An update...
When I left you, I'd just finished getting it turning over, albeit slowly, and had been swapping wheels and pumping up tyres. A proper survey of all the wheels and tyres I have shows a typical fleet vehicle mixed bag of rims and tyres. I have four different types of wheel; two different two-piece rims (scary), with riveted centres, some three-piece ones (less scary), and by some strange good fortune, a total of seven matching three-piece welded centre rims, which will be the ones I use. I also have a mix of tyres, not just makes, but sizes too. My original truck had one 7.00x20 and one 7.50x20 on the front, and four 8.25x20 on the drive axle. All buggered, but five of them appeared to hold air. The "new" one had a pair of 7.50x20 on the front, and two of each 7.50x20 and 8.25x20 on the rear. Again, all buggered, but four of would at least stay up.
I had a day at the wagon last Thursday, so thought I'd get the heavy work out of the way first thing before things got too hot. I was greeted by this:
Which the sharper amongst you will remember is the first one I changed a few weeks back. Oh poo. Still, this is the "odd" 7.00x20, which is why it looks a little lost on the arch, and I'd planned swapping it for one of the 7.50s from the rear axle; so I set to:
I then finished the passenger side rear two, which I'd not had time to do at the last visit. So she's now sitting on six inflated tyres, all 8.25s on the rear, and 7.50s on the front. They're all kippered as I say, but they'll do as "rollers" while I get the back of the project broken. New tyres are going to be one of the biggest expenses I'll have to look forward to. I'll need seven really, and they're a smidge north of £200 each. Gulp.
Still, they're a pretty critical component, and the lorry is going to be capable of performing way beyond it's original limits, so when the time comes I'll have to bite the bullet.
Next job was another crack at getting it running. In the time since my last visit I'd sorted out a set of temporary battery cables, so the jump leads could be relegated to reserve. I got the battery hooked up properly and the resultant cranking speed was markedly improved. Then I pulled the injectors out and put few ccs of diesel into each cylinder and turned the engine over by hand to work it around the rings in an attempt to free off anything that was stuck. I then refitted the injectors, gave it a quick snort of easy-start and turned it over...
It tried to go! Ha Ha!
However, it didn't
actually go. Further removal of the injectors showed they weren't doing any injecting, despite fuel getting to them. Poo again.
So. Next step what? I didn't want to spend the significant cost of getting injectors reconditioned on an engine I plan removing and selling on; so what did I do?
I'll tell you, but you must keep it to yourselves, because most diesel experts want you to believe you can't service these things yourself and, if you try, the world will end. Worse than that, all the nuns and goldfish will die first! :eek:
Armed with the removed injectors I returned home. Here's what one looks like:
As you can see, it's caked with carbon, and generally a bit grotty. It's vitally important that you have somewhere totally spotless to work. Even the most microscopic bit of dirt will kill a nun or a goldfish. So the first job was to clear and scrub a bit of workspace at the bench:
My garage is currently a total mess, my apologies. Still, I did take the precaution of working on some clean kitchen roll (lint free), and scraped a bit of that muck to one side. All joking apart, it's important to keep the bits clean when you are ready to assemble them, but you've got to get them clean first.
After a quick wire-wheeling to get most of the grot off we're left with this:
Being a direct injection engine, these injectors don't have the really vulnerable needle sticking out of the bottom of them like indirect injectors do, instead they've got several really tiny holes around the nipple at the end.
The top cover here:
We are going to leave well alone. Under here is where you adjust the spring pressure that in turn governs the leak off pressure. This is the bit you need specialist equipment to set and check. I'm making the assumption that this pressure is going to be OK. Maybe not 100% within factory limits, but close enough to get the engine running again. If you were going to be fitting new nozzles then you'd want to get these pressures checked, particularly on an engine you were planning on relying on, but in extremis the tolerances on these things are high enough that for a "bush repair" you can just sling in a new nozzle and get them checked when you get back to civilisation.
However, I digress.
