Thread: Engine Failure Driving Home - Land Rover Defender 110 TD5 1999 X-Treme

Good Morning team,

I'd very much like your learned opinions (and hopefully a less pessimistic outcome); I was driving my good old Landie home from the coast on the weekend and out of nowhere, a very disturbing knocking noise developed in the engine. I pulled over immediately and gave it a tentative rev, to discover that the knocking increases with revs.

Suffice to say I was very disconcerted by this and an NRMA Premium Roadside assist tow later, I was at my local mechanic. The NRMA call-out mechanic was the first one to deliver the heartstopping words "it sounds terminal", with the same diagnosis given to me by my local mechanic. He suggested he could have switched the injectors around to see if that was an issue (this was largely techno-jargon which went above my head however) but that it would likely have come to the same conclusion.

I don't hold out much hope, but I thought I'd post here to see if I could MAYBE get a better outcome? Landie has just clocked up 212000 and has just had a reconditioned gearbox put in it.

Thanks in advance,

Toby

Originally Posted by PhilipA

If you were only at low revs it could be that the rubber has disintegrated in the Harmonic Balancer.

I can attest from a friend's D2 that when the balancer goes, it gives a loud knock at idle.

So take off the ribbed belt, after removing the fan and shrouds and see if you can move it by hand back and forth.
Regards PhilipA

I would recommend to remove the fan belt and start the motor just to see if the knocking noise is still there.
Could be harmonic balancer(will still knock with belt off!), could be tensioner, could be fan bearing, could be alternator! .. not hard to remove belt, and you can easily run a motor without the fan belt for a good 30sec or so(maybe more when cold) for diagnosis.

Knocks could be anything .. loud, intermittent .. etc.

Strange ones that nearly got away from me:

Brother's Td5 D2. prior to servicing it for a weekend away, I hear a knocking noise. Not a thumping knock, but loud enough to be a worry. First thoughts were major damage, but remove the fan belt and knock was gone.
Fan belt on knock came back. I started to remove the tensioner, first/easiest thing to check .. and whilst hands down there I noticed the alternator moved around a lot .. for a fixed item!
Aha! .. inspecting closely the small aluminium holding bracket was snapped at the rear end of the mounting bolt, big crack at the front eye mount.
S/H mount found, installed ... knocking gone.

The other annoying knock was my Tdi: Took many months, maybe even close to a year to solve. Sounded like small end or big end bearing issue, except far too intermittent. Knock seemed to come from passengers side front of engine.
Replaced what looked like a wobbly(not perfectly round) water pump pulley .. not it! removed many fan belt items, replaced water pump(as this seemed where the noise was coming from) .. also a bit of preventative maintenance too.
After many months and some annoyance .. turned out to be a slightly too long fan belt! Being a few millimeters too long allowed the tensioner to 'bottom out' and rest stops touched .. intermittently! Cost about $15 for the new belt.

Main point is not to assume the worst, only to find out it was something hilariously simple!