Hi all. I’ve seen other posts regarding the pressure sensor switch. The skid stopped all of a sudden and is like the stop solenoid isn’t working. Engineer said it’s fuel pump as nothing is coming through up to injectors. 1) is there a solenoid I can buy to try before the costly part being new fuel pump 2) if it’s whole pump. Is there anywhere cheaper than CAT? (Based in Uk) Thanks
Update. I have 2 volt going to plug (presumably the cut off solenoid) Is this correct voltage?
There is no "cut off solenoid". It uses a SCV (Suction Control Valve) that receives modulated voltage. A failed SCV should have a fault code stored. Is the lift pump working?
Serial numbers always help with troubleshooting a problem. Does it have a common rail fuel system? If so do not mess with the fuel lines going to the injectors. It should have an electric fuel transfer pump in the engine compartment. Open the back door, look on the left side below the fuel filter. Just turn the key on and go back to the pump and see if it’s on, you‘ll be able to hear it. If not, unplug it and check for voltage. If no voltage, check the fuse.
No fault code stored. It’s a 299d2xhp DX204524 Lift pump fine. Fuel goes to fuel pump but doesn’t go through. Cat engineer took pipe from fuel pump off and nothing came through.
Does the cat engineer have ET?
The machine is equipped with an Advanced Display screen where Active & Logged Diagnostic Codes can be seen. ET would be a bonus but not absolutely essential.
yes and no codes. I had an error message come up when it happened which was fuel leak severe.
I’ve seen this happen before when those pumps suck even the slightest amount of air. Top off your fuel run that transfer pump a couple 5 minute cycles and try again.
ET for status
The fuel pressure is good from tank, both filters and to the fuel pump
I’m pretty sure there is a troubleshooting procedure for the fuel leakage severe fault. That would be a good place to start.
Where would I find the procedure? The error / fault only flashed briefly when it happened
OK, so based on previous experience there are various posibilities. The first thing I would suggest is have your guy take a look inside the fuel suction valve of the HP fuel pump and check the condition of the spring. See this thread. Report your findings. Once the posssibility of a broken spring is eliminated other possibilites can be considered. HeavyEquipmentForums What mechanical maintenance (if any) have you done on the fuel system recently.?
We'll come to that once the possibility of a broken spring has been eliminated.
Here's another question for you. You said it "stopped all of a sudden" but when the engine died did it splutter to a stop or did it die as though someone had turned the key off.?
It died as if someone turned the key off
I'm with Nige on this one If it is the broken spring, you cannot buy spring only. Best bet is to try to locate a core,(junk) pump and salvage the spring.
TBH I reckon a valve spring of suitable dimensions would serve as a perfectly acceptable replacement. I’m still waiting for someone to come up with a few measurements….
This one. . . . maybe? Plunger return spring for some Denso HP5 pumps - Diesel Injection Pumps Plunger spring for some Denso HP5 pumps injectionpumps.co.uk
As we would say, that llooks awfully adjacent..... And the best part for the OP is that the seller is in the UK.
A quick update. Machine is in main dealer. They’ve put new pump on, looking at putting on fuel lines, injectors and the fuel relief valve as they aren’t getting correct pressure and have found contaminated fuel with metal. I have asked if they put the engine onto correct timing and I was told this isn’t crucial as it’s a common rail engine. I feel they simply took old pump off and put new one on without double checking timing.
Do you fancy asking them why they did not follow the Cat service manual procedure and time the engine before removing the pump.? Just because it's a common rail engine doesn't mean there isn't a procedure to follow to R&I the HP fuel pump. See Step 1. IIRC the pump has to be "timed" with respect to the crankshaft in order to correctly position the rotating parts of the pump and balance the force necessary to rotate it against the pressure pulses of the injectors opening/closing with the mechanical balance of the rest of the engine rotating parts such as crankshaft, pistons/rods, etc ,etc.
This is the last report. They simply said the engine was already timed correctly. I’m guessing they took pump off by seeing it was in the markings without checking which cylinder was TDC.
That's a bit different to saying "this isn’t crucial as it’s a common rail engine". The service report mentions nothing about timng the engine before removing the pump. Simply says "original HP pump stripped, found damage to various components, etc, etc......" If they did not time the engine and pump during disassembly there is still the opportunity to do it when everything is reassembled. AFAIK a new pump is supplied with the shaft locked in the correct position to be installed straight on to an engine that is already timed.
