Cat 308e2 — Excavators

Simon C said: If the battery drops to 8 volts when starting, you are drawing too many amps from starter, battery is defective, or you have hydraulic load causing extra amps draw. Click to expand... This got me thinking. A hydraulic pump swash plate stuck at full displacement would cause these symptoms too.

Unplugged crankshaft sensor. Motor ran even worse. Also took longer to fire a cylinder, plugged crank back in. Same spitting and spudering like the beginning. I Unplugged the cam shaft sensor. Tried to start it and it has the same spitting and spudering like nothing has changed

Would a Cat ET read all these issue. Which version is needed.

Chrisso said: This got me thinking. A hydraulic pump swash plate stuck at full displacement would cause these symptoms too. Click to expand... Had that on a Ingersoll Rand large compactor. Engine would not start, got to job with batteries disconnected and told change the starter. I did and no start but would turn over. After trying that a couple times had someone else crank it over and crank went forward 4 turns. Then it turned counterclockwise about 3 turns. End of job. Hydrualic filter was totally full of cuttings. 6000 hrs machine junk. So it could be a hydraulic problem, has to be ruled out. Simon C

Stevepala said: Would a Cat ET read all these issue. Which version is needed. Click to expand... Your machine was built in August 2016, so theoretically any version of ET from 2016 onwards should connect. I suspect that even ET from a couple of years earlier than the machine, say 2014/2015, would also work. If ET is hooked up to the machine then please ensure that a Product Status Report is downloaded before any parameter is modified or Diagnostic Code is erased. There are plenty of videos on YouTube showing how to do it. Just make sure the PSR is downloaded in the optional Adobe pdf format.

Chrisso said: This got me thinking. A hydraulic pump swash plate stuck at full displacement would cause these symptoms too. Click to expand... So what happened was the machine started an ran fine, idled up with was working. After 5 minutes it started to loose power slowly. Like a clogged fuel filter. So changed all filters and here we. So I don't think its a hydraulic issue

Have you checked the tank for contamination.? There should be a drain valve or plug underneath it somewhere. If the primary filter/water separator has a clear bowl does it fill up with fuel before you run the engine.? The symptoms you describe above are somewhat typical of a blocked fuel system.

It has a brand new cartridge filter and online filter along with a new fuel pump. I blow out the lines with air compressor to check for a clog. After all the filters and pump change all air was purged and fuel flow as it should

Stevepala said: It has a brand new cartridge filter and online filter along with a new fuel pump. I blow out the lines with air compressor to check for a clog. After all the filters and pump change all air was purged and fuel flow as it should Click to expand... Was any of the purging done while the engine was running.? It wouldn't be the first time that a floater in the tank got pulled into the end of the suction line when the engine was pulling fuel, then when the engine is stopped it drops away and gives the impression that there is no problem. Just saying you might be missing a trick not looking closer at the tank, even if only to rule it out.

Nige said: Was any of the purging done while the engine was running.? It wouldn't be the first time that a floater in the tank got pulled into the end of the suction line when the engine was pulling fuel, then when the engine is stopped it drops away and gives the impression that there is no problem. Just saying you might be missing a trick not looking closer at the tank, even if only to rule it out. Click to expand... Not sure how hard it would be to run it off of a Jerry Can of fuel with return fuel into a different can so there can be no chance of bubbles getting into the line. As Nige said above, need to rule out a floater that just goes when suction is on tank. Had a Volvo Rock truck would not take fuel even with 5 psi air pushing into tank. Disconnected the suction line from filter and blew hard with air and suddenly bubbling in tank. It immediately took fuel and started after that, never fixed it as taking tank out was a pain. Owner did not want to fix. Local county had a garbage compactor that died with no fuel, Changed all the filters and ran again for 30 seconds and died,. They worked on it for full day with Cat support, only to find out the second set of filters were plugged instantly. New filters again and never died again. Cost day and half of Finning Labour to find out. Might not be your problem, but might be, needs to be ruled out. Simon C

Nige said: Was any of the purging done while the engine was running.? It wouldn't be the first time that a floater in the tank got pulled into the end of the suction line when the engine was pulling fuel, then when the engine is stopped it drops away and gives the impression that there is no problem. Just saying you might be missing a trick not looking closer at the tank, even if only to rule it out. Click to expand... No, the engine lost power and all the filter changing was done after. But im going to purge everything again.

So while my guy Kyle been chasing electrical stuff I decided to chase fuel flow. With the key in run position. At the inlet to the injector pump was a very strong flow. I put it back on and removed the return line from the injector pump, very little flow like the size of a pencil lead. So I put the return line back on and cracked an injector line at the head. No flow at all. I thought this was odd since someone previously asked me to do this or am I doing a purge at the injectors wrong. FYI I had a cat 235C and changed injectors before then purged them by cracking the line and hand pumping it. Steve

Well there's your low rail pressure. Cracking lines while engine is turning is not a recommended practice and actually does more harm then good to your fuel lines, not to mention the safety aspect. (edit: This applies to all common rail engines.) Your 235C was a mechanical fuel pump and is a different kettle of fish compared to your 308 with a common rail fuel system running at tens of thousands of PSI. There's some more checks you can do in post #29 of this thread... https://www.heavyequipmentforums.com/threads/caterpillar-308-stalls.107311/page-2#post-1208177 Whatever you do, don't pull the fuel pump without timing the engine. There's a special procedure for it. But first things first, I'd want to know what the engine ECM 'thinks' the rail pressure is before tearing into it.

Today I hooked up the Cat ET. The requested fuel rails pressure and actual pressure was within 20

I the looked at the exhaust regen. This was at the max number and a regen was requested. Could thus be the issue. The soot level to high? Could it plug yhe exhaust

I also had the 2 codes for fuel rail and engine speed sensor

What should I do next?

My guess is to check the wiring, and sensors for if you see anything out of the ordinary. Can you pull the speed sensor out and check the end for dirt or damage. I don't have the schematics or for your unit, but am sure someone will have. Simon C

Stevepala said: What should I do next? Click to expand... Here's what I suggest, in the following order. One thing to note is that the Diagnostic Codes on your screen shot were Logged, meaning that they were Active at one time but are not Active at the time the ET was connected to the machine.

1. Download a Product Status Report using ET. See this LINK to a training video that walks you through the process. Take note of the video at around 6:00 where it shows how to download the report in an optional Adobe pdf format. You will nee to do this because otherwise if you upload it here no-one else will be able to read it.
2. Use ET to erase the 4 Logged Diagnostic Codes shown on the screen shot. When you have done this, disconnect ET electronically using the menu bar then turn the key OFF for 30 seconds. After that, power the machine up and connect ET again. Check that all the Logged Codes have been successfully erased. If that is the case download a second PSR as confirmation of that.
3. Attempt to start the engine a dozen or so times. Reconnect ET and check for Active or Logged Codes. Report your results.

Hello, Let me start this post with a thanks for the help so far. At this point I'm even more puzzled after the ET scans. I was hoping for a clearer picture of the issue and now it's just not. So I followed Nige's request and here is the first PSR.