HELP with D40

[kezza170]

OK crew we are at an end what is happening with my D40.
2014 Spanish D40 140kw automatic.
so its been in the workshop at mechanics and its had a load of work done to it and almost everything on the bloody car has been replaced to brand new exception of a few parts.
The head hasnt been off. But the injectors i took out and sent away to be proffesionally cleaned and tested and were excellent and i took the glow plugs out so they could be replaced, took manifold of drivers side of engine and cleaned the carbon build up out was hectic tried to let bare minimum go in to engine. Has turbo replaced, radiator, hoses, starter motor, intercooler, oil coolers both been upgraded, brand new exhaust turbo back, new pulleys and belts, new alternator, battery, new sensors, air filter etc

But today i went to the workshop as they said they couldnt get the car started which is weird, so they were spraying start ya bastard in it and its making a noice which is weird sounds like blowby but it went before injectors came out and head wasnt touched, the mechanic said it sounds like a hole in the piston but again went fine before injectors came out and got towed to mechanics.

Ill attach a video of the noise

any help or suggestions would be so greatly appreciated... were desperate now as ive already spent way to much on it and now there saying sounds like new engine needed but went fine before injectors out.

 

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injector seat seal ??? if one is not sealing computor wont let it start... if you flood a cylinder with start ya bustard you could theoretically cause some damage,, if it doesnt start and you keep adding ether it will lock the motor .. if its a hole in piston there should be exessive blow back through pcv valve and you would feel it with your hand . some noise would be there on each compression stroke for that piston , shouldnt be happenning only when you stop cranking.. if its happening on each compression stroke ,any chance that copper injector seal broke and its fouling a valve or the old coppe rseals not removed properly

 

[kezza170]

the copper seals are new but as you suggest may not have been put in correctly i just sent your reply to my mechanic makes perfect sense, thank you so much for the reply to appreciate it

 

[Old.Tony]

I think if there's a hole in a piston you wouldn't achieve the compression for combustion in that cylinder, so the engine MIGHT start (on the other cylinders), but she'd run rough as hell. You'd also be slowly diluting the crankcase oil with the diesel that is being injected into that cylinder. Further, the blowby from other cylinders will be filling that cylinder on its down stroke (which could easily flood the intake manifold).

Draining the oil might reveal the fragments from the holed piston, but a better method is to use an inspection camera in the glow plug hole.

I suspect that's not it though. There was no sound of the other cylinders trying to fire, and it's super-unlikely that you've managed to punch a hole through all 4 pistons.

The injectors might be in good condition but are they opening? There's an easy way to tell.

1) Disconnect the glow plugs (40A relay is on the guard near the battery, or remove the glow connectors).

2) Prime the fuel system until the primer bulb is quite firm. You're trying to ensure that there's fuel in the system and the fuel pump won't run dry.

3) Crank the engine a few times

4) Pop a glow plug. Is it wet? Smells like diesel? While you've got the plug out, chuck that camera in and take a look in the cylinder.

I don't suspect EGR flooding because you'd have to have some combustion happening somewhere to produce the exhaust gas to flood the intake. I don't hear that happening.

Diesels are simple beasts. Inject some fuel into some compressed air and it happens.

Has the crank angle sensor been checked? Is it mounted correctly and electrically connected (disconnect it, clean the contacts if possible, reconnect) ? This governs when the injectors should open and is crucial to getting the engine started.