The bit we're interested in lives under here:
You need to hold the injector body in a suitable vice, careful not to damage the threaded boss the injector pipe fits on to. Thus:
A big adjustable spanner, because these are normally
tight (and these were no exception):
Unscrewing the collar and removing it and the needle reveals this:
The centre hole is where the spring pushes down onto the needle, the two offset pegs are to make sure you can only reassemble it the right way, and the small hole between them is the passageway through which the diesel flows. You can remove this bit from the vice now, and give it a good clean off with a bit of kitchen roll. Beyond blowing through it, to make sure the passageway isn't blocked, there's nothing further to do with this part for the time being, so put it carefully to one side somewhere it can't get dirty.
Next we move on to the nozzle and needle:
Clean any further carbon off the end, that disassembly has revealed, wipe off any dirt or muck, and make sure you've got no gritty debris on your fingers. If you look at the end that mates with the top part of the injector you should see this:
There's the two holes for the dowel pegs, and the smaller hole for the fuel to pass through. The pin sticking up in the middle is the end of the needle. This is the bit that opens and shuts the flow of fuel to the engine, and should slide freely in and out of the main body of the nozzle. As expected, this one is stuck firmly in place and won't come out, even when gripped with a pair of pliers. So we resort to slightly more brutal tactics:
Holding the pin in the vice, and gently tapping the body with a small hammer. Don't worry, these two components are made of extremely high quality material and you're not going to damage them. Trust me. Well, not unless they're seized together beyond any salvage anyway.
This method freed the pin and this is what it looks like:
It's hard to see in the picture, but the pin is discoloured with a yellowy varnish/residue which, given the very tight tolerances between it and the body of the nozzle, is enough to jam it solid and stop it opening. What is good though, is that the tip is still sharp and unworn, so there's good reason to believe the injector will work properly once the work is done. Next step is to remove the residue from the pin. You can use a solvent like acetone (nail varnish remover) and a wooden stick, but I used a bit of clean diesel and some very fine wire wool. Again, the experts will tell you that you'll destroy the pin this way, but in practice it's so hard you stand zero chance of damaging it. Don't use an abrasive like emery though. Once cleaned it should look a bit better:
Now, there's no real way of cleaning out the inner bore of the nozzle. You don't want to get any debris in there, and the holes in the end are truly tiny. make sure they're clear by blowing through the body (clean it first, diesel tastes foul; admittedly not as foul as brake fluid, but still...). If you can't blow through yourself, then use an air line, but you should be able to do so by "hand" so to speak. Next, make sure the pin is clean and put some fresh clean diesel or thin oil on it. Then work it in and out of the body of the nozzle until it is free and easy to slide in and out by hand. I do this by holding the end of the pin in the vice again, and working the body on and off by hand.
Once you've got it sliding in and out nicely, spin it around a few times to make sure the tapered seat is clear too.
Once you're satisfied, pull it all apart again, wipe everything down, blow through the nozzle again to make sure it's still clear, then lubricate it with some fresh clean diesel and reassemble. It's worth putting a drop of light oil on the nozzle where the collar bears down on it, so that it tightens up nicely and doesn't try and twist the nozzle off the locating pins as you tighten it all down the final time:
And, once it's all back together you're left with this:
Repeat as required. Do them one at a time so as not to get parts mixed up between injectors. An hour or so's work and zero expenditure later I've these sitting ready to go:
Do they work? I hear you cry.
I don't know yet.
Well, I found out why they weren't working, fixed the problem and I now know they'll work, but I don't know if it'll be enough to get the engine running or if I'll find another obstacle to overcome. I may get a chance to get up there one morning before work next week, but there's no guarantee. If not it'll be the week after I suppose. I am hopeful though; very hopeful.
If it goes, then the next step will be lashing up some kind of temporary cooling system. I don't know if the rad is any good, but if it runs I'll bodge some hoses on it and see. If, once that's done, it holds water and doesn't leak into the oil I'll bite the bullet, drop the sump and do an oil and filter change.
More as it happens, until then, thanks for looking in!
No panic though, I've plenty of other jobs to do!
Still, they're a pretty critical component, and the lorry is going to be capable of performing way beyond it's original limits, so when the time comes I'll have to bite the bullet.