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Really appreciate that. Means a lot to me. When you go through the family court machine like I did, you look at things differently....It's hard to find people like you these days... and all those dedicated that come here and share their knowledge.
I'll add, here's a budget leak off setup I just finished. It just needs clear hoses. Will 1/4" be big enough to go over the OM642 injector or 5/16"?
Last edited by GoodByeHonda; Nov 25, 2019 at 09:20 PM.
My leak off results:
Few things to note for future reference. On my 2007 E320 with OM642, you want to use 1/4" clear tubing to run the test. If my math is correct and the limit references are correct, the limit should be at 79mm of diesel fuel filled from the neck of the injector return line in this 1/4" ID hose.
Removing plastic return line tops is accomplished easy with 14mm open-end flat wrench. Number 6 was difficult to pull off the injector. I used pliers and the plastic ring cracked. :/ I'll try to create another tool for that in the near future.
So, cranking the motor for 10 seconds and with crank sensor disconnected, I got:
Cylinder 1 - 0.0 mm of fuel
Cylinder 2 - 32.0 mm of fuel
Cylinder 3 - 3.0 mm of fuel
Cylinder 4 - 5.0 mm of fuel
Cylinder 5 - 5.0 mm of fuel
Cylinder 6 - 6.0 mm of fuel
For the second test, I reconnected the crank sensor and run the car cold for 3 min. (It started immediately LOL)
It looked like all injectors BUT No2 where the same. Number 2 cylinder injector returned DOUBLE the fuel compared to the rest of five injectors.
Looks like I need Injector No.2 replaced. It's a start....
Last edited by GoodByeHonda; Nov 26, 2019 at 05:09 PM.
My leak off results:
Few things to note for future reference. On my 2007 E320 with OM642, you want to use 1/4" clear tubing to run the test. If my math is correct and the limit references are correct, the limit should be at 79mm of diesel fuel filled from the neck of the injector return line in this 1/4" ID hose.
Removing plastic return line tops is accomplished easy with 14mm open-end flat wrench. Number 6 was difficult to pull off the injector. I used pliers and the plastic ring cracked. :/ I'll try to create another tool for that in the near future.
So, cranking the motor for 10 seconds and with crank sensor disconnectedI got:
Cylinder 1 - 0.0 mm of fuel
Cylinder 2 - 32.0 mm of fuel
Cylinder 3 - 3.0 mm of fuel
Cylinder 4 - 5.0 mm of fuel
Cylinder 5 - 5.0 mm of fuel
Cylinder 6 - 6.0 mm of fuel
For the second test, I reconnected the crank sensor and run the car cold for 3 min.
It looked like all injectors BUT No2 where the same. Number 2 cylinder injector returned DOUBLE the fuel compared to the rest of five injectors.
Looks like I need Injector No.2 replaced. It's a start....
Looks like you've found your issue. The max tolarance is 0.5" or 12-13mm. @32mm, you're well above the threshold.
BTW heres how you remove those return lines easily. Spray the rings with WD40 right before pulling each one. Then spin the ring in a circular fashion while your pulling up *with your fingers*.
And for the love of god, when you go to replace the injector drive the car 15-20 miles first. You want to do this with the engine HOT. If you do it cold, you risk breaking the hold down bolt in the head. You can reassmble with the engine cold.
Excellent. When recoding do not reset any adaptations. Just simply recode and drive. It may hiccup every now and then for a few weeks while the quantity adaptation is being recalibrated over 4 separate pressure levels.
Wow. The torque on the injector hold down claw is only 7 Nm +90 deg. (MB workshop recommends another 90 deg).
I'm of the opinion that if it isn't broken, don't fix it. But looking at my injector codes, I only had one changed so far. Would you guys recommend pulling them all and resealing with fresh copper washer?
Does any one know what the shear torque is on those T40 M6x1.0 injector claw hold down bolts?
Would like to attempt to take them out safely...
I believe OM642 shear torque on taking glow plugs out is 20 Nm. (Hot engine)
Thanks!
clamp force (7nm + 90 degrees) is about 15ftlb so its at least that. Remove them by hand, no power tools. Its going to sound like theyre breaking but their not. Not going to lie, its nerve racking. But the most important part is to do it hot after a thorough heat soak.
But bear in mind that after those 90 degrees turns, the bolt gets permanently stretched, so there is some margin error.
With my mechanical incline and years of experience, I have a sensor "build-into my hands" where I can sense when bolt is "giving" and avoid shearing it.
But assuming you have time to deal with it.- clean all the "black death" well and soak the bolt with PBlaster or equivalent for 2 or more days.
So with 1/4" inner diameter tube, a rise of fuel upto 13mm mark yields a volume of 0.412mL.
just want to make sure you're considering the same ID of tube as I used (1/4")
I went through MB workshop and could not find a reference value. I've been able to find a reference of 2.5 mL as a limit on sprinter forum. But I can't recall if this was for OM642 or OM648 injectors.
I believe its same for all bosch injectors. I recall reading from some WIS document 20ml/min (you can crank multiple staring sequences until minute is reached)
Thanks. Managed to pull the glow plug and the injector with such ease... have a peak at the glow plug and the injector tips. So dirty.
I should add that I tested this glow plug and it was under 1 Ohm. The one above is the new one I replaced. Looking at the one i pulled from the engine, seems like it had a lot of deposits. I pulled it just after running the car for 1 hour.
Coding the injector with Maxiecu is really easy. For some reason it saw the injector as #4 position not as #2. I was under impression that the 1st injector from the bumper on the drivers side was position #2. I guess mb software has it as #4.
Last edited by GoodByeHonda; Nov 30, 2019 at 11:13 PM.
Very happy to report that with -10 deg Celsius, car fired right up. Glow plug light stayed on for 4sec. Looks like injector is still calibrating itself as it hiccupsed for few seconds but for $50 cdn, it was a great deal. It came out of 2011 ML. Cheers!
Very happy to report that with -10 deg Celsius, car fired right up. Glow plug light stayed on for 4sec. Looks like injector is still calibrating itself as it hiccupsed for few seconds but for $50 cdn, it was a great deal. It came out of 2011 ML. Cheers!
Excellent news. It will hiccup occasionally for another 300-1000 miles until the quantity adjustment corrects itself.
BTW cylinders 1,2,3 are on the passenger side and 4,5,6 are on the drivers.
Almost all manufacturers count cylinder # on V engines between the sides and MB is probably only exception who counts numbers on passenger side starting on front and then switches the count on driver side.
Can get confusing.
Almost all manufacturers count cylinder # on V engines between the sides and MB is probably only exception who counts numbers on passenger side starting on front and then switches the count on driver side.
Can get confusing.
But bear in mind that after those 90 degrees turns, the bolt gets permanently stretched, so there is some margin error.
With my mechanical incline and years of experience, I have a sensor "build-into my hands" where I can sense when bolt is "giving" and avoid shearing it.
But assuming you have time to deal with it.- clean all the "black death" well and soak the bolt with PBlaster or equivalent for 2 or more days.
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