Fully opening injectors help the power

[ADow]

#1 son has been complaining that his 300D lacks power, particularly in comparison to his sister's. After making helpful comments like 'what do you expect, it's a 300D' I got him to sit in the car with the engine off and put his foot flat on the go pedal, and then I manually pushed on the injector linkages to see if there was any further travel - yes, about 2cm. Using the adjustment nut the slack was eliminated so that the injectors are now fully opened when he puts his foot flat down. It's made a big difference to the performance - not rocket science I know, but something to check if you want to get the best out of your diesel.

[AMG]

Perfect tip for a sticky topic.

[bruceT]

As long as you don't affect the kickdown rod when you do this. On my early 76 model it's a bit of a fiddle getting it right.

Alastair, have you done a diesel purge yet?

[ADow]

No purge yet - but I'm watching the discussion with interest.
Alastair

[bruceT]

There's not many diesels that won't benefit from a purge. Frees up the injectors and removes any carbon"cones" that form on them that cause them to squirt instead of spray. At around $20 per purge, it's a cheap service.

[Dweezil]

Did the purge recently on Hieronymous and noticed bugger-all difference. The thing that was obvious was the almost complete lack of smoke while doing the purge. Had to really hammer him to get a puff, but back to the usual "average" amount of smoke once the BD was back in.

Dweezil

[Tuppy]

Hmm i might try that one, my parents 300D is a lot faster then mine.

Then again theirs has a had a full engine rebuild and mine has done 480,000 without a rebuild so yeah that could be it too :lol:

[MB300D81]

Have you done valves adjustements for your diesel engine?

It is also amazing how much of a difference in performance the adjustments make.

[Gelandewagen]

Check the timing chain as well.

MercedesShopWiki: Measuring Timing Chain Stretch

[ADow]

I've had the injectors replaced. It's certainly quieter and seems to have more power.

[bruceT]

I've had the injectors replaced. It's certainly quieter and seems to have more power.

Hi Alastair

I'm interested to know what the old injectors looked like. Was there any "coning" or carbon build-up on the nozzles that can affect the spray pattern? Were they worn?

[ADow]

The ends of the injectors around the little spray hole were coated with a carbon buildup. The mechanic felt it was quite possible that the injectors were the originals. It was difficult to tell whether there was any wear to the needles without making a direct comparison with the old and the new, and I didn't see the injectors before they were installed. It only cost $90 labour to have them installed so I got a mechanic to do it. He was quite amused that we would be doing this with a 420,000 km car as injector replacement on w123 diesels is something he is rarely asked to do. The impression I got was that people are just running their diesels into the ground. If this is the case it is a shame because even at 420,000 km a well maintained 300D is a very good car - but then I don't need to tell you that!

[Screamin TE]

When i worked at a truck stealership, one of the things we used to do when customers complained of low power from their trucks, especially non turbo ones was a Wurth Hot Set, and a timing and valve clearance check.

Basically, you mix it with diesel to an amount that is relevant to the engine capacity, 500ml of product and 500ml of diesel per 3L of engine capacity.

Put the fuel pick up, and return line in the mix and run the engine on fast idle till the mixture runs out. Change filters, check and adjust timing, and check and adjust valve clearance.

We had truck coming in chuffing black smoke and really underpowered to leaving with completly clear emissions and going really well.

http://www.wurth.com.au/hotset.asp

[GrampiansMerc]

hey there I rang the company that makes Wurth Hot Set but they said it was not produced anymore.
Is there another product that would do the same job?

[Gelandewagen]

I won't vouch for this company, this stuff could be snake-oil as far as I know, but to answer your question:

http://www.costeffective.com.au

In my opinion there are no cheap-and-easy fixes for Diesel engines.

[petermc236]

I have used LIQUI MOLY Diesel purge with good results.
You can buy it from SuperCheap or can be bought online at http://www.liqui-moly.com.au/

Purge is also covered in this topic
viewtopic.php?f=5&t=7102

regards

[magenta]

The ends of the injectors around the little spray hole were coated with a carbon buildup. The mechanic felt it was quite possible that the injectors were the originals. It was difficult to tell whether there was any wear to the needles without making a direct comparison with the old and the new, and I didn't see the injectors before they were installed. It only cost $90 labour to have them installed so I got a mechanic to do it. He was quite amused that we would be doing this with a 420,000 km car as injector replacement on w123 diesels is something he is rarely asked to do. The impression I got was that people are just running their diesels into the ground. If this is the case it is a shame because even at 420,000 km a well maintained 300D is a very good car - but then I don't need to tell you that!

I'm interested to know who you are using as a mechanic in Adelaide? I need a good one for my 300TD

[julian]

Barrie Greene. Saw the introduction of the w123 as a mechanic and has been turning spanners on Mercedes since.
Excellent mechanic, great advice and very good prices.

http://www.derek.com.au/BARRIEGREEN.HTML

Others on here will confirm this.

[300TDT]

I'm about to replace the nozzles on my OM617.

Does anyone have any left-over shims that they don't need? Happy to pay.

[om diesel]

Hi everyone, injector nozzels on Om 636,621,615,616&617, generally do not have a lot of issues, other than water contamination. Faces (facing Pre-Chamber throat) will be eroded by combustion process. I am in ADELAIDE and can set up these nozzels. Contact, OLAF ZAWORSKI @ 83462650 or 0421515813

[mathuisella]

I'm about to replace the nozzles on my OM617.

Does anyone have any left-over shims that they don't need? Happy to pay.

you use the same shims that were existing in the injector to keep all of the pop pressures where they are supposed to be.

if you're talking about the crush washer that goes between the injector and the engine block when you install the injector, you get new ones from the stealership.