starting rattle

Hi,
Have to say that this forum has been great on helping me sort alot of the problems on my discovery 300tdi that i got last week. So far i have fixed the bias plate on the gearshift, rear door central locking (bust spring and lock motor), unsized the difflock, fixed the reversing light (switch connections and a bulb) and just set the tappets. I am at the moment cleaning out the intercooler and pipes and getting the handbrake lever stop rewelded. I also have of my list of things to do, fix the sunroofs, fix the passenger side doors (Springs again), heated rear window, rear foglights (these seem to have the same problem, missing wiring and connectors, i guess they are in the dash somewhere..) and weld up the inner wings and a full service and fluids. But one annoying problem has got me stumped and cant find another thread on this.

When i start the car, whether hot or cold there is a loud rattle, which dissapearers as soon as the throttle is touched. It sounds as if it is coming from the back of the engine. Sort of sounds like very loose tappet but i have just checked all the clearances and they are fine. As its at cam speed, could it be the lift pump?

It also smoked very badly when i got it, but put some injector cleaner in and that seemed to reduce the black smoke remarkably but still gives out a load of blue on the over-run and down change, if i hit the throttle again. I am hoping this is valve stem seals and have ordered a headset to change these and give it a good decoke. i can also check out the condition of the bores whist the head is off.

Regards

Simon

Check crank shaft pulley bolt is tight

Thanks, will try that. It did however seem tight this morning when i was setting the tappets.

well checked that and it does seem f'in tight. Any other idea's?

Simon.

could the noise come from clutch area or is it definately forward of this

it really seems as though it forward of the clutch. Maybe lift pump area. It really does sound like noisey tappet until the throttle is pressed and it goes away. I also noticed when cleaning the intercooler that there was alot of oil in there and on the turbo and inlet pipe. Seems to be coming from the breather hose. What can cause this?

Well now that i have some oil in the rear diff things are a lot quieter when driving and the tapping noise does not entirly go away. There is still a tapping noise when driving under load, seeming to come from a similar or the same place. Could it be the lift pump? I gave a mate a lift earlier and he seemed to thing it was coming from the back end of the engine. Or could it be 2 seperate things sounding similar? Jamesmartin what was your thinking about the clutch?

It does seem that there was alot of oil in the intercooler and pipework, this coming from the breather. It does not seem to use much oil so maybe it just has not been cleaned out in a long time. However if it is caused by blowby could the tappety noise i can hear be something dire with the piston or rings?

Regards

Simon

simonmc73 said:

When i start the car, whether hot or cold there is a loud rattle, which dissapearers as soon as the throttle is touched. It sounds as if it is coming from the back of the engine.

Click to expand...

I get the same on both my 200 and 300....but it doesn't happen if I start the motor with the clutch pedal to the floor . . . . . I think both of us would be grateful for any advice.

I have just tried starting it with the clutch depessed a few times and the noise is not there, so that narrows it down some.

i have the same noise , but only when starting from cold .
i will try starting with the clutch depressed tomorrow , the noise goes away when you rev the engine ....

cheers mike

if it goes when idle raised or clutch pressed its usually clutch plate was a big problem years ago but some times arises with h/d clutches or poor springs in clutch plate

I think that would be the problem, as its not there if i start it with the clutch down. Looks like i may have my work cut out getting this one sorted! At least when i get the inner wings done all the metalwork will be sound for a while...

Simon