Sorry about late response but mine is the non turbo 617.912 engine -no oil spray jets to cool pistons. I seemto recall that the oil pump thrust "bearing" that screws in at the top was quite worn when I overhauled the engine and was replaced with a new one. This thrust piece has a copper face that wears -perhaps this is the source of the copper? I think I will have to remove the current it and see if its worn
On 28/10/2008, Loren Faeth <[EMAIL PROTECTED]> wrote: > > Yes, and if the tops are not kept cool, oil can burn on the rings and in > the grooves. This will create a problem similar to what Peter described. > As always, it is just something to check, and not a diagnosis > > At 05:37 PM 10/27/2008, you wrote: > >> The oil spray nozzles are used for cooling the piston tops. >> >> Thanks, >> Tom Hargrave >> www.kegkits.com >> 256-656-1924 >> >> >> -----Original Message----- >> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] >> ] >> On Behalf Of Loren Faeth >> Sent: Monday, October 27, 2008 5:05 PM >> To: Mercedes Discussion List >> Subject: Re: [MBZ] Oil analysis problem >> >> Is it possible the piston oil spray nozzles were not cleaned and >> working during the previous rebuild? That might account for the >> rings being carboned up the first time, and again now. >> >> At 04:40 PM 10/27/2008, you wrote: >> >Hi Peter -- >> >You asked <<what actually lubricates the bores? is it splash/leaks >> >from the small end?>> >> > >> >IIRC you wrote that a 300 W123 was the problem (in your fleet ;-) >> >and I believe - not 100% sure - the 300D Turbo had squirters under >> >the pistons and the non turbo did not - I believe those squirters >> >cool the piston crowns and provide some lubrication to the cylinders >> >- otherwise it comes from splashing of the crank. >> > >> >The carbon on the rings certainly sound like a strong >> >likelyhood. What kind of driving does this car see? Any long >> >distance/high speed stuff? >> > >> >I do not believe it has anything to do with your rebuilding >> >technique. I suspect you are right about the machine shop not >> >having enough crosshatch to get good ring bedding. >> > >> >It's also extremely important to have a shop that is xperienced with >> >MB - hopeflly yours was. When I rebuilt my 240D I replaced the >> >sleeves and pistons/rings - I had to replace the pistons because >> >several rings had broken and damaged the piston grooves/lands. >> > >> >But when honing for new rings it's not all that difficult to do - >> > >> >Let me ponder this some -but those carboned rings really sound like >> >the problem - but I wonder what caused it the 1st time? Any idea? >> > >> >Later -- >> > >> >Sincerely, >> >Larry T (74 911, 91 300D 2.5T) >> >www.youroil.net Oil Analysis Kits & >> >Porsche Posters/Weber parts >> >----- Original Message ----- From: "Peter Merle" <[EMAIL PROTECTED]> >> >To: "Mercedes Discussion List" <mercedes@okiebenz.com> >> >Sent: Monday, October 27, 2008 1:57 PM >> >Subject: Re: [MBZ] Oil analysis problem >> > >> > >> >>Larry , compression is down - around 18 bar all round and starting has >> >>become more slightly more difficult. It did not achieve full 24 bar when >> >>newly overhauled and I can only ascribe this to not optimal machining. >> >>honing by engineering shop - perhaps this is the cause of the malay?? >> Oil >> >>pressure is 2 bar at idle hot and it pegs at 3 immediately. Was >> thinking >> - >> >>what actually lubricates the bores? is it splash/leaks from the small >> end? >> >>What is also unusual is that when I overhauled the engine all the rings >> >>where carboned up onto the piston on all 5 pistons. I suspect the same >> might >> >>be happening again. I was not however my driveing that contributed to >> this >> >>as I had just bought the car when I overahuauled it. My other Om617's >> show >> >>now sighn of similar problems - I also overhauled my 300GD ( a crack in >> head >> >>that had been repaired by previous owner was starting to leak ) and >> thats >> >>going well. Oil consumption is still low ( arround 0.2 l/ 1000 km ) >> >>PEter >> >> >> >> >> >> >> >>2008/10/27 LarryT <[EMAIL PROTECTED]> >> >> >> >>>is the oil consumption from leaks or is it being burned? >> >>> >> >>>If burning, the time it is burning will help understand what might be >> >>>wrong. If after idling for a few minutes you accelerate and leave a >> smoke >> >>>trail bad valve guides are indicated. If it has white oil smoke >> >>>whiledriving at a steady speed, rings are likely the problem - or >> something >> >>>related to the pistons. >> >>> >> >>>A single oil sample is not as informative