CAT 279D nightmare, cam/crank waveform wanted

I'm trying to sort out a shop nightmare... Rented out a CAT 279D (GTL). Reportedly it "melted" two hydraulic hoses out in the field. Talked to the tech that worked on it, and he told me the hydraulics go so hot that the hoses melted out of the crimped fittings (Kurt compression style). Fast-forward a week later and the machine gets back to the yard. Couple of the guys ask me to take a look because it's making a strange noise. Sounded like a bottom end noise in the engine but wasn't entirely sure. Told them to pull the rocker cover and look for any loose rockers, and if not yank the engine and flip it upside down and pull the sump. Turned out #3 spun a rod bearing. All the other rod and main babbitt looked fine. Not sure what caused the spun rod bearing, but it beat the hell out of the crank and the cylinder bore. Shop sourced a reman Kubota V3307 long block to replace the original ~3300 hour engine instead of rebuilding. Injector's got sent out to get tested, came back as perfect condition. Shop's senior tech and his apprentice did the engine swap, and it wouldn't crank afterward. Another tech got involved, and they determined the starter was faulty. After the starter was replaced, and it still wouldn't crank the three of them started randomly moving wires around. The main ground terminal eye that was supposed to bolt to the engine block was on the starter B+ solenoid terminal. They moved the ground terminal to the field side of the starter solenoid. The engine would crank momentarily, and then stop, repeat. Super asked me to take a look at it, after putting the ground back on the engine block, it wouldn't crank it all. I poked around and determined that even though the ECM was communicating, it had an internal fault. The shop sourced a used ECM out of a CAT 279D from eBay. Turns out it takes a special program to flash these ECM's, and not just ET WinFlash. I replaced the ECM and encoded the injector trim without flashing. Got the engine cranking over like it should, but it still wouldn't start... Started chasing fuel, lift pump -> high pressure fuel pump had a lot of flow and no air. Rail pressure was reading 0 psi. Pulled the fitting from the HPFP -> common rail and there was nothing. Disconnected the SCV connector and cranked over, now there is fuel coming from the HPFP to the rail. I asked what procedure they used to time the fuel pump, and they said that because it was common rail system it didn't need timed. I told them to yank the engine again and time the fuel pump and we will see what happens. Reinstalled the engine, cranks but doesn't start... At this point they are upset with me because I told them to install the HPFP properly, and they had to R&I the engine again to do it. They scratch their heads for a couple of days and suggest replacing the HPFP. I get connected with ET and to my surprise, the common rail is building a ton of pressure now. During cranking ET is saying desired is ~4000psi, and actual is like ~6000psi quickly. I pulled the injector fuel return line from the cylinder head and put it in a graduated cylinder. CAT spec says no more than 30ml in 30 seconds of cranking, I measured 15ml. So fuel is getting to the injectors, the return is well within spec, and the injectors passed the lab testing prior to the ECM getting fried. I put channel 1 of my Picoscope on the camshaft position signal return. Channel 2 on the crankshaft position signal return. Channel 3 amp clamp on injector 1. Channel 4 amp clamp around the negative battery cable. The ECM is commanding injection, I got textbook current signatures from all 4 injectors using the amp channel. There is no evidence of combustion, not a single puff of smoke from the exhaust. I pulled the glow plug from #1 to see if there was any fuel coming out of the cylinder when cranking. It's hard to tell, I put a white piece of paper over the glow plug hole out of desperation, didn't seem like any cherry fuel was coming out. At this point I think the engine timing is still suspect. I can tell from my waveform that injection is happening on a compression stroke. But I haven't confirmed the right cylinder's compression stroke. If anyone has a known good capture I can compare mine against it would help a lot.

Yeah I know bad me idea, but what happens with a bit of ether? Will it run? I have not had the great opportunity to play with electronic diesel systems, all I need is the right books and tools, and that is $$$$ for a retired guy. But have tons of Gasoline electronics experience. Have you checked cam to crank correlation? Do they use VVT on these?

