Have you got a lumpy idle ?

[mathuisella]

Hey everyone, well my new car has a lump idle and the car shakes. Engine mounts look alright, and going off of this video i'm looking towards the fuel injectors.

part 1
https://www.youtube.com/watch?v=rAOVL3C0dvg

part 2
https://www.youtube.com/watch?v=7cdyiy4g930


So, i've taken the injectors out.

before, each injector
https://www.youtube.com/watch?v=CCbY1yS76p4
https://www.youtube.com/watch?v=DbP-COShXnk
https://www.youtube.com/watch?v=0pTbfBMUuz8
https://www.youtube.com/watch?v=8psQFTET9us
https://www.youtube.com/watch?v=W6fz49BVSZ0


and how they should be, ( using a video from my red om617 NA, post cleaning )

cleaned with old nozzle
https://www.youtube.com/watch?v=a0Fbeg-X6A8

cleaned with new nozzle
https://www.youtube.com/watch?v=RzE7D4bCnZM


and how the injectors are currently

37325955_10214512907389236_4643418963387088896_n.jpg

37265766_10214512906389211_8251406184557314048_n.jpg

37250887_10214512908029252_7974884937226518528_n(1).jpg

some of them were so stuck they needed persuading..

37346182_10214520250332805_7723209697745960960_n.jpg

37372201_10214520248812767_9141022825002303488_n.jpg

and putting them in the ultrasonic cleaner after a brass brush cleaning by hand.

[mathuisella]

37272275_10214520249212777_3303762412578013184_n.jpg

37284629_10214519601916595_1212987519889571840_n.jpg

[Bartman4800]

The top picture looks like some eejit put loctite thread locker on the thread of the injector?
That is a big no no...
Or could it be the remains of vegetable oil?

What fluid did you use in your Ultrasonic Cleaner?


Bart

[mathuisella]

It's the remains of heavy vege oil use.

I use mineral turps, reccomended by a friend who's has a ultrasonic cleaner a lot longer than me.

the nice and clean injector body is the combination of a brass brush as well as the ultrasonic cleaner, either of them by themselves won't get that sort of result.

Currently cleaning injector nozzles, i've got a pretty good idea why lumpy idle, the nozzles were so stuck that when the car heated up, metal expanded and the carbon deposits around the nozzle ect: acted like a gasket and made a tough seal that the car couldn't get through with enough pressure unless the car was off of idle. My random thought on it any ways.

P.S does anyone have the tool to remove the collar and the prechamber ? i would love to give those a clean as well :(

[Bartman4800]

I don't have the tool, unfortunately.

But have you tried vinegar to dissolve this gunk?
It worked great on carburetors.. and it is dirt cheap


Bart

[mathuisella]

Yeah, dissolving it would be nice, but it would all go as a liquid into the cylinders :/

I'm wanting to take the prechambers out and put them into my ultrasonic cleaner :)

[tsharkey]

Hi ya, I have the tool but may be a bit far away.

Can you post some details of the ultrasonic cleaner ?

btw - Did you ever get those 2 way check valves ?

[mathuisella]

Those check valves came through. How much do i owe your for them ?

Oh and sadly it wasnt the valve, i still have a leak narrowing it down to the fuel door or boot.

An overnight satchel to brisbane would be amazing.... just let me know your bank details, more than happy to pay postage costs to get the prechambrr and the collar out so i can clean them.

The ultrasonic is a 3 litre one from ebay. $105.00 with 2 ultrasonic generators in it as well as a heater. Like this one

https://m.ebay.com.au/itm/Digital-Ultra ... ultra.TRS0

[mathuisella]

I bought this, shipped from the USA.

https://www.ebay.com.au/itm/Mercedes-4M ... 2749.l2649

Cost $150 :(

Am i correct in thinking that i need a seperate puller for the prechamber itself ?

[tsharkey]

Hi - Meant to reply and say yes you can borrow, sorry. There is a puller that screws in and uses a slide hammer to remove or bolt to unscrew to pull out - You could fashion one your self

http://www.peachparts.com/shopforum/die ... uller.html

Tim/

[mathuisella]

Hi - Meant to reply and say yes you can borrow, sorry. There is a puller that screws in and uses a slide hammer to remove or bolt to unscrew to pull out - You could fashion one your self

http://www.peachparts.com/shopforum/die ... uller.html

Tim/

looks like with the tool i bought, i may be okay for the collar, but for the prechamber, i'm finding it difficult to find the 22mm bolt/threaded rod with 1mm thread pitch needed.

called machine shops, cost $100 for a 100mm length of M22 with 1mm thread pitch

saw a couple of pieces online, cost me another $150 aud :'(

Should've just bought the one from mercedes source, as it screws into the prechamber to remove the collar and then can be combined with a slide hammer.

Just going to shell out the $150 and get the mercedes source tool, just to be done with it and throw it in the tool box for 10 years until next use.

https://www.youtube.com/watch?v=8uTuk1RZRjk

[tsharkey]

called machine shops, cost $100 for a 100mm length of M22 with 1mm thread pitch

Aren't the DIY'ers using an old bike crank to get the thread you are after ?

[mathuisella]

called machine shops, cost $100 for a 100mm length of M22 with 1mm thread pitch

Aren't the DIY'ers using an old bike crank to get the thread you are after ?

I don't have any bicycles :'( there is however a discarded bike a few streets away from me. too bad i just ordered the part from mercedes source. Ah well. It's done now and any other brissie people in the future could borrow the tools off of me.

[mathuisella]

https://youtu.be/nWrJDjCFm9U



after all the following, the engine has lost 99% of it's rough idle, yet to confirm 100% as i'd need to take it for a drive :P


1. fuel injector delivery valves.
2. fuel injectors nozzles.
3. engine mounts.
4. valve adjustment.
5. rocker arm correction.

Just thought to update this specific thread as per the topic of it was directly for the lump idle.

So if you have a lumpy idle, check the list of things as above and if anything is unclear, i'm happy to take pictures and video to help explain :)

[mathuisella]

Still have lumpy idle. unsure where to go from here :/

[tsharkey]

Have you tried IP Rack Damper Adjustment ?

https://mercedessource.com/problems/eng ... adjustment

Is the rough idle only when cold, or only when warm or always ?

[mathuisella]

Have you tried IP Rack Damper Adjustment ?

https://mercedessource.com/problems/eng ... adjustment

Is the rough idle only when cold, or only when warm or always ?

I had a crack at it, i think it's been 'adjusted' all the way in. I didn't notice any difference.

the lumps idle seems to be there all the time. It's a lot better than before when i first got the car as the engine mounts, injectors, fuel and air filters have all been changed.