as several - preferably at >> >>>intervals of 1500 miles or more. >> >>> >> >>>As Curt pointed out, results are best evaluated over time. The history >> of >> >>>the engine is helpful info also - if used for short trips where it was >> not >> >>>warmed enough to burn off carbon deposits a misleading indication can >> ccur >> >>> -- >> >>> >> >>>Sincerely, >> >>>Larry T (74 911, 91 300D 2.5T) >> >>>www.youroil.net Oil Analysis Kits & >> >>>Porsche Posters/Weber parts >> >>>----- Original Message ----- From: "Peter Merle" < >> [EMAIL PROTECTED]> >> >>>To: "Mercedes Discussion List" <mercedes@okiebenz.com> >> >>>Sent: Sunday, October 26, 2008 4:04 AM >> >>>Subject: [MBZ] Oil analysis problem >> >>> >> >>> >> >>> Sent oil samples from my 5 300D 's to the lab ( 3 x W123's , 1x 300GD >> ( >> >>>>OM617 ) and 1xW124 ) and got satisfatcory results from 3 off them . >> The >> >>>>one >> >>>>W123 ( the only one running Mobil 1 ) had high levels of Copper and >> Iron >> ( >> >>>>29 and 71 ppm ) after 2000 km. Sodium, Siicon, Al , Cr , particulates, >> >>>>soot >> >>>>are all low . Lab suggested the oil pump is worn and I should test oil >> >>>>pressure . Well the oil pump had done only 60000 km and oil pressures >> are >> >>>>good. The engine is loosing compression and oil consumption has >> increaseed >> >>>>since engine rebuild a few years ago so something is not right. Any >> >>>>ideas >> >>>>anyone? >> >>>> >> >>>>Am going to change oil to delo 400 and then see what the results are. >> >>>> >> >>>>Regarding the other car with poor results - I had just bought it - has >> >>>>been >> >>>>running on WVO for 30000 km - well its oil had high levels of iron ( >> 93 >> >>>>ppm >> >>>>) as well as particlates - diagonis by lab was that oil filter was >> being >> >>>>bypassed ie filter blocked. is this a problem with WVO ? Does the >> stuff >> >>>>get >> >>>>into the engine oil and block the filter? >> >>>> >> >>>>Peter >> >>>>_______________________________________ >> >>>>http://www.okiebenz.com >> >>>>For new parts see official list sponsor: http://www.buymbparts.com/ >> >>>>For used parts email [EMAIL PROTECTED] >> >>>> >> >>>>To Unsubscribe or change delivery options go to: >> >>>>http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com >> >>> >> >>> >> >>>_______________________________________ >> >>>http://www.okiebenz.com >> >>>For new parts see official list sponsor: http://www.buymbparts.com/ >> >>>For used parts email [EMAIL PROTECTED] >> >>> >> >>>To Unsubscribe or change delivery options go to: >> >>>http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com >> >>_______________________________________ >> >>http://www.okiebenz.com >> >>For new parts see official list sponsor: http://www.buymbparts.com/ >> >>For used parts email [EMAIL PROTECTED] >> >> >> >>To Unsubscribe or change delivery options go to: >> >>http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com >> > >> > >> >_______________________________________ >> >http://www.okiebenz.com >> >For new parts see official list sponsor: http://www.buymbparts.com/ >> >For used parts email [EMAIL PROTECTED] >> > >> >To Unsubscribe or change delivery options go to: >> >http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com >> >> Loren Faeth >> >> >> _______________________________________ >> http://www.okiebenz.com >> For new parts see official list sponsor: http://www.buymbparts.com/ >> For used parts email [EMAIL PROTECTED] >> >> To Unsubscribe or change delivery options go to: >> http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com >> >> No virus found in this incoming message. >> Checked by AVG. >> Version: 7.5.549 / Virus Database: 270.8.3/1748 - Release Date: 10/26/2008 >> 7:53 PM >> >> >> No virus found in this outgoing message. >> Checked by AVG. >> Version: 7.5.549 / Virus Database: 270.8.3/1748 - Release Date: 10/26/2008 >> 7:53 PM >> >> >> >> _______________________________________ >> http://www.okiebenz.com >> For new parts see official list sponsor: http://www.buymbparts.com/ >> For used parts email [EMAIL PROTECTED] >> >> To Unsubscribe or change delivery options go to: >> http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com >> > > Loren Faeth > > _______________________________________ > http://www.okiebenz.com > For new parts see official list sponsor: http://www.buymbparts.com/ > For used parts email [EMAIL PROTECTED] > > To Unsubscribe or change delivery options go to: > http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com > _______________________________________ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
