4JB1T match injector nozzle to pump

[Neilg]

does anyone have any info on matching injector nozzles to injector pump for a 4JB1T? I just replaced my old pump with a rebuilt (by shop) 104741-5810 (i had a spare 5810 for exchange). The old pump appears to have been rebuilt at some stage (it was leaking like a sieve when I got it) and restamped but it was not a 5810. It was off a 88 UBS55 which ran well but needed a rebuild - the vehicle had 580,000 kms on it - which I've done. I put new but same size nozzles (p/n ends in 0550) on the original injectors, they pop at about 2600psi and give a good spray pattern, but I can't get the fueling right - eg normal power gives too much smoke, 'normal' smoke gives too little power. boost is pretty right, suspect exhaust back pressure might be a bit high (el cheapo muffler), but also suspect the nozzles are the wrong ones for this pump, which I think is off a 93 rodeo (got the pump off a spare motor). I'd be grateful if anyone has any info on matching nozzle size to pump for these motors. PS am former diesel fitter from long ago but not injection specialist. cheers.

[geeves]

engine manual here
http://www.mediafire.com/view/?32re54asslnsupk

Might help.
My thoughts are timing correct, Other settings in the pump correct, Other engine issues like compression valve timing etc

[Neilg]

thanks Geeves. for the manual link too (though I've downloaded it about six times before - I keep thinking it's a new one every time! :>) probably worth doing some of the other stuff (less restrictive exhaust, put on the turbo I have ready to rebuild, etc - never enough time) and then messing with pump and nozzles to see if I can get it right. though I find swapping nozzles is easier, at least it's mostly inside work, unlike working outside in the freezing cold. if anything comes of it that might be of interest to others, I'll post it - fueling seems to be a regular topic.

[geeves]

I know little of the workings of these pumps but do know there is an adjustment to pump length inside the top cover that could be worth playing with.

[Neilg]

here's a link that describes stroke adjustement. there's others, but even though it's for the VE pump as set up for landrovers, I found this link useful and might try some adjustments at some stage. http://www.landroverweb.com/Pdf-files/T ... _Rev_2.pdf if I can't find a nozzle setup that matches the current settings, there will be a balancing act in there somehow that should get it close. if I'm barking up the wrong tree, it's a good learning experience if nothing else.

[Roderunner]

It is very easy to get the pump or camshaft timing wrong when fitting a different pump, so if you run out of options it might pay to have another look at the timing marks, and while your'e there make sure that you are using the inj.pump cog that came with the pump as there can be small variations in the timing mark/keyway slot in various year/model pumps. Are you aware that the injectors have to be "clocked" correctly?...they have a mark on them to make sure that they are spraying in the right direction inside the chamber. I have experimented with various injection pump cold start solenoids to see what the results would be, there is usually a fair bit of difference in cold advanced timing compared to hot timing, so if the unit is not operative that might be part of the problem.
I use the color of the exhaust smoke as a guide to what's going on inside the engine, blue smoke usually points to late initial injection timing, black smoke points toward too much injection stroke or possibly (but unlikely) too much initial advance. If the camshaft timing is out (unlikely) - blue smoke below 3000 revs=retarded camshaft timing, black smoke from 2000 revs up =advanced camshaft timing.
An injector line (or a pair of) that is inadvertently connected to the wrong injector can make a lot of smoke while still allowing the engine to run on all 4 cylinders, don't ask me how I know this! Something as simple as an air leak at the hand primer pump can also cause the pump to malfunction enough to cause blue/black smoke. Checking these things should keep you busy for a while!

