Knackered 300TD Engine For Christmas

[Johner]

Inherited a 300TD Estate Elegance from my Dad 2 weeks ago and now the engine knocks and has black smoke from exhaust pipe, which has done 32,345 miles. The car has been looked after by Merc dealer, has all stamps in the service book, and has had regular oil changes in between the car is M.I.N.T.

The car drove 25 miles into work on an A road perfectly left for an hour or so and then started. On starting, it had a heavy engine knock so I switched it off straight away and checked under the car for oil and then checked the oil level no sign of leaks or the oil being low. Recovered to a local and very trusted garage where we started it left it to idle for 30seconds and listened to the knocking.

It sounds like big ends knocking and the black smoke from the exhaust is something quite awesome (as they say in the colonies) and no low level or oil pressure warning light on.

Just like to ask before the engine is stripped is there any thing else to look for apart from what sounds like engine damage.

Gut wrenching that a car, which has been looked after from day 1, just turns into a heap of junk in such a short time.

 

[jcev39]

That sounds more like you've got a hosing injector... I had something very similar on a Toyota Hi_lux where a bit of debris made the injector nozzle pickup ever so slightly preventing it from properly closing...

If the engine wasn't knocking before you turned it off its highly unlikely you'll have worn out the bearings with the engine off! Also injector would explain the black smoke. I would suggest pulling the injectors and getting the spray tested. You may need a new nozzle or two but thats somewhat cheaper than a complete rebuild...

Hope this helps

John

 

[Johner]

Thanks John

Much appreciated will look into your suggestion which sounds very reasonable.

John

 

[dieselman]

Deffo injector fault.
To find which one just run the engine at idle and crack the injector unions free one by one. When the noise and smoke stops you've found it.

You may also feel it through the injector pipe not pulsing properly.

 

[premmington]

Deffo injector fault.
To find which one just run the engine at idle and crack the injector unions free one by one. When the noise and smoke stops you've found it.

You may also feel it through the injector pipe not pulsing properly.

Yep....

I too would go with a duff injector...

Dripping...


http://www.remmington.plus.com

 

[FIBAMAN]

You could try the old screwdriver method. Place the tip of a suitably long screwdriver at the top of the injector and place the handle to your ear, you should be able to hear the regular rythm of the the injector lifting. A duff injector will sound different to the rest.

 

[Johner]

Thanks lads

Try these suggestions out in the new year. Certainly feel better now about the situation.

Merry Chrismas & Happy New Year

 

[dieselman]

Another check would be to run the engine at idle then raise the revs gradually to about 1500rpm. If the hammering noise gradually reduces then goes let the revs fall back to idle suddenly.
If the engine is quiet as the revs fall down to about 900rpm, then comes back on as the fuelling does, it has to be fuel related.

If this is the case go for the EGR valve being held open as a result of the MAF being worn out.
You can meter the MAF output to be sure before condemning it.

Honestly, this makes a noise like the engine is splitting in half.

 

[Johner]

Dear dieselman,

Thanks for your advice. Christmas gets better.

Thanks again and wish you a Merry Christmas and a Happy New Year to you and yours

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