Hi all

i have just had my disco 300 tdi serviced with new cam belt, tensioner, pulley bearings etc. the 4 wheel bearings were also removed and greased and refitted. I now feel a slight vibration like feeling at around 100km/h. Could this be caused by any of the work done mentioned above. Your help would be appreciated.

Thanks

 

Do you get any noise with the vibration?

One quick check you can do - you'll need an assistant.

Jack each wheel up in turn and hold it in the 12 oclock and 6 oclock positions - feel for play in the bearing, there should be just enough to feel it move very slightly. To make sure the play is the bearing, get your assistant to press the foot brake down - if the play dissappears then all is well.

If you find there is more play than you're expecting (i.e. more than a milimeter or so) or that there is no play at all then that bearing is either too loose or over tight - either can cause a vibration at speed and probably a whining/groaning noise from the relevent corner. Disco 1 and Defender bearings are tapered, so shouldn't be over tightened.

If all is well there, I'd check the prop shaft UJ's and the tightness of the prop shaft bolts next.

Cheers,

 

Thanks ADZ

No, there is no noise at all. Even when the vehicle is stationary and idling, there is a slight vibration which i can feel on the steering wheel. There is also a slight drop in power.

 

If the vibration is there while you're not moving you can rule out the work you had done on the bearings and ignore the advice about propsjaft UJ's (although it's always a good idea to keep them regularly greased) as the cause of the problem.

How many miles on your truck?

 

It s got 230 000km on the odo. Motor was done at 170 000km and turbo overhauled at 200 000 km.Vibration goes away when travelling at high speed.

 

Well... I'm no engine expert, but at 230k it should have some rattles and vibrations, it's a Rover! However, the loss of power isn't to be ignored.

Re-reading your posts above, the vibration at 100kph and the vibration at standstill might not be the same thing.

For the vibration at standstill:

Things are bound to get disturbed while work is done on the timing belt, there's a lot to remove after all, you're not likely to find an absolute cause or cure for it. A new belt tensioner and bearings will need to run in over the next few hundred km's - if the problem is still there when you're confident everything is run in, take it back to where you had the work done. It's probably advisable to let them know what you've found so far and at least make them aware that you're not completely happy. Obviously, you can ignore that bit if you did the work yourself.

For the loss of power, changing the timing belt can have an effect on the pump timing - bear in mind that if the belt is as much as a tooth out then the engine probably won't even start! Once you've spoken to the people who did the work for you look to get the injection pump timing checked as a first port of call. Again, if you did the work yourself, checking the pump timing would be a good first bet.

For the vibration at speed and bearing in mind the trucks age and mileage:

If you haven't already, go check the props for play in the UJ's, sliding section and at the diff ends - might as well regrease them while you're under there as it takes moments to do.

Chock all four wheels to be on the safe side and take the hand brake (e-brake if you're from the US or Canada) off as it will lock the rear prop if it's on.

If you can rotate the prop a 1/4 of a turn with the car in gear then there's probably some slack in the diff that will only get worse.

If there's any play in the UJ's at all - then they'll need overhauling - not an expensive job, or particularly difficult to do. Best way I've found to check them is with a big flat bladed screwdriver - put the tip between the yokes of the UJ and gently try to lever them apart - if you can see any movement then they're shot, although packing them with grease might temporarily cure the problem (up to another 100kms or so).

Likewise, go check the play in the wheel bearings - you don't need any tools to do this, just your hands as described above in my first post.

Let me know how it goes

 

Thanks ADZ, will keep you posted.

 

I CAN PUT MONEY ON IT THE TIMING IS A TOOTH OUT... YES IT WILL START WITH THE TIMING A TOOTH OUT..
AND POSSIBLY A BENT PUSH ROD TO GO WITH IT.. I BET THEY DIDNT TURN THE ENGINE OVER BY HAND BEFORE THEY STARTED IT..

 

There's a chance it could be the front drive shaft. If it's a disco II, I'd bet on it.

It's a common problem... I just had mine replaced. It could be anything from bad U-Joints to an out of balance shaft. The weights welded onto the shaft tend to fall off.

 

SORRY TO SAY BUT SERIES II NEVER CAME OUT WITH A 300 TDI ENGINE..
READ THE QUESTION..