Thread: TD5 vibration 2500-3500 rpm

Applying pressure (leaning on) to the top of the motor from right to left whilst it is running, you should get some idea whether engine mounts are the culprit.

Originally Posted by zulu Delta 534

Applying pressure (leaning on) to the top of the motor from right to left whilst it is running, you should get some idea whether engine mounts are the culprit.

Thanks for this.
I had a look and poke around today. I couldn't discern any difference between the left and right mounts or anything else that looked out of place other than a couple of hoses that needed cable-tying up, including a coolant hose sitting on the RH engine mount. Both sides of the engine (top bolts of the engine mounts) appeared to be vibrating by about the same amount. I'll have a go at leaning on the engine as you suggest.
Thanks,
Graeme

I and a friend have the same problem with our Disco TD5's. Tried loads of things (exhausts, loom, fan etc) to sort mine but it's still there! would be interested to hear if you manage to solve yours

Originally Posted by jsbholden

I and a friend have the same problem with our Disco TD5's. Tried loads of things (exhausts, loom, fan etc) to sort mine but it's still there! would be interested to hear if you manage to solve yours

I'm waiting to organize to have the ecu checked for any fault codes (perhaps injectors) and ensure that the ecu hasn't lost the injector codes. Can't rush these things...

i've been down that road and no faults were stored

Graeme,

Any luck on solving the problem?

Originally Posted by jsbholden

Graeme,

Any luck on solving the problem?

I haven't persued it any further yet.

I now know it hasn't lost(cleared) the injector codes as the ecu limits the revs to 3000 rpm when no injector codes are stored. I also now understand that the dynamic balancing process monitors the variation in crankshaft speed caused by each cylinder's firing and adjusts fuel and/or timing to try to equalise them.

I'd like to monitor the cylinder balance data over the rev range under load to see if one cylinder's figure goes crazy, which might indicate an injector not up to scratch. I've been eyeing-off the Nanocom units which can show the balance figures. I can't justify spending $600 atm to maybe help solve this annoyance (even though it would end-up costing me at least $150 have it done by a LR dealer or specialist) but it might earn its keep in other ways over time, so maybe one day.

I've eliminated 1 more item by replacing the main muffler with a straight-through one but there's no difference in vibration/drone/noise. So its not exhaust hangers, engine mounts, accoustic cover, main muffler or engine fan, although the fan was never really a suspect as the noise is combustion-related. I still haven't had the cylinder balancing checked so that's probably next.