TBH my first suspicion is that the HPFP is not timed correctly. This is something that has happened with annoying frequency on these engines. Do you have any idea how they did the timing.? For example was the front timing cover removed.? The procedure is a bit different than what would normally be expected because it doesn't use TDC on #1 cylinder to set timing.

chidog said: Yeah I know bad me idea, but what happens with a bit of ether? Will it run? I have not had the great opportunity to play with electronic diesel systems, all I need is the right books and tools, and that is $$$$ for a retired guy. But have tons of Gasoline electronics experience. Have you checked cam to crank correlation? Do they use VVT on these? Click to expand... Nothing wrong with some ether! But no I have not tried any. That is what I am trying to confirm now without pulling the engine again. They don't use VVT. Nige said: TBH my first suspicion is that the HPFP is not timed correctly. This is something that has happened with annoying frequency on these engines. Do you have any idea how they did the timing.? For example was the front timing cover removed.? The procedure is a bit different than what would normally be expected because it doesn't use TDC on #1 cylinder to set timing. Click to expand... From what he told me, he found a Kubota manual and used it to time the engine #4 piston was at the top of the stroke, and both of the rockers were loose so he lined up all the dots on the front gears. I didn't get an opportunity to check the work. I wanted to confirm the timing myself, but it looks extremely annoying to check, and fix without just removing the engine again. My plan is if no one can help me out with a 'known-good' cam/crank correlation waveform, to take another capture with Pico, this time with the glow plug out, and see if the injection event is happening on the correct cylinder. With the glow plug out my battery terminal amp waveform should have a lower peak during #1 compression, and if that's when I get the trigger for the injector, then at least I know the injection is happening during compression.

Bullitt said: Nothing wrong with some ether! Click to expand... I would try that right now. If it fires up on ether then that confirms the most probable cause of the no start is that the pump timing is wrong. There is a timing procedure that AFAIK does not require the engine to be removed (although it’s a lot easier to do it with the engine out) but it does need the timing cover and the small inspection cover on the flywheel housing to be removed in order to do it. I must have it somewhere. EDIT: See attached.

I know the guys that were working on it tried to get it to bark with ether, but I'm not sure if they were successful or not. I am blanking on their remarks ATM. I will try myself tomorrow. Thanks for the timing procedure. I keep getting my brain in a knot trying to wrap my head around it. The issue is step 1, verify #4 TDC. That would be all well in great if I knew the engine was ever actually in time to begin with. Because in order for the ECM to correctly identify crankshaft position, the crank/cam -> cam/idler -> idler HPFP needs to all be correct. As far as I can tell the crank position is based off of the tone wheel on the fuel pump, and cam timing comes from something on the cam gear but IDK where. It's not obvious looking at the parts anyway. Looking at my Pico capture I can see the RED waveform that I assumed to be the cam timing has a single window, where the BLUE as a double window every 2 RED single windows. I interpret this as the RED being 1:1 with the crankshaft, and the blue being 2:1 with the crankshaft (camshaft position). To strengthen to my hypothesis I found another manual that outlines another timing procedure that has the tech measure TDC off of #4 valve run-out and a special tool for reading the rising edge on the HPFP tone wheel. If the engine fires 1-3-4-2, I am taking a guess that #1 injector is firing during #3 compression. A guess based off of the single window crank/ double window cam being #4 TDC compression. I think I will run another capture with Pico tomorrow with the #1 glow plug removed and see if when #1 injector event is during a strong or weak compression stroke. If it is weak it's firing at the correct time, if it's not when the timing is off. If the timing looks correct, I'll remove the injector connectors and give it the ether and see if it barks. If it barks, I'll remove the injectors and send them to the local lab to get tested. I just have a hard time believing the injectors went bad when the ECM fried. Electrically the current waveforms look pretty damn good. Of course that doesn't confirm the mechanical function, but they tested fine during the engine changeover, and I don't think the torture the ECM went through would damage them mechanically. And the injector return test indicates that the injectors are indeed getting fuel too them, judging from the rail pressure it should be enough for atomization as well.

This timing instruction was in SIS, but appears to be a copy from another manual.

Bullitt said: This timing instruction was in SIS, but appears to be a copy from another manual. Click to expand... This is a Special Instruction, not a Test & Adjust procedure. Note the text - "If the crankshaft, gear case and/or crank gear are replaced". ....... and goes on to describe a procedure to re-calibrate the injection timing. That doesn't apply to you provided none of those components have been replaced. Question: Did the guys who worked on the engine before you have the front gear cover off at any time.?

Bullitt said: If the engine fires 1-3-4-2, Click to expand... It does. Bullitt said: I am taking a guess that #1 injector is firing during #3 compression. Click to expand... How so.? #3 and #1 cylinders are 180 degrees of crank throw apart. When #1 and #4 cylinders are at TDC then #2 and #3 are surely at BDC. If #1 injector is firing then surely that would indicate #1 cylinder would be on the compression stroke because it is firing.?

Also verify the buterfly is opening on top of the intake manifold. Pull the boost hose, shine a torch down and do an Air System Motor Valve Test (or something to that effect) in ET. Never trust that the test says successful, need to physacally see it move. Also try firing it up with only one of the two speed sensors disconnected.

