Cat 924G Engine Problem

[Hdbear67]

I have a Cat 924G that I got a call to look at because it will not start. When I arrive the operater stated that he had been running the loader all morning just fine. He then stopped to talk and the started up again and pulled forward and the machine just shut down. I checked both fuel water seperators and they were full of fuel. Checked to make sure I had fuel at all my injectors and I do. Check all fuses and they are all good. I then rechecked the fuel system to ensure I had no air in the fuel system. Has any one had any problem with this before? I am starting to believe that I may have a bad injection pump. I have been told that this has been a problem with these Perkins engines. I normally don't work on to much newer equipment. Any advice would be helpful

 

[Lee-online]

Does it smoke when cranking?

if not i would check the fuel shutoff solenoid on the pump. To shut down it is powered, by a timer. It could be powered all the time because of a bad timer or a wiring fault or more than likely, the solenoid is stuck.

 

[Squizzy246B]

Does it smoke when cranking?

if not i would check the fuel shutoff solenoid on the pump. To shut down it is powered, by a timer. It could be powered all the time because of a bad timer or a wiring fault or more than likely, the solenoid is stuck.

Yes, first place to start. A not uncommon problem. Also check voltage at the solenoid. Problems with these can be something as simple as a dirty terminal or earth.

 

[Hdbear67]

Very true. The machine does not smoke and I have not checked voltage to the solenoid yet. I have however disconnected the terminal and cleaned the contacts.

 

[cps]

Does it smoke when cranking?

if not i would check the fuel shutoff solenoid on the pump. To shut down it is powered, by a timer. It could be powered all the time because of a bad timer or a wiring fault or more than likely, the solenoid is stuck.

I second this, had this problem a few times!

 

[Dutch Cat-King]

No smoke means no fuel. Check the electrical system,does the stop solenoid works correctly.

 

[Hdbear67]

will do and advise when I get that far.. Thanks

 

[KTBAUGH]

We have a it28g that we use around our shop and a few weeks ago the same thing happened to us. We changed all the filters and finally figured out that there was something in the bottom of the tank that was blocking the fuel. When you would try to crank the machine it would suck the trash against the outlet inside the tank. We figured this out by blowing air back through the fuel line back to the tank and it fixed our problem. Give it a shot.

Thanks
kent
www.ktbaugh.com

 

[Hdbear67]

Have considered that as being the problem too, will check that and post results. Thanks

 

[Hdbear67]

Ok all here is the final out come. After check all above and getting fuel all the way to the injection pump but not to the injectors. I was fortunate enough to get a hold of the computer with the cat software to scan this machine..and based on the failures and and some input from a few other techs we came up with the engine protection module being the most likely cause.. Change this out and the Machine starts up and runs fine...

Bear

 

[mikef87]

Ok all here is the final out come. After check all above and getting fuel all the way to the injection pump but not to the injectors. I was fortunate enough to get a hold of the computer with the cat software to scan this machine..and based on the failures and and some input from a few other techs we came up with the engine protection module being the most likely cause.. Change this out and the Machine starts up and runs fine...

Bear

And yet another reason why computers do not belong in machines, they should have kept it simple and the machines would be fine.

 

[John C.]

Computers are in machines because you don't elect good politicians.

All that electronic control is mandated by the US Government and we elected them.

 

[ontarioparts]

I guess we are having a clash of the older generation of mechanics with the newer generation of mechanics.

I favour the ECM. It does it work at reducing emissions, saving fuel, and with one scan of the ECM the problem area can be diagnosed. Thats a fast way of getting right to the problem given the amount of sensors and controls the newer machines now have.

But, other than that, i hear ya. It can be a pain when one small sensor shuts the entire machine down. The older engines will operate in almost any condition.

regards
Caterpillar Alternator

 

[John C.]

To me the pain is the manufacturer designing a machine with electronics and setting up the diagnostics for a lap top computer, subscription software and special harnesses as the price of admission.

How many here have had a Cat loader go down for something easy and had no way to go but call out the dealer wrench at a thousand a day without the parts. How many fooled with a Cummins electronic motor in a Komatsu or Link-Belt and went through the same process. Maybe jump into an electronic power shift transmission with a harness problem spitting codes faster than a rattlesnake crossing hot pavement in the desert at noon.

Thirty years ago the service manual came with the machine when you bought it and the dealers aim was for you to wear it out without getting a call. Now days you are set up to fail through no fault of your own.

Lately I've been seeing the manufacturers incorporate the diagnostics in some machines. I would think a manufacturer would get a big jump on the rest by using something like the OBD system now used in cars. You still have to buy the reader but at least it works in all the makes.

