strange engine running

[Elniff]

hello in here. my Ldw 1003 has started to get strange engine running at 1560 rpm. I have cleaned the fuel system. and put new injectors in without it making a difference. anyone or have a solution.? about 13 seconds into the film it starts

Google Translate


https://youtube.com/shorts/FHa9pp2KJKQ
Google Translate

[Pete7]

Elniff,

Could you provide an English translation please so everyone can understand. Don't worry about your English the forum knows you will be posting in a second language and make allowances for you.

Regards

Peter

[skipperpete]

Elniff, it sounds bad. I’m really impressed that you changed the injectors , no easy task on that Lombardini FOCS.
It could be that the engine is shaking so badly that the propshaft is knocking in the tube, there are a couple of other threads on this forum discussing vibration ( bad vibration) with this same design so you’re not alone. Best of luck with solving the problem and it might be worth trying for a warranty claim with Lombardini... now owned by Kohler US.

[Elniff]

Could it be my fuel pump. when I get up to 1560 rmp. so that it cannot deliver enough diesel

[skipperpete]

Anything is worth a try, hook up an electric feed pump and see if it helps. The problem with your LDW is that it has a variety of ways to fail, especially in the fuel system. If you have access to a Lombardini dealership, get them to send a mechanic..... but only a Lombardini mechanic, ordinary diesel guys won’t have the service tools required, you might also contact Volpi, they use that engine in the small gensets.
What country are you in?

[Lepke]

It sounds like an injector not firing. Since you changed them, then maybe you have a leaking injector tube. If the injector doesn't get fuel near the correct pressure, the needle valve in the injector won't open. Fuel coming into the injector causes the needle valve to lift. When the pressure is low because of a leak the needle valve only lifts part way or not at all.
The other possibility is a problem in the injector pump.
An injector not opening can sound like a rod knocking. It's much more noticeable in a 3 or 4 cylinder than a V-8. It also would be why you can't reach high rpm.
I have no experience with your engine. If it's electronically controlled, the problem could be in the control circuit, wiring, a connection, and so on.

[Dave_S]

Originally Posted by skipperpete

Anything is worth a try, hook up an electric feed pump and see if it helps. The problem with your LDW is that it has a variety of ways to fail, especially in the fuel system. If you have access to a Lombardini dealership, get them to send a mechanic..... but only a Lombardini mechanic, ordinary diesel guys won’t have the service tools required, you might also contact Volpi, they use that engine in the small gensets.
What country are you in?

Originally Posted by Lepke

It sounds like an injector not firing. Since you changed them, then maybe you have a leaking injector tube. If the injector doesn't get fuel near the correct pressure, the needle valve in the injector won't open. Fuel coming into the injector causes the needle valve to lift. When the pressure is low because of a leak the needle valve only lifts part way or not at all.
The other possibility is a problem in the injector pump.
An injector not opening can sound like a rod knocking. It's much more noticeable in a 3 or 4 cylinder than a V-8. It also would be why you can't reach high rpm.
I have no experience with your engine. If it's electronically controlled, the problem could be in the control circuit, wiring, a connection, and so on.

I'm no diesel expert but I like these answers. They match with a couple of similar issues with diesels at work. It sounds like a miss-fire and it happened at repeatable rpm every time. On ours it was the injector pump not delivering enough pressure to fire the injector, exactly as described above. We fitted a stronger lift pump also described above (Holley red in our case) and the problem went away. To me this indicates that the injector pump is worn (no leaks in our case) and the lift pump is assisting the worn pump enough to fire the injector. To recondition the pump was AU$2,500 and to fit the Holley red was a few hundred. It corrected the problem but I'm sure it will come back, when it does we will know to replace the injector pump.

I would test fit a better lift pump and see if it runs properly, if so you can leave it like that untill it starts to miss-fire again (I don't know how long that might be - I expect 200 hours? but that's just an uneducated guess) or replace the injector pump straight away.

[skipperpete]

The LDW series from Lombardini combines a series of unreliable structural features with a unique fuel system that is difficult to adjust or repair.
Lombardini built an engine with an alloy head so if it ever has an overheat it’s most likely that the head gasket will be compromised and/or the head warped. In this alloy cylinder head are alloy steel precombustion chambers which adds another level of difficulty to resurfacing.
The engine has a belt driven overhead cam and the belt must be replaced after removal for any reason at any hours (or 2,500 hrs if never removed)
The engine has almost the entire fuel system under the camshaft cover.
The camshaft cover is part of the lube oil system and the engine can’t be run with it off.
The head bolts have a go/no go length so pretty much single use.
The unit injectors seem to be in house despite having Bosch parts and are totally unique.
The phasing and calibration of the injectors defeats most diesel mechanics
and finally Lombardini advertises the engine as “ the most vibration free engine on the market”.
Diagnosing a fault.... any fault on this little engine is tricky and repairing a fault especially in the fuel system requires service tools unique to only this engine.
Pete.