Hi All,

The engine won't even start now, there is diesel up to the injectors and there is black smoke when cranking but no attempt to fire. Looks like injectors need assessment. I'll let you know more when I've got them out and tested !!
Regards.

Hi,

Wow, thanks very much for the detailed reply!! It explains things very clearly. I'll check out my truck and let you know how I get on.

Regards,
Ratter.

engine timing chain
now if you want to check the timing chain inside the timing cover
Turn over the engine in the direction of normal rotation (usually clockwise (looking from the front of the engine) till the crank pulley timing mark is on TDC (on compression stroke with #1 cylinder) with the indicator on the block. The #1 cylinder rocker arms on the valves will be rocking freely with the exhaust valve and intake valve closed. Once you have this set:
- remove the timing gear cover
- check the timing chain in relation to the gears, there should be markings on the gears and there will be different colored links in the timing chain, these should align up with the marks on the camshaft and fuel injection pump gears. The crankshaft gear has a white mark. All these should be aligned when the engine is on TDC on #1 piston compression stroke.

pay attention to the fuel injection pump gear markings and make sure they are aligned, if they are not then you can at this point correct the problem.

Note: keep in mind you may have to turn the engine over many times coming up on the compression stroke to get all the gear timing marks to line up with the marks on the chain exactly.
Now if you cannot get the injection pump marks to line up when the crank and cam marks are lined up then this will tell you the injector pump was not installed correctly. At this point you can remove the pump, set the pump at the correct position, install the pump gear at it's correct position and reinstall it with the marks lined up.

-continued from previous post-

Injection pump timing
Now if he just had the pump removed and rebuilt then the timing chain for the pump should still be intact and in the correct position.
On the flange around the injection pump there should be marks/lines indicating a setpoint and the mounting holes will be slightly slotted to allow for a slight rotation of the pump assy.
(This is just for the external timing adjust) If the tech that had the pump out did it right he should have made indications where it was set so when remounting it the pump would be in the same spot. You can loosen the mounting nuts and attempt to move the pump in small increments and attempt to see if that clears up the timing problem.
If this does not improve anything then you will need to get a trained caterpillar diesel tech for this engine to come and check the fuel injection pump internal timing. It is a complicated process that requires special tools and i cannot go into explanation here.

So do all the things here (and the previous post) i explained that you can and see if you get any positive results.

Hopefully this helps :o)

ratter,
ok i found some other info about troubleshooting problems and they deal with low power issues and black or dark gray smoke.
They describe the possible causes as being:
- not enough air for combustion so check the air filter and make sure it is not clogged up, you should be able to pull it out and put it up to a bright light like the sun and see light through it. If not then replace it.

Black or Dark gray smoke
- injector nozzles (we already mentioned this)
they could have bad seal washers or could even be the incorrect ones. a possibility if they were rebuilt and he was just given the wrong ones back, hard to say.
- wrong fuel injection timing (we've already mentioned this and will check later).

Low power issues
- low quality fuel
- fuel pressure is low
- air in the fuel system
- accelerator linkage not adjusted properly
- wrong valve lash set on valves
- fuel injection nozzle defective (already mentioned above)
- fuel injection pump timing not correct (already mentioned above)

Now with all this said we can make many assumptions here that he did not do anything with the accelerator adjustments other than the connection at the fuel injector pump where the linkage connects. The only problem that would occur if the linkage was not connected correctly is not pulling the injection pump to full open which would cause it not to go to full rpm and cause a low power scenario but will not cause black or gray smoke. (we will assume the black smoke problem is causing low power issues for the moment).

So we go to the injectors and pump, we can check to see if there is any air in the system.
The fuel system air bleeding proceedure is as follows:
- Bleeding air from the fuel filter:
1- make sure there is enough fuel in the tank and it is clean.
2-On the fuel filter assy look on top of it, there should be a priming pump button and also a bleeder screw off to the side somewhere, you can pump the primer button to pressurize the lines and crack that screw, if you get any air bubbles out of it then let it run out till all the air is gone and clean fuel only is running out of it. Then tighten the bleeder back.
3- look on the fuel injection pump, there should be a vent screw on top of the body, use the same proceedure as bleeding the fuel filter, use the priming pump to pressureize the system till you get a good resistance on the priming pump, then crack the bleeder screw on the pump body and let fuel run out, if any bubbles let it run out till the bubbles are gone. You may have to continue to pump the primer pump to achieve this.
note: if this fuel system has an electric fuel lock solenoid on it you will have to use the preheat button till the light goes out, then turn on the ignition switch and leave it on so the fuel will flow, otherwise you will not get any fuel flow to remove any air. If you find any wires hooked to a solenoid on the fuel injector pump this procedure will need to be done to bleed air from the pump.

4- remove air from injector lines:
loosen nuts on top of all the injectors, move/press the accelerator pedal to full throttle position, turn the engine over with the starter motor until fuel runs out from injector lines with no bubbles. Once the air stops coming out of a line you can tighten the nut on that injector and do this for all other injectors as the air stops coming out. If you do not get any air out of any injector then tighten all nuts and stop cranking the engine over.

This is the order for bleeding air from the fuel system.

Now before you start bleeding air out you may want to do the following:
pull out each injector and check for the following, each injector has 2 washers at the base where they mate up to the engine head, there should be a large copper sealing washer and down inside where the injector seats into the head there should be a smaller thin steel sealing washer. Make sure all injectors have both of these. Do only one injector at a time so you will not mix these washers up, they should stay with their respective injectors as they have already been seated to their mating surfaces. If any of them look damaged or compressed wrong replace them.

to be continued on next post

Hi,
Thanks for the reply.
I haven't looked closely at the pump fitting, but are there any timing marks that need to align on this particular engine ? Or will they be evident once the area is cleaned up. To be honest I haven't had much chance to look at it closely but it definitely needs sorting.

Thanks in advance.

black smoke in exhaust means it's not burning all the fuel being injected into the cylinders.
So yes it could be a timing issue.
Since the previous owner claims he had the injectors and the pump rebuilt you may want to double check the timing.
The Fuel system diagnostic chart list these possible causes for black smoke:
- Fuel injection timing
- Poor compression
- Fuel injection
- Fuel injection pump

So basically you'll need to verify the timing for the fuel pump is set correctly, then check compression and if these check ok then your looking at injector or pump problems and will have to remove them and have them checked and possibly repaired.
It is possible that whoever did the rebuild on the pump and injectors did not do it correctly.