hdi vibration

[mjb]

Hdi90, new crankshaft pulley, alternator and belt. New top mounts and bottom mount. New cat and flexi-hose (old ones destroyed due to worn engine mounts)

Since replacing all the above, it's developed a harsh vibration when the missus pulls off (which she does without using the accelerator ) which *might* be a knackered clutch, and a lesser but very noticeable vibration when accelerating through 1800-2000rpm, which is not present in neutral, only under torque.

I'm at a loss to explain this, other than a worn gearbox mount, which I always thought did bugger all?


Thoughts?

[Doggy]

Any chance you've put the bottom mount bush in 90 degrees from the way it should be aligned? (Can't remember the 'right' way at the mo).

[mjb]

I think I got it roughly the way it was from factory - about 45 degrees from vertical. Mind you, I haven't actually seen anyone saying "yeah I put the mount in wrong so I got another and put that in right, and it cured my problem" so I think it's all a red herring

Think I'd rather set fire to the car than go through that ordeal again...

[bytecode]

Any chance you've put the bottom mount bush in 90 degrees from the way it should be aligned? (Can't remember the 'right' way at the mo).

Any chance of a "suggestive" photograph to indicate the correct orientation (oo-err)?
I assume that we're talking about the radial parts of the mount being oriented to absorb the push-pull of the engine under load?

[piglet]

mjb, did you resolve your vibration issue?

My flexi broke so I put it in for a new flexi & cat on friday, all seemed fine when I drove it home, but sat morning I did 90 miles with trailer and it developed a roughness when acceleration past 2000 rpm.
I've inspected the new pipe think it may have slipped and be touching the body but all looks well.
The exhaust guy said check the engine mounts as the busted pipe looked in otherwise good condition.
I can't see anything wrong with top or transmission mounts, I have tried rocking the top of the motor and nothing seems to move.
Wots going on?

[Welly]

I had my lower mount replaced on my old 110 HDi and the 'test' was easy:

With the engine idling simply blip the throttle; if the engine moves by any more than 15mm or so or looks like it wants to throw itself over the headlamps then the mount is shot (mine used to lurch forward by about 50mm).

With a new mount fitted the engine movement was minimal (a huge difference) this constant back and forth of the engine is what tears through the flexi pipe and then, in my case, tore through the intercooler bottom hose too 'twas an expensive week that one

[mjb]

It's nearly always knackered mounts which cause flexi-hose destruction...

Replacing the top and bottom mounts cured most of the vibration, however some still remains. I still haven't replaced the gearbox mount yet but I have a sinking feeling it might be the ebay cheapie mounts I used which are letting it down

[Welly]

It's nearly always knackered mounts which cause flexi-hose destruction...

Replacing the top and bottom mounts cured most of the vibration, however some still remains. I still haven't replaced the gearbox mount yet but I have a sinking feeling it might be the ebay cheapie mounts I used which are letting it down

Maybe ram in some old coolant hose cut-off's?

[piglet]

Had a better look at the car last night, did Welly's blip test, top didn't move excessively and the sump moved back & forth about the same as the rocker cover. Got under and dropped the under panel, the new pipe & flexi look properly installed, nowhere near the body and the the lower/rear mount looks fine visually.
The pipe was a good price, I'm wondering if it's a cheap flexi not absorbing the vibration sufficiently, bit difficult to test that.
It's bad enough that as I accelerate through 2000RPM my bunch of keys rattle slightly in the centre console, and if driving at a steady 2000 it is unacceptably noisy.