They told me they took old pump off and put new pump on and tried it with no success. Also said where’s the key but there wasn’t one when I took inspection plate off. There wasn’t even a notch on the cog for one to go into.
I would go back to them and ask why they are not following their OEM's published procedure to R&I the pump.? I'm not saying it will make the difference between the engine starting or not, but if there is a procedure they should be sticking to it. Tell them this, and make it appear that you are a Jedi master - Despite supplying a "constant" flow of fuel, the HP pump is still a piston pump which delivers fuel in pulses. The pump must be timed so the pulses coincide with the injection events as triggered by the engine ECM. Because said injection events are tied to the position of the rotating parts of the engine therefore the HP fuel pump has to be timed to the engine. QED.
These engines will absolutely not run if timed incorrectly. Not only are delivery pulses matched to need as Nige points out. the HP5 pump on tier 4 final V3800/ C3.8 does not have a typical Scv, it pulses the output solenoid on the top of the pump to control flow and pressure. The only way the ecm knows when to pulse is from pump timing, there is no sensor on the pump itself. One tooth off time and it will start and die. One off the other way and no start at all. If you/ they did not mark the pump gear at disassembly they will have to remove from the cover and retime from scratch.
Thanks for confirming that. I was beginning to doubt myself.
Sounds like they just caused another few hundred in gaskets and another grand in labor. Have to drain coolant and take pump off and everything, to get the front cover off. Now it’s sounding like an extra couple of grand.
Any update on this one.? Enquiring minds would like to know.
Hi Nige, They ended up putting new fuel pump, fuel rail, injectors, pipe etc to no avail. Then went back to “check” timing via taking rocket cover off iirc. Anyway the report said it starts and runs but there was a plastic Y junction water pipe that started leaking when put back together so now waiting for that to come in. Was supposed to be in 10 days ago but now it’s on the 21st this month apparently. Got a new 275xe and gb124 on order which is coming in first week of June so not happy been down a machine loosing work and income.
Well surprise surprise............ Bullshitters of the highest order IMHO, which as an ex-employee of the company pains me to say.
What’s my options as they never timed it correctly from the beginning. I’ve a new one coming but if this is the way they they will treat me going forward I’m not sure about keeping it
They would have to pull off the front cover to ensure that the engine was timed correctly before installing the pump. That should be at their expense not yours, seeing as it would not have been necessary if they followed service manual procedures. I dunno about others but IMO you have good grounds to challenge the invoice. Who knows how many parts they installed that were unnecessary in their attempts to get the engine to run.?
That’s why I hate anyone else working on my stuff. They usually throw the damn parts cannon at it, knowing that they won’t have to pay for it. Not to mention that they mark the part up 25%, that really chaps my ass.
Why's it so hard to have integrity these days?
Especially when it's a dealer for the OEM. I know everyone makes mistakes, and in this particular case it ought not to be too difficult to hold their hands up and admoit that they got it wrong.
We had a job go wrong recently and the first thing we did was tell the customer what happened and that they will not be billed for the mistake. It sucks to lose money but I think you have a much better chance at retaining a customer when you're straight up and fair with them. It shows you run the business with integrity and that you stand behind your work.
On another note… As I am up and running again. I am having issue with Aux 7 (pin A)? I have 2 speed tracking working but clicking the trigger to activate auto on and off doesn’t seem to work. I have used volt meter at the socket and it doesn’t seem to be getting power when pressing the trigger. Any ideas? BTW I’ve had the grader rigged up with a rocket switch before and have just put the wires in to the pin a.
Not sure I'm following you. Two speed can't work unless you trigger it on and off with the LH joystick trigger. Does the problem occur only with the GB124 coupled up? Does everything on the GB124 work?
Sorry, I mean 2 speed tracking works with trigger but switch it to Aux 7 and I don’t get anything to the 14pin socket
Do you have a wiring schematic for this machine by any chance? The A pin on the 14-pin plug is controlled by a relay. There's two banks of relays behind the seat to your right. An upper bank and a lower bank. Go to the upper bank and pluck out the lowest relay, swap it with another and test. Failing that you'll need to start tracing wires from the AUX7/2-speed switch to that relay, where a schematic will be most helpful.
If he doesn't have one I can send him a copy.