[geeves]

thats a very good answer with one error. This is a 4jb1 direct injection and the injector nozzles point straight down. No alignment marks. The alignment only applys to the indirect 4jg2 and getting it wrong causes big issues

[Roderunner]

Good point Alan, I should have looked into the injection nozzle spray pattern more closely before assuming a probable cause of excessive smoke! As it turns out, there are at least 6 injector nozzles listed for the 4jb1 &4jb1t. The nozzles in the Australian spec 4jb1t supposedly have 4 tiny injection holes which should point towards the corners of the square combustion chamber built into the piston. I happen to have a dismantled 4jb1t in my shed, so I cleaned up an injector and tried to spot the 4 holes. Unfortunately my eyesight isn't as good as it used to be, but I'm pretty sure that it does have 4 holes, yet a previous workshop manual that I had on my computer showed an injector nozzle with only 2 holes...possibly from the n/a 4jb1 (although it was listed under the 4jb1t heading) . The fact that there are at least 4 different workshop manuals available online only serves to confuse the issue, for instance the Europeon 2.8 was listed as having a 2600 psi injector pop pressure, yet the Argentinian delivered engine had a 3000 psi pop pressure, and the variety of different specs doesn't stop there. Maybe Neilg can pull an injector out of the engine and compare it to the original one, which will take at least one variable out of the equation!

[geeves]

Neils is Jackeroo so Ausi spec. This should be the same as the early 4jb1 with gear drive not the belt drive in our bighorns and Mus. Even so from memory the injectors out of my 89 bighorn Im sure had 7 holes. Incredibly small holes

[Neilg]

thanks fellas, yes, i had read about getting the direction of the spray right. if I recall correctly, it was to each corner of the chamber in these square-chambered pistons, so I've tried to do that. not sure how good my alignment was but I'll check again when I next have them out. and yes, these are the four-hole nozzles, the spray pattern is clear to see in my test bottle (my eyesight also isn't good enough to see the actual holes). I also have a set of injectors with five-hole nozzles, but different needles (no spigot on top) and I understand there are some nozzles with seven. and then there's the two-spring injectors - I've got a set of them but don't have the right clamps as they're the wider version. I am tempted to get a set of the right clamps and try them as they seem in reasonable nick.

The only engine match I could get with the four-hole version nozzle p/n I have was for a n/a 4jb1, even though they seemed fine with the original setup on this turbo version. these were the injectors originally in the engine when I bought the vehicle, but the spray pattern was pretty ordinary even after cleaning, so I just bought some new nozzles with the same p/n. I note one of the injector rebuilders advertising on the internet requires the pump number in order to match the injector settings, so there must be info out there for that somewhere - I might try the bloke who did my pump to see if he's amenable.

other tidbits:
just looking at one of the manuals I've got, the opening pressures for the two-spring injectors are well over 3000 psi for the second stage (up to 3900 for non-EGR), so I wonder if the single-spring injector might not be a good match for this pump. It's not the original spec pump - the original appears to have been re-stamped as a 104741 1423, the one I have fitted now is a 104741-5810, which I understand were fitted to rodeos.

I checked the timing, the pulley marks, camshaft, and all line up - TDC mark is actually TDC on this one, unlike some others I've read about. gear drive. current static setting is 0.5mm at 12 degrees BTDC which gets to about 1.7mm at TDC.

other variables - checked the injector lines when i fitted it and then again, to be sure (I think based on reading your advice on another post, Roderunner). and replaced the hand primer pump previously when refitting the engine, as it was indeed old and leaking. smoke is black, just more or less depending on how I adjust the fuel. mileage isn't as good as before the rebuild (9l/100km before, 10l/100km after). as an aside, this was a swap - changed from 4ZE1 with auto (18l/100km!!) to 4JB1T with manual, the diesel coming from a UBS55 which was driveable but couldn't get through rego any more due to rust, into a UBS17 with dud motor but pretty good body.

[Roderunner]

here's a link that describes stroke adjustement. there's others, but even though it's for the VE pump as set up for landrovers, I found this link useful and might try some adjustments at some stage. http://www.landroverweb.com/Pdf-files/T ... _Rev_2.pdf

Have you only adjusted the main fuel screw thus far Neil?

[Neilg]

sorry not to get back to you, I got sent away at short notice.

yes, the only adjustment so far has been the main fuel screw.