Nige said: It does. How so.? #3 and #1 cylinders are 180 degrees of crank throw apart. When #1 and #4 cylinders are at TDC then #2 and #3 are surely at BDC. If #1 injector is firing then surely that would indicate #1 cylinder would be on the compression stroke because it is firing.? Click to expand... As Nige said the cylinders are firing 180 degrees apart, so the next one to fire after #1 will be #3 and will take the crank 180 turn to get there. And as Chrisso said try to see if it will fire up on one position sensor ( cam or crank )at a time as I did see this on a video and it found a bad sensor. Seen a video where the computer had to have a relearn to know where top dead center was. Not sure if it could apply to this thing. Simon C

Oops missed your recalibrate part in your test above Nige, but was wondering about the same thing. Simon C

Nige said: This is a Special Instruction, not a Test & Adjust procedure. Note the text - "If the crankshaft, gear case and/or crank gear are replaced". ....... and goes on to describe a procedure to re-calibrate the injection timing. That doesn't apply to you provided none of those components have been replaced. Question: Did the guys who worked on the engine before you have the front gear cover off at any time.? Click to expand... I believe they did have the rear apart. The guy that timed the engine the second time it was out said he had the flywheel and rear case apart to set the timing. It's hard for me to say concretely what was done to the engine, it was seemingly completely haphazardly bolted together with fingers crossed it would run, and I wasn't in the shop when the work took place to oversee it. Thinking again, I wonder if the crank gear turns the idler gear that turns the camshaft gear on one side and the HPFP on the other. I took another capture this morning with #1 glow plug removed. I think it is conclusive that the timing is off. #1 injection even happens on a compression stroke, but judging WHICH compression stroke based off of the current waveform, it certainly isn't #1.

Bullitt said: I believe they did have the rear apart. The guy that timed the engine the second time it was out said he had the flywheel and rear case apart to set the timing. Click to expand... Why would they have the flywheel housing apart when the timing gears are at the opposite end of the engine.? That’s not logical. The only thing that’s on the flywheel is a TDC mark that is accessed through a small cover on the right side of the flywheel housing - left side as it is installed in the machine. It’s used as a belt & braces to check the timing gears at the front. For the avoidance of doubt the engine installation in this machine is what I would class as “backwards”. The front of the engine is what you are looking at when you open the engine compartment door. The rear of the engine is bolted to the hydraulic pumps.

Nige said: Why would they have the flywheel housing apart when the timing gears are at the opposite end of the engine.? That’s not logical. The only thing that’s on the flywheel is a TDC mark that is accessed through a small cover on the right side of the flywheel housing - left side as it is installed in the machine. It’s used as a belt & braces to check the timing gears at the front. For the avoidance of doubt the engine installation in this machine is what I would class as “backwards”. The front of the engine is what you are looking at when you open the engine compartment door. The rear of the engine is bolted to the hydraulic pumps. Click to expand... The crank pulley, water pump, alternator, etc face towards the rear of the machine, so you see them when you open the rear door of the machine. The other side that I have been referring to as the back is where the flywheel, starter, HPFP and hydraulic pumps are located, this is the end where all the timing gears are located (crank gear, cam gear, HPFP gear, idler). The tech timed the engine to the cylinder towards the "rear" but the WSM they had for it (even though it is a T5 engine WSM, it is the same as my T4 TSB) looks like it shows #4 as the cylinder closest to the flywheel. I give it a shot of ether and it started running!

Bullitt said: I give it a shot of ether and it started running! Click to expand... So someone was telling porkie pies when they said it failed to fire even with ether.

I pulled the engine back out and tore the timing cover/rear structure apart. Timing was off as well as so many other issues I'm glad it didn't actually start. It will be a couple of days waiting on gaskets, misc hoses, fasteners etc. Once I slam it all back together and confirm it runs correctly I'll post some detailed pictures of the timing since the service manual isn't as detailed as I like and a good waveform in case anyone needs it.

We will eagerly await the results, and some pictures sure would help. Thanks Simon C

Bullitt said: Once I slam it all back together and confirm it runs correctly I'll post some detailed pictures of the timing since the service manual isn't as detailed as I like and a good waveform in case anyone needs it. Click to expand... That would make an excellent future resource. Kudos.

I finally got time to reinstall the engine and it fired right up. The timing diagram I attached is for a V3307-CR-TE4B and V3307-CR-TIE4B only and was slightly hard to find. Other 'generations' have dissimilar alignment marks. If you look at the good & bad waveforms long enough, I think it is conclusive that injection events were firing on exhaust strokes, the cam was correctly synced to the crank which is why there was good compression, but with the crank position being inferred from the reluctor on the HPFP, the ECM was being fooled. The engine runs surprisingly well, I ran it through some paces to break it in and all is well that ends well.