e250td 98' diesel ignition how to check

[poisas]

Hi, here I'm again, I have started to suspect that my merc ignition is alittle to late or retarded, is there any suitable way to check it ?
how it is ajusted, cause the fuel pump is mechanical with electronic back, thats how they call it here.

Thanks.

 

[Number_Cruncher]

How worn is your timing chain?

Unless the injector pump has been disturbed, wear of the chain and sprockets is the only way that the timing can have become retarded.

Why do you think the timing is retarded?

 

[poisas]

This not about why, but about How to check it I'm not 100% sure, but i beleave its very little retarded, and I would like to have very little advanced.
Car is about 200k on clock.
So any way what i need to know how to check, or how to adjust the timing, i know this is very difficult to do, but i need to know if its possible to ajust via ECU ?

How worn is your timing chain?

Unless the injector pump has been disturbed, wear of the chain and sprockets is the only way that the timing can have become retarded.

Why do you think the timing is retarded?

 

[Number_Cruncher]

>>if its possible to ajust via ECU

No, you can't adjust electronically.

The pump is driven by the chain and timing is entirely mechanical - hence my questions.

 

[poisas]

OK , i was at service, and asked to advance igintion aproximaly by 5degree, they told me we have turned 3rounds with adjusting screw, this should be about 5degree. I have notice such an improvements, engine is running more smooth 650-2000rpm , before it was shaking a litle.
Starting Hot engine is good as cold, before hot engine was need to have extra 1s to start. Slightly improved power at low rpm, but still i cannot comparre to my fathers audi 2.5tdi, i suppose thats direct injection thing, his is picking rpm much much faster in neutral. For me it takes a while to go from 650rpm to 1500 , in futher range, both car is more enough equal.
But this range 650 to 1500 is real pain in this car is it because non directional diesel injection ?

 

[lynall]

That screw is probably the max fuel screw and nothing to do with the timing.

Timing is probably adjustable on the sprocket, used to be a common mod on auto tdi discoveries to overcome cold start problems, loosen screws advance pump, you know when you have gone to far as engine light comes on, back it off very slightly and there you have it an instant starting discovery

Just looked at russian site and didnt realise its an inline pump, so yours is probably different, discovery was rotary pump.



Lynall

 

[poisas]

That screw is probably the max fuel screw and nothing to do with the timing.

Timing is probably adjustable on the sprocket, used to be a common mod on auto tdi discoveries to overcome cold start problems, loosen screws advance pump, you know when you have gone to far as engine light comes on, back it off very slightly and there you have it an instant starting discovery

Just looked at russian site and didnt realise its an inline pump, so yours is probably different, discovery was rotary pump.



Lynall

Nop, that screw is spec for adjusting timing, there is no such screw for adjust fuel on my pump, i would like to have that
also, 5degree is alot in adjusting ? what is the interval in diesel for ignition adjusting in degree ? :

 

[R Phillips]

How can you agust the advance on the ignition?
I thought Diesel's were compression ignition, ie the fuel burns as it gets so hot being compressed.

 

[R Phillips]

How can you adjust the advance on the ignition?
I thought Diesel's were compression ignition, ie the fuel burns as it gets so hot being compressed.
There is no spark to time?

 

[poisas]

How can you adjust the advance on the ignition?
I thought Diesel's were compression ignition, ie the fuel burns as it gets so hot being compressed.
There is no spark to time?

Ignition in diesel is managed by seting on the same chain Main cam, valve camshaft, and fuel pump. They are adjusted to very very exactly to be in perfect timing. Pump is atached so thanx to smart mercedes engeneering, so you can twist pump, and that way you are changing timing in old non direction ignition diesels. Mercedes had implemented spec screw for adjustment. cause its so sensitive, so you can use that screw to make 1degree steps. Imagine your clock, if you twist 1minute, it would be 6degree already! in TDI, and comonrail, the ignition can be adjustes via ecu, because pump is electronicaly controled. Comon rail i heard it never needs to adjust ignition. But old non direct diesels mercedes, they are chain driven, so as time passes chain is worn, and this makes ignition to become alitle retarded. this was my idea when i did advancing.