Hello everyone, long time no talk. Life has been busy and health has been bleh...

 

Long story short i was coming back from utah for a friends wedding and he was moving as well. I towed the uhaul trailer 6'x12' densly packed and very very heavy. Had no problems going through the mountains on HWY 80 EB till about 80 mi from lariamie WY. I was heading up a very long grade and towards the top something bad happened.

 

Here are the stats of when it happened

 

speed 70

gear 6

EGT under 1250 (no more than 60 seconds@1250, i saw it and turned the cruise off and throttled down)

boost around 20psi

rpm appx 1800~ cant remember exactly but was below 2000

oil psi normal ~65

fuel psi 18-20

temp rose from normal 180F to appx 200F when i powered down (within the white brackets)

 

What happened was a knock appeared and progressed to a loud knock quickly. I unloaded the engine and babied it to the crest which was less than half mile. Pulled over and the knock rose to a certain level and stayed there, excess blowby is observed and nothing else abnormal aside from the knock.

 

I havent torn into the engine but i am presuming either a cracked/melted piston or a conrod bearing went to hell or both.  I have my backup vehicle that ill be using for my trip and when i get back ill tear the engine apart.

 

Things i did learn from this, My RPM's were too low, egts were too high and in too high of a gear pushing too hard too long.

 

Fresh oil/filter air filter done before trip 3 weeks ago. zero issues aside from a cam sensor that gets fussy here and there. (was going to replace it when i got back this week as its bolt is stripped...)

 

Anyone have any thoughts or questions?

What kind of filter are you using

i honestly dont know how well this truck was taken care of before me, ive changed oil and filters around 6-10k miles, only towed twice (before the breakdown) and ive only put about 60,000 miles on since i bought it. im the second owner.

Make sure you are using fleetguard/baldwin/donaldson filters. Lesser filters are well know for breaking apart. There is a tsb of approved filters

I will take a look at my failure analysis book and let you know more about the main bearing tomorrow morning some time. The first two are the suspicious ones the rest of the main pics look about normal.

the pics i posted look like crap compared to the rest of the bearing which could be reused in an emergency (of which im not) just intruiging that some are trashed and some are perfect

fyi wild and free, the cooling nozzles on a couple had material in them i know #6 did, i had probably about less than 2000 miles on this oil change before failure

looks like because i had cruise control on going uphill it started lugging causing the bearing issue and egt went up cooking the piston...

http://www.agkits.com/bearing-failure-analysis.aspx

oh good news i do NOT have a 53 block!!! and i dont have to worry bout the KDP issue as the housing has a step inside to keep the pin in place

How much were you towing again when this happened? Sorry if this is a repeat question I don't recall. From what I have seen of these engines you would really have to have been doggin' it to trash the bearings, but anything is possible. I have always erred on the side of rpm's and dropped to 3rd (I have an auto) to get the horsepower up and egt's down. The engine seems alot happier at 2300+ rpm than down around 1600 or 1700 with a load.

What about the chunks you found in the oil filter? Those aren't from the mains are they? Are you going to have the machine shop check the alignment of the main journals while they have it?

ummm,  yah.   Man o Man..      You most  definitely need  to  have your rods  reconditioned.        From  what  I can see,  no  spinning of  bearing  took place,  but   those  dudes  took  a  pounding.  you were    'THIS CLOSE'   ><     TO   a  spun bearing!

My  shop  charges  about   40 bucks a rod  to cut and  hone  the  big end.  

 

Was  #6  cooling jet  plugged with crap?

How much were you towing again when this happened? Sorry if this is a repeat question I don't recall. From what I have seen of these engines you would really have to have been doggin' it to trash the bearings, but anything is possible. I have always erred on the side of rpm's and dropped to 3rd (I have an auto) to get the horsepower up and egt's down. The engine seems alot happier at 2300+ rpm than down around 1600 or 1700 with a load.

What about the chunks you found in the oil filter? Those aren't from the mains are they? Are you going to have the machine shop check the alignment of the main journals while they have it?

no sweat man, it was a uhaul 6'x12" dual axle trailer packed very very tight front to back side to side top to bottom. a family of 4 stuff. i was pulling up a long steep grade in cruise control and it was lugging the engine and over temped the pistons. it was my fault.the damage is enough to rebuild, they will check everything out at the shop.

ummm, yah. Man o Man.. You most definitely need to have your rods reconditioned. From what I can see, no spinning of bearing took place, but those dudes took a pounding. you were 'THIS CLOSE' >< TO a spun bearing!

My shop charges about 40 bucks a rod to cut and hone the big end.

Was #6 cooling jet plugged with crap?

number 6 and i think 4 was

and yeah i caught it just before it grenaded itself. i should have been using the right foot instead of the cruise... and downshifted

Edited September 23, 201410 yr by CUMMINSDIESELPWR

couple  questions here

 

Best of your  knowledge,   have you ever  had  antifreeze in your oil?

 

Were all  the  bearings   std.   Cummins?    If  not,  someone else  been in there...

 

upon  disassembly,   did you notice  any other  signs  of this engine  being apart before?    Usually,   RTV  in   odd places   is  a  giveaway...   wrench marks,  etc

 

Has this  truck  been  subjected to  extremely steep  operating  conditions..   ever been upside down?  (don't laugh)   I'm   sitting in one  right now!    ....  has  engine been  'killed/stalled'  before  you had a chance to  'clutch it'

Best of your  knowledge,   have you ever  had  antifreeze in your oil? NO

 

Were all  the  bearings   std.   Cummins?    If  not,  someone else  been in there...  YES

 

upon  disassembly,   did you notice  any other  signs  of this engine  being apart before?    Usually,   RTV  in   odd places   is  a  giveaway...   wrench marks,  etc  IT WAS A VIRGIN ENGINE

 

Has this  truck  been  subjected to  extremely steep  operating  conditions..   ever been upside down?  (don't laugh)   I'm   sitting in one  right now!    ....  has  engine been  'killed/stalled'  before  you had a chance to  'clutch it'  YES ON STEEP, WHEELING IN THE MOUNTAINS UP AND DOWN, YES MAYBE ONCE WHILE I OWNED IT ON STALLING.

 

caps not yelling lol

Ok,  last question!

you have any  'friends'  who  really hate your  Cummins?   ( you kick  the snot out of   a  ford or chev recently?)         

lol nah, i realized what i did and it was my fault. not paying attention and allowed the motor to lug in 6th going uphill with a load. first the bearings started making metal which plugged #6 cooler jet combined with high egt led to #6 piston almost melting.

 

lesson learned...   dont lug