As far as todays mechanics, most I've seen want to play with the electronics and not get their hands dirty. Let there be a double problem between something electronic and mechanical and they are lost. Have to pull an axle from a loader or split an excavator and they run away. Engines are never fixed in the field anymore. Pull it and bring it to the shop, that's too big for today's young guns to do in the field.

 

[mikef87]

My Cat 966G went down during a major snow storm because of some stupid sensor, my 1986 Trojan Loader with 12,000 hours fired right up on every cylinder, ran the entire snow storm and never had a problem. I would rather buy older equipment and spend the money to fix it up than to buy something brand new. I don't know if I want to buy anything newer than a C series on the Cat excavators because of the electronics. The electronics are going to kill this business if not the country.

To me the pain is the manufacturer designing a machine with electronics and setting up the diagnostics for a lap top computer, subscription software and special harnesses as the price of admission.

How many here have had a Cat loader go down for something easy and had no way to go but call out the dealer wrench at a thousand a day without the parts. How many fooled with a Cummins electronic motor in a Komatsu or Link-Belt and went through the same process. Maybe jump into an electronic power shift transmission with a harness problem spitting codes faster than a rattlesnake crossing hot pavement in the desert at noon.

Thirty years ago the service manual came with the machine when you bought it and the dealers aim was for you to wear it out without getting a call. Now days you are set up to fail through no fault of your own.

Lately I've been seeing the manufacturers incorporate the diagnostics in some machines. I would think a manufacturer would get a big jump on the rest by using something like the OBD system now used in cars. You still have to buy the reader but at least it works in all the makes.

As far as todays mechanics, most I've seen want to play with the electronics and not get their hands dirty. Let there be a double problem between something electronic and mechanical and they are lost. Have to pull an axle from a loader or split an excavator and they run away. Engines are never fixed in the field anymore. Pull it and bring it to the shop, that's too big for today's young guns to do in the field.

 

[tool_king]

John C
"You stated Engines are never fixed in the field anymore. Pull it and bring it to the shop, that's too big for today's young guns to do in the field. "That is not true .I work for the largest rental company in the USA as a road tech.I will fix anything that comes my way in the field with almost nothing to work with .I found that sometimes the older guys don't want to learn new things or new way of doing things. Please don't take this the wrong way. I have a guy at work that is like that .Some times you just want to bend a wrench around head. And some of the younger guys dont know how make things work with out nothing at all.

 

[mshack01]

Is anyone on line that has access to fault codes for a 924G. I have an active fault code of 081 123 105. The trans ECM was just replaced and flashed 2 days ago. Now I have this code.

 

[Lee-online]

Is anyone on line that has access to fault codes for a 924G. I have an active fault code of 081 123 105. The trans ECM was just replaced and flashed 2 days ago. Now I have this code.

MID 081 - CID 1231 - FMI 05

This diagnostic code is associated with the solenoid (brake charging). The FMI 05 means that the ECM has determined that the current of the solenoid is below normal.

The possible causes of this diagnostic code are listed below:


The energize circuit of the solenoid is open.

The return circuit of the solenoid is open.

The solenoid has failed.

The ECM has failed. This is unlikely.


Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear these diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 1231 FMI 05 is active before performing this procedure.


Test Step 1. CHECK THE SOLENOID.


Turn the disconnect switch and the key start switch to the ON position. Do not start the engine.

Disconnect the solenoid with the active diagnostic code from the machine harness.

At the machine harness connector for the solenoid, place a jumper wire from contact 1 (wire C881-BU) to contact 2 (wire T799-BR).

Observe the status of the CID 1231 FMI 05.
Expected Result:

The CID 1231 FMI 05 remains active. The FMI has not changed and the "05" is still active.

Results:


YES - The diagnostic code remains active. The jumper wire does not affect the diagnostic code. Proceed to Test Step 2.

NO - The diagnostic is no longer active. The solenoid has failed.
Repair: The solenoid has failed. Repeat this Test Step "CHECK THE SOLENOID" in order to verify the solenoid failure. Replace the solenoid. Verify that the new solenoid corrects the problem.

 

[Diagonal Brace]

Lee you are one of the most valuable assets of this forum. We thank you.

 

[Dutch Cat-King]

Have you replaced the pump (fan/brake), a new version is without a solenoid.
If you talked about this pump and serialnumber is in the range under, flash the ECM
If you talk about a machine with serialnumber DDA, RBB , WMB or RTA , WGX DZF you will install a new flasfile and configure the solenoid (brake/fan) as NOT INSTALLED.