injectors rattling b****cks off!

[Dr HMS Derv Destroyer]

hi all, my new engine as been in for a while now, its got a new pump and injectors but the thing that's been playing on my mind for a while, is the injectors are rattle'n tapping loud under loud, plus it struggles to give power after 3k rpm
injectors all coded, correct type and no air in the system at all.
whats up? ecu not telling them to put enough fuel in?

 

[Dan@SJM]

Leaky injector seals?

 

[MicKPM]

Injectors leaking give a distinct noise compared to diesel knock so does it sounds like a massive exhaust blow under the bonet resulting in black crap around the injectors or does it sound like a hammer hitting metal?

 

[MG cup]

Do the DCI's have a timed HP pump?

 

[MicKPM]

Yes, the HP variants do but the dci 65/70 doesn't

 

[MG cup]

All common rail though?

 

[MicKPM]

I believe so yes. I think the lower power units run the Bosch CP3

 

[Dr HMS Derv Destroyer]

its a 100 lump with 80 injectors and HP pump.

no crap around the injectors, all torque'd down to 30nm

they sound like someone tapping on metal with a punch tool. almost like air instead of fuel in them.

theres f**k all air in the fuel pipes, it starts runs and never conks out, just rattles like hell under load and struggles to go over 3k rpm.
the engine it self sounds like its a heavy breather aswell? or is that what 100's do?

 

[MicKPM]

That's diesel knock then and not good. Does it start okay or does it need a bit of cranking? Were the injectors tested prior to installation? What's the fuel pressure like on diags?

Mick

 

[pure-motorsport]

That does sound like knock. Have you checked cam timing? Have you got any cam timing/phasing fault codes? What's the history on this engine? Is it one that has just been built up?

 

[Dr HMS Derv Destroyer]

it starts straight away no prolonged cranking.
injectors all flow and solinoid tested as soon as i got them brand new from renault.

timing is all spot on, cam locked in possition, crank key in position and fuel pump lined up with bolt.

it litterally on sound like a hammer under load and near or above 3k.
no clouds of undburnt diesl out back.

the engine is a fully recond unit from rsc , ran in properly for 1k.

i read somewere the injectors need a run in cycle? nit sure on mk2's

 

[Dr HMS Derv Destroyer]

the old engine did leave s**t loads of codes to do with cylinder possition timing ect.
this engine hasnt flagged any faults up apart from the boost warning which turned out to be a lose clip on the IC

 

[Dr HMS Derv Destroyer]

fuel pressure i havent a clue about but theres no signs of the pump struggling.

as i said , glows warm up, starts instant on the key. i'll get i video if it helps ?

 

[MicKPM]

Diesel knock is normally caused by incorrect timing, fuelling or injector control. It may also be a compression related issue but its unlikely if its starting on the button.

 

[Dr HMS Derv Destroyer]

i'll get i video up later, hats if i can capture the noise over everything else

 

[1uk3m4n]

Take it back to the garage who fitted the engine? They should be able to diagnose it pretty easy

 

[1uk3m4n]

If you ain't had it long should still be under guarantee I take it?

 

[Dr HMS Derv Destroyer]

i've fitted it at my mates garage, but he's currently away for the month hence why i've had a window to do it.

now i am not mechanically retarded so i cant really of done anything stupid.


yes engine is under guarantee aswell as the injectors and pump from commonraildiesels.com

 

[pure-motorsport]

Diesel knock is normally caused by incorrect timing, fuelling or injector control. It may also be a compression related issue but its unlikely if its starting on the button.

If it's knock the ECU must be firing the injectors at the wrong time or wrong duration. If the cam timing is correct could you have some pump pulley (cam sensor uses this IIRC) /flywheel incompatibility somewhere?

 

[pure-motorsport]

Just had another thought- I assume the oil pressure is good? If so have you checked the valve clearance - these use shims - has one dropped out?!

 

[Dr HMS Derv Destroyer]

oil pressure is bob on. havent checked the valve clearances , which could indicate why it sound like a heavy breathing inlet.

they're not shimms either, i though this but it turns out they're solid bucket tappets

 

[1uk3m4n]

You sure the bucket ain't the shim? It normally is

 

[Dr HMS Derv Destroyer]

not a clue, im sure was dan or mick that told me it was solid buckets instead of shimmed buckets

 

[MicKPM]

Not guilty your lordship

 

[Dr HMS Derv Destroyer]

Mike then?
​its not stone or his companion