hypothetical #'s here, what do you think, is it bad?

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a guy with diesel on a diesel website I frequent posted his analysis #'s and asked if his motor is on it's last leg. I posted and redirected him here, you guys are smarter than me
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anyway, here's his #'s. What do you think? He didn't mention what kind of oil he runs. First sample, if I read it right, was taken after 5000 miles on oil, 2nd one at 12k miles same oil. 3rd sample was on new oil after 6k miles. Truck is 1991 CC dualley w/7.3,ats non wastegated turbo.

element, sample1 -- sample2 -- sample3

copper 3 -- xxx -- 37
iron 81 -- 309 -- 254
chromium 2 -- 10 -- 7
aluminum 8 -- 31 -- 30
lead 5
silicone 7
moly 89
sodium 2
Magnesium 33
tin 1
zinc 1410
potasium 1
phorosphorus 1190
calcium 3090
boron 51
silver 0
nickel 2
fuel dilution .6
soot .07%
water 0 sulfation 24 oxidation 12
antifreez 0
 
Aww thanks 1 FMF for the quick response & effort, Yupper it is my oil .The oil is Royal Purple(15-40 synthetic)taken on hot engine after 400 mile run.The engine has almost no sludge as it will start and run almost ****inuiously for week or longer not shutting down except to check oil or eat.Typical weeks are 4000 miles or so_Oil is changed at the shop on my way into town B4 i go home samples are taken then.So the oil is hot and very agitated.Yup you read it right.I guess my real question is how fast does this deterioation take place,how high are these #S are? the truck pulls a 30 ft goose neck weighing 12 to 24000 grosswhen loaded.Mostly high way.3-4 hrs idle time at night (idle set to 900 when sleeping:) ) fuel dilution was down to 0 last 2 reports .viscosity at 100 C was up from 14.3 to 17.3 to 15.4 on last sample.oxydation went from 12 at 5000 to 24 at 1200 to 26 at 6000 miles.Oil pressure good.
copper 3 -- 22 -- 37
iron 81 -- 309 -- 254
chromium 2 -- 10 -- 7
aluminum 8 -- 31 -- 30
lead 5 -- 16 --13
silicone 7 -- 25 -- 12
moly 89 -- 188 --206
sodium 2 -- 3 -- 3
Magnesium 33 -- 28 -- 24
tin 1 -- 2-- 3
zinc 1410 -- 1940 -- 1870
potasium 1 -- 6 -- 1
phorosphorus 1190 -- 1600 --1560
calcium 3090 -- 4870 -- 4810
boron 51 -- 18 -- 1
silver 0 -- 0 -- 0
nickel 2 -- 7 -- 7
fuel dilution .6 -- 0 --0
soot .07%
water 0--0--0
sulfation 24 --58 44
oxidation 12 --24--26
antifreez 0 -- 0--0
 
Oldmisterbill,

First of all I am not an oil analysis expert so touching on that aspect would be a guess on my part. But I want to make a couple of points on your truck if you don't mind so that everyone understands the ramifications of the wear numbers. When you load the gooseneck to 28K you are now grossley over your CGVW. Just guessing about 8K over. Also your engine was not turbocharged from the factory, so an aftermarket was added. These 2 factors would raise the wear on any vehicle under these conditions. Also you idle at 3-4 hours at 900 RPM, a value of 1200+ would be better in my opinion to prevent any wet stacking and wear from a cold engine. The IDI cools greatly when at idle.

Now these are only observations, not criticisms as I feel these things add to your wear. I think the oil is doing it's job, and you should be happy you got this kind of miles out of your engine.
 
Neil,

Wet stacking occurs in a diesel engine whent the engine is run at to light of a load. Unburned fuel will build up inside the engine. Also it will build up in the exhaust, and if it is long enough it can cause a tar like substance. It can cause enough deposits to keep one or more of the exhaust valves from closing properly and start to build up on the valve stems.

One way to prevent this is to use an AIC, automatic idle controller, set at 1200-1600 RPM. Plus turn on the air conditioner if it is summer for a partial load also.
 
because i know and understand how diesels work, i fail to see how it is possible to "wet stack" a diesel engine.
because they operate at such lean conditions when at idle i cannot see this as being possible.
i remember reading a bentley manual somwhere that stated a diesel idles around 100:1 air/fuel ratio.
diesel oil will evaporate in the atmosphere just sitting in a open container, so how would it be possible for it to stick up exhaust valves and such?

do you have any valid links to websites detailing this problem? somthing major like shell, dodge ford vw etc? i would not count "billys home page" as a vaid source.

edit: ok i did some research on my own and it appears wet stacking is possible primarely with large industrial engines and or cvery cold tempatures.
i stand corrected, by myself no less
pat.gif


[ March 26, 2003, 02:34 PM: Message edited by: cryptokid ]
 
quote:

Originally posted by cryptokid:
because i know and understand how diesels work, i fail to see how it is possible to "wet stack" a diesel engine.
because they operate at such lean conditions when at idle i cannot see this as being possible.
i remember reading a bentley manual somwhere that stated a diesel idles around 100:1 air/fuel ratio.
diesel oil will evaporate in the atmosphere just sitting in a open container, so how would it be possible for it to stick up exhaust valves and such?

do you have any valid links to websites detailing this problem? somthing major like shell, dodge ford vw etc? i would not count "billys home page" as a vaid source.

edit: ok i did some research on my own and it appears wet stacking is possible primarely with large industrial engines and or cvery cold tempatures.
i stand corrected, by myself no less
pat.gif


CryptoKid,

I "know" diesels as well, and even though you have already corrected yourself, I can tell you that wet-stacking can and does definitely happen (to people that don't know what their doing), but people blow it WAY out of proportion.

...Even in the coldest of conditions, all you have to do is bump up your idle a bit and any wet-stacking problem will disapear.

Heck, I use a stick cut-to-fit between the floorboard and the pedal. Cheap solution and works just fine.
 
CryptoKid,
Wet stacking does occur. You stated precisely the reasons. At low idle the very low fuelamount used lets the engine cool below its optimum operation point making for imcomplete combustion. I know you will ask for proof. Here is the story as I read it and the copy of the magazine, which was Progressive Farmer, is long forgotten, last year.
The article contained excerpts from both Cummin and Caterpillar. Here is the basic info.
Low idle should be avoided on ALL diesel engines except for 5 minutes before shutdown to let temps drop. If idleing more than 5 minutes shut the machine down or run at 1200 rpm or more approx. Both companies cited increased combustion area deposits and oil contamination by fuel as the primary reasons.
If you will notice also that long drain intervals are almost always given under strict circumstances, one of them is low or very limited idle time, now you know the whole story.
Hope this helps
GregH

[ May 15, 2003, 04:21 PM: Message edited by: GregH ]
 
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