defender still has pronounced diesel knock

either that or i am losing the plot,but previous lump was quiterdoes this sound like tappets or maybe injectors?i know its tick overs advanced,if i turn the fuel screw back slightly,its gutless in first and second,this is a replacement lump from a disco,my original one cracked its block,the original injectors have not been used,this engines done about 50k less than the one that was in there ,but diesel knock seems more pronounced ?,minimal smoke ,only if revved hard,so little i could not see any in the video,https://www.youtube.com/watch?v=kQY3r1SyWp8&feature=youtu.be

Have you checked the diesel pump timing?

Sounds like mine, but there is definitely a knock there at the end of the vid. Is the vac pump making any noise?

kes86 said:

Have you checked the diesel pump timing?

Sounds like mine, but there is definitely a knock there at the end of the vid. Is the vac pump making any noise?

Click to expand...

timings bang on,forgot to chuck the vac pump into the conundrum,glad someone else can hear it

Never really got to the bottom of why mine does that too. Changed lift pump, head gasket, pump timing several times, sealed up crack in brake servo (temporarily) swapped vac pump etc etc. I have just replaced the turbo to FIP boost pressure pipe, as mine had worn though rubbing on something. I joined the pipe together with a air pressure fitting but it leaked oily air, so replaced the pipe.

Since then it does seem better.

Try changing the fuel supplier .. I always use the local Tesco for instance, maybe use a different garage and see what happens. Also change the oil, move from whatever you have now to a grade thicker, see if that makes a difference. Check the exhaust manifold bolts and downpipe nuts are properly tight!

I couldn't hear any noises that pointed to anything definite.

THEengineer said:

timings bang on,forgot to chuck the vac pump into the conundrum,glad someone else can hear it

Click to expand...

Rewind here a minute, the timing is bang on in what respect?

Bear in mind the pump is designed to be adjusted independently of the belt position for a reason.

Assuming that when your engine is at TDC the crank and cam both hit the marks and the pump is right by the outer sprocket, that doesn't actually mean your pump timing is bang on.

I would retard the pump a touch - take the cover off the front of the timing case, turn the engine over till you can stick a drill bit through the sprocket into the back of the timing chest.

Then pin it using a drill bit that fits, if it's too advanced it might be a smaller drill 8/8.5mm 9.5mm should fit.

Now, loosen the just a little the bolts that locks the outer pulley to the inner flange.

Now get a socket onto the pump shaft in the middle and nudge the pump back a little this will open the gap up where your drill bit goes, try fitting in a drill bit 0.5mm bigger and then adjust it onto this drill bit so you know you have moved it by 0.5mm.

Now do it all back up and start it...

The last time I did mine, about 2 years ago, I did it by feel and kept an eye on the gap in the hole in the sprocket. I nudged mine clockwise - advanced a nudge, started it, took it for a spin, came back, tweaked it a little more, that was too much so went somewhere in the middle and was happy with that. I did it on a warm engine, not full temperature but the engine had been on it was all warm to the touch. No point having it spot on stone cold.

The important thing is to have a start point, so if all goes to hell you can do back to square one, but to be honest it cannot really go to hell. It's not that difficult, it's like doing valve clearances really. Just a little care and attention.

Could also be a knackered injector...

Just remembered, I changed my injectors too.

But, I have been filling up at another petrol station lately, as the one I usually go to is dodgy to get out of during TT, so mine could be fuel related.......

After doing my head gasket, number 3 cylinder had much more bore wear than the rest, also injector 3 looked pitted, however it tested ok.

I used to find it went quieter when I put some redex diesel injector cleaner in it.

None of this helps really though!