Lister LR1 injector pump

Hi everyone!

I'm suspecting issues with the diesel pump in my LR1. Seems like the 'start/run/stop' lever isn't making it any easier to start.
Can anyone advise on a simple test to check its operation, before I decide to strip it down to replace the element?

Thanks in advance, take care All!

Hi, I'm not an expert on diesel engines but have had some experience of them, One thing you could try is to undo the pipe to the injector and turn the engine over and see if you get any fuel coming out! Try the lever in different positions and see what happens!
Hope this helps!

That's kind of the way I was thinking. Do you suppose there should be a discernible increase in fuel output with the lever in the 'start' position?

I was thinking that if you tried the lever in different positions (start/run/stop) and nothing comes out, you could then look at fuel supply to the pump. Filter or supply line could be partially blocked!
Does the lever move freely and move all the way to the start/run/positions?

Ah, that's the interesting part... the engine runs fine, it's just very sluggish to start. It seems to me as if the 'start' position doesn't do anything to help. I'm pretty sure it used to be easier, but with our seasonal temperature changes there's an element of doubt.  Which is why I'm here, hoping for a definitive test

Oh, and fuel supply restriction is my other 'best guess', so a new fuel filter is already on its way.

Do you prime the engine before you start it?

Absolutely! I'm certain it wouldn't start at all otherwise.

Yesterday I tried starting it without setting the lever to 'start' and sure enough, it fired up sluggishly on the second attempt, exactly the same as the previous day (when I did set it to 'start')
Looking forward to trying it with the new filter...

How are you trying to start the engine..... are you swinging it by the handle or has it a starter motor/battery.....???
The fuel lever needs to be over in START position to START then engine. Is it marked Start,Run,Stop.??
If it has a run position then move lever to run to start and when engine fires and is running keep it at run. If it has no run position leave it at start position.... so really just run and stop positions. If you had the covers off you would see the fuel rack moving from one side to the other.
Has the engine a decompressor lever on the top rocker cover of engine. This lever holds the inlet valve OPEN to allow free turning for swinging or battery cranking. If turning with handle and this lever holding inlet valve open, the engine should be FREE to turn easily and if fuel is in the start position you should hear a SQUEAK of the injector as you turn the engine over. If there is no SQUEAK there is NO INJECTION and look for Blocked or Water in fuel filter or lines and bleed the lines etc.
Once you get SQUEAK then the DECOMPRESSOR lever on top of engine needs to be pulled over QUICKLY (to allow inlet valve to close quickly) while you are turning the engine over at a good rate and engine should fire promptly and run.

I mis-read your post, Is it testing the injector only is your problem...?
My last post is OK for check on is engine getting fuel and is injector injecting.
If going to test injector you would be better first open the covers to get inside and make sure the fuel rack mechanism at the pump is all working and pump has fuel at the bleed screw. To test the injector you will have to remove the injector an fit a pipe to re-connect it outside the engine so you can see the spray. Use an old pipe or one you have bent for the job, don't bend the engine pipe or you may not get it to seal again and leak fuel into the engine. First check and make sure pump is pumping fuel and building pressure, then with all connected up tight you should be able to see the fine mist spray from the nozzle and clean shut off no drips when under pressure as you turn the engine over with the crank handle. If nothing is happening or leaks and dribbles, then probably need pump and injector tested by diesel specialist.

Hehe, glad it took me a while to get time to reply!
First, thanks for your willingness to give such detailed advice, I really appreciate it.

Ok, let me clarify where I'm up to.
The engine is our backup power supply (12 volt off-grid home) when winter days are too short for solar panels. Last winter it ran fine every time, with some pre-warming (Webasto-style air heater) on really cold days (-10°C and colder).
The 'start' position was always used and there was a noticeable change when switching it to 'run'.

Problems began this autumn, took the opportunity to strip it down to the crank, cleaned and checked the bore, bearings and rings. All was good. Checked the spray from the injector which also seemed fine. Decided the trouble was fuel starvation (lots of flakes in the tank and fuel line before the filter).
After re-building, all was well but it seemed to me that starting was about the same, regardless of the 'start/run' position. As the temperature has dropped, it's become harder every day (of course). Once it's running, everything still seems fine. I'm just not used to having to get the heater going when it's only -3°C.

My first though was the filter might be slowing supply enough to cause the issue, but letting enough through for normal running.

So, new filter ordered, I came here to see if there's an obvious way of checking if the pump element might be suspect (in case the new filter doesn't magically fix the issue).

You could check the fuel flow through the filter on a cold day before startup by disconnecting the fuel pipe on output side of filter or removing a bleed screw on outlet side. You should have a good full bore flow and no air bubbles. Does the diesel "gel up" or "freeze at these temperatures, you may need fuel or filter to suit the condition. What head of fuel have you from the tank to the engine. Is it just a engine mounted daily tank..?. I imagine if engine runs at full load with cold -10 deg. diesel then the filter is probably letting through enough fuel. It would at least start if filter was partly blocked but may not run.
Water in the filter would be worse than dirt, and water would freeze.
Are you sure the fuel rack is moving freely, and governer is working and all adjusted. Do you get a good injector "creak" when all is cold.

Thanks again for taking time to engage with this.

So, update time...
The temperature has risen again (mornings around +1°C) and I've had much better luck getting it started.

I'd not thought about the injector sound before, but thanks to you I was listening for it this time and heard it clearly with the lever in 'start' position, but not in 'run'. So it seems the lever definitely changes something after all!

I guess the upshot of all this is that I've forgotten since last Winter exactly when it's time to start making use of the air heater. I should probably put a note in the 5-year diary to get it ready before it hits -5°C !

Since you asked; Yes, it's a small tank on the engine (plastic, not original). And I believe the governer is happy, it always seems to adjust quickly when I engage and disengage the load (100A alternator, operating around 80A with the engine set for 900rpm)

Thanks again for helping my critical thinking (and not panic-buying pump components!)