EFI to manual injection pump conversion issues

Joined
Dec 21, 2017
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Hi Folks,

I'm hoping someone here can help me sort this.

I have replaced an EFI pump with a manual pump, I am somewhat new to diesel injection and I'm having problems.

I'm working on a 92 Hilux Surf with a fresh 'early' 2LT motor, I have installed a pump from a 3L.

The problems:

It is a little hard starting and smokes just slightly at an idle, it idles just fine, as soon as I advance the throttle it runs rough and smokes like mad.
How do I identify the problem(s) and repair them?

I can and will add any data anyone needs to help me, I just need to know what to share.

Thanks very much in advance.
 
Joined
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Messages
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Thanks for responding.

I think the timing is fine (set it with a dial indicator), RPM is a snap so that isn't a concern.
I simply installed the pump (it was used) when I got it, I'm not sure I know how to "Check the injector cracking pressure", the injectors worked fine on the motor I took out.
The engine is a fresh rebuild with zero hours on it, compression I should hope isn't a problem.

I think the first issue to address is the rough running at high RPM and the huge cloud of smoke it yeilds at high RPM, the starting problem would be the last thing to work out if it didn't clear up with a fix for the rough running and smoke issue.

Thanks again
 
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What exact engine (year/model) are your injectors out of? And what exact engine (year/model) is your pump from? I think rosco is onto something. I'm willing to bet the pump pressure is not matched to the injector pressure. If they're not the same, it totally throws injection timing and volume.

If you can find the Denso part number on the side of the pump (on metal tag), that will tell you the crack pressure the injectors should be at. Tell me what your injectors are out of and I can tell you if they match or not. In any case, the injectors can be re-shimmed to match the pump. You'll have to send them away to a rebuild facility with specific instructions.
 
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Hey Nick,
Thought you where on vacation.
This is the Surf with the early model 2LT I couldn't use the EFI pump on we worked on last fall.
Snow finally left and I'm back at it.
The injectors are out of the 2LTE and the pump was off a 3L, sounds like I have another mis-match.
Would new 3L injectors be worthwhile?
I have no idea were to send these for shimming.
 
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I'm trying to take a break from Ih8mud, hence the vacation thing. I made the mistake of logging back in and seeing all these threads. Hard to break old habits....LOL.

I think the early model 2LT uses totally different injectors than the 2LT-II/2LTE/3L. You have the rocker head 2LT right? Can you see the part number on your injection pump?

OK, so the crack pressure for the early 2LT injectors from the manual is 1636-1778psi (new nozzle). Crack pressure for 2LT-II/2LTE/3L is 2148-2262psi (new nozzle). So totally different.

Ideally you should have early 2LT injectors and an early 2LT injection pump (assuming you have the early 2LT long block). Now you actually have the later injector and the later pump, so the pressures should at least match between them. However, I do know that the early 2LT injectors are totally different than the later ones. So it could be the geometry of the injection in the precombustion chamber is not right. In fact I didn't know they'd even screw into the cylinder head now that I think of it. Which makes me wonder if you really do have the early or late cylinder head.

Can you post a picture of the injection pump ID plate and the top of your engine (so I can positively identify it)?
 
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Nick,

Your I8mub habit is our salvation, at lest your help has been a blessing to me.

I can't get a camera into a location suited for a pic, I did use a mirror and got the data off the plate.

Toyota
22100-54860
VE4/10F2050RND494
096000-4940
08400098
Denso

I pulled the heat ex-changer off so the head was a little more visible, I hope the photo is helpful.

Thanks as always, Allen

IMG_2019-05-15_09-47-01_1.jpeg
 
Joined
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Hi Allen,

OK, your injection pump is definitely from a 3L. As you say, your injectors are from a 2LTE. Your cylinder head is definitely the 2LTE/2LT-II/3L style (the later style with the shim over bucket).

I'm a bit confused, because I seem to remember your engine core being the early 2L-T? Anyhow, I guess that doesn't matter at this point, as it's the injection pump and injectors that you are concerned with. And your injectors are a match for your cylinder head.

So I spent some time looking up part numbers for 3L vs 2LTE injectors. Turns out they are a different part number after all. So it's possible your problems are because your injectors are not matched to your injection pump. But I'm not sure....

Maybe do a little search on the Aus Surf forum to see if 2LTE injectors are known to be compatible with the 3L injection pump. Those guys would know for sure.

Cheers,
Nick
 
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Joined
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Hi Allen,

I might be over analyzing this. One other thing I should ask, is did you time your injection pump per the manual procedure with a dial gauge indicator? It could be your symptoms are simply your pump timing is out. Or even your timing belt a tooth off on the injection pump. One thing you could try doing is loosen the pump bolts and advance the pump a bit and see how it runs, or retard it a bit. See if there is any difference. Also check for air leaks etc. Sometimes it takes a while for them to get worked out.

Cheers,
Nick
 
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Nick,

You recall correctly, the block is early model, we came to that when the flex plate bolt pattern didn't match the crank.
That was the tell I had a motor without a crank sensor and here we are sorting the manual pump.

I did 'time' the pump with a dial indicator, but I hear all it takes is a degree or two out and you have problems.
I have a number for a fellow in BC that has a manual pump on a 2L-T, he has done a boat load of mods to his so I'll call him and see if he used different injectors. No mysteries that way.
I'll let you know what he says.

Thanks again
 
Joined
Mar 23, 2012
Messages
5,187
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Nick,

You recall correctly, the block is early model, we came to that when the flex plate bolt pattern didn't match the crank.
That was the tell I had a motor without a crank sensor and here we are sorting the manual pump.

I did 'time' the pump with a dial indicator, but I hear all it takes is a degree or two out and you have problems.
I have a number for a fellow in BC that has a manual pump on a 2L-T, he has done a boat load of mods to his so I'll call him and see if he used different injectors. No mysteries that way.
I'll let you know what he says.

Thanks again
Allen,

Sounds like a plan. One thing I should mention, is I re-sealed a 2LT-II injection pump for a friend in October last year. When he put it back on the engine he just matched the marks on the pump ear to the front timing cover as accurately as possible by eye. Truck fired up and ran perfect without further tweaking the timing using a dial gauge etc. Could be luck, or could be it's not as sensitive as some people make it out to be. Food for thought I guess....
 
Joined
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Messages
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Hi Nick,

I heard back from my contact in BC, he used his 2L-TE injectors with his manual injection 3L pump.
He did have some kind of "compensation" made to the pump, so I wonder if this is an issue that can be addressed from either end, that is to say adjust the pump or change the injectors. (Or if this is the problem in the first place, read on please).
Another fellow I checked with back in Virginia suggested that the engine will run 180 degrees out, or, it will run on the exhaust stroke. Not sure if I screwed things up that bad but I suppose anything is possible.
In the end the only person that can sort this is me, I just don't know where to start at the moment.
Any suggestions?
 
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