark on it. If you hold the switch down it will display numbers normally where the hours would be on the quad gage. It should be 3 numbers followed by 2 numbers. It would look like 347 and then 01. Write those numbers down because they are the fault codes. This will narrow up what is causing the issue. It sounds like the fan/brake pump is working but it's not getting the right info to operate. Plus your brake accumulator might be low as well which is the helping the situation.

 

[cc431]

Serial number is CAT0930GTTWR02022. no I don’t know how to get to that menu

Missing the Serial Number……..

Also do you know how to get into the diagnostics menu.?

 

[cc431]

You might have one issue or two issues. The fan and the brakes should run off the same pump which should be on the engine. I would have to look it up but there should be a solenoid valve that runs the fan circuit. That solenoid valve on the larger loaders is under the right step. If you unplug that solenoid the fan should go to full rpm because it's asking the fan pump for full oil flow. This is probably why when the glitch happens you don't have heating problems. The alarm and light are probably for a low brake pressure code. Look for a switch with a check mark on it. If you hold the switch down it will display numbers normally where the hours would be on the quad gage. It should be 3 numbers followed by 2 numbers. It would look like 347 and then 01. Write those numbers down because they are the fault codes. This will narrow up what is causing the issue. It sounds like the fan/brake pump is working but it's not getting the right info to operate. Plus your brake accumulator might be low as well which is the helping the situation.

Ok on Monday I will try this out!

 

[Nige]

Serial number is CAT0930GTTWR02022. no I don’t know how to get to that menu

Thanks for posting the Serial Number. See the attached procedure to access Diagnostic Codes from the instrument panel.

Go through the list of Codes paying special attantion to anything with the letter "A" in front of it which means it is an Active Code. HOWEVER don't ignore the non-Active Codes, make sure you post a list of them as well because they may provide other important clues.

 

[cc431]

Thanks for posting the Serial Number. See the attached procedure to access Diagnostic Codes from the instrument panel.

Go through the list of Codes paying special attantion to anything with the letter "A" in front of it which means it is an Active Code. HOWEVER don't ignore the non-Active Codes, make sure you post a list of them as well because they may provide other important clues.

Wow this is great. Thanks I’ll get back to you on Monday when I’m back at work

 

[cc431]

Here are the codes there are just a few haha… (none were active) or showed A in front)


Left Right
081 0247 09
081 1251 00
081 0811 09
081 0168 04
036 0247 09
036 0320 02
036 0174 02
036 0342 02
036 0105 03
036 0102 03
036 1684 14
036 1684 10
036 1684 07

 

[Nige]

Thanks for that, but you missed the most important bit - which ones out of that long list had a letter “A” to the left side, indicating that they are Active.?

Hopefully that will help narrow the field down somewhat.

 

[cc431]

Thanks for that, but you missed the most important bit - which ones out of that long list had a letter “A” to the left side, indicating that they are Active.?

Hopefully that will help narrow the field down somewhat.

Oh sorry. I edited the post up top right after I posted it to say none were active. Didn’t see any A codes

 

[Nige]

Oh sorry. I edited the post up top right after I posted it to say none were active. Didn’t see any A codes

Well that at least appears to confirm that the source of the problem is not a fault in the electronic control system. Even in the above list of inactive Codes there is nothing relating to the fan/brake system.

According to what I can see your machine has a standard (not a reversing type) fan motor. It should look like the illustration below. The next thing I would suggest is to check that the fan motor speed actually varies. You will probably have to remove the radiator grille (20 bolts) to gain access. With the engine idling unplug the connector to the fan motor control solenoid #5. Does the fan speed increase or stay the same.?