Lister Engine Forum

How to / DIY => Engines => Topic started by: SiFi on November 09, 2022, 05:13:40 PM

Title: LPWS4 Injector Pump not 'spitting'
Post by: SiFi on November 09, 2022, 05:13:40 PM
My engine won't start and two of the injector pumps don't appear to be working.  I disconnected the feed to each injector and only two were spitting fuel. What is the most likely problem, what I should do next?
Title: Re: LPWS4 Injector Pump not 'spitting'
Post by: wheelMA1 on November 09, 2022, 05:44:53 PM
Have you taken the metering pump out of the block? The plunger could be frozen in place, or misaligned in the lower spring. You could also have lower pump parts in your oil reservoir....
Title: Re: LPWS4 Injector Pump not 'spitting'
Post by: cobbadog on November 10, 2022, 02:41:50 AM
Have you disconnected the fuel lines comming out of the pumps going to the injectors then cranked the engine over to see if any fuel is exiting?

If not then go back to square one and bleed the fuel system at every point. Tank, filter in and out, pumps in then as I have asked pumps out while cranking the engine over?
If yes so far then crack the fuel lines at the injectors and then finally pull the injectors out of the head and see if they atomise the fuel. WARNING, do not put any part of your body near the atomised spray or you will be in pain and very dangerous to have fuel inside of YOU. So once you discover at what point the fuel stops from going any further then you know where the problem is. Once that is known then we can go further to find the issue.

Previous post from wheelMA1 about the pump is very relevant too.
Title: Re: LPWS4 Injector Pump not 'spitting'
Post by: 32 coupe on November 10, 2022, 02:05:10 PM

I think your engine is what is in military gen sets.
More info may be available on the "Steel Soldiers" site.
Title: Re: LPWS4 Injector Pump not 'spitting'
Post by: SiFi on November 11, 2022, 09:14:55 PM
Thank you everyone for your contributions.

I've discovered today that two of my glow plugs are dead and have ordered replacements. I removed one of the injectors and it does appear to be working now so maybe fingers crossed it just needed more time to bleed.

What I discovered today is that the fuel shut-off control only rotates a few mm and not enough to move the governer rack for the injector pumps into shut-off. I'm assuming there is no sort of interlock that I need to disable. The throttle seems to move back and forth freely.

Title: Re: LPWS4 Injector Pump not 'spitting'
Post by: SiFi on November 11, 2022, 09:16:46 PM
Thanks I'll check the site out.


I think your engine is what is in military gen sets.
More info may be available on the "Steel Soldiers" site.
Title: Re: LPWS4 Injector Pump not 'spitting'
Post by: SiFi on November 11, 2022, 09:22:42 PM
Thanks, I did take out one of the injectors that i thought wasn't working and today it was, so that was encouraging!

Have you disconnected the fuel lines comming out of the pumps going to the injectors then cranked the engine over to see if any fuel is exiting?

If not then go back to square one and bleed the fuel system at every point. Tank, filter in and out, pumps in then as I have asked pumps out while cranking the engine over?
If yes so far then crack the fuel lines at the injectors and then finally pull the injectors out of the head and see if they atomise the fuel. WARNING, do not put any part of your body near the atomised spray or you will be in pain and very dangerous to have fuel inside of YOU. So once you discover at what point the fuel stops from going any further then you know where the problem is. Once that is known then we can go further to find the issue.

Previous post from wheelMA1 about the pump is very relevant too.
Title: Re: LPWS4 Injector Pump not 'spitting'
Post by: cobbadog on November 12, 2022, 10:24:17 AM
Sounds like you are slowly finding some issues and this is promising because once you know what is not working you can fix it, one at a time.
Title: Re: LPWS4 Injector Pump not 'spitting'
Post by: SiFi on November 12, 2022, 11:49:26 AM
Thanks. Can i ask another question, my fuel shut-off seems locked in position but the throttle moves freely, are these both linked to the govenor rail? I'm trying to work out why one moves but the other won't.
Title: Re: LPWS4 Injector Pump not 'spitting'
Post by: cobbadog on November 13, 2022, 05:16:44 AM
Sorry mate that is something I do not know with certainty. You can ask as many questions as needed to get the help you need, this is how we all learn.
 However it would be fair to say that it sounds as if it has stuck and requires freeing up. Have you found a manual on this engine as yet? When we work on these things they always help explain what belongs where and sometimes how they work. Most importantly the correct description of parts too. I go onto another Forum for tractors and it can muddle everything up by calling parts by the wrong name.
Please don't think I am saying that this is the case here. Again clear pictures always help with descriptions.
Title: Re: LPWS4 Injector Pump not 'spitting'
Post by: 32 coupe on November 13, 2022, 05:27:37 PM
Google  LPWS4.......the manual will come up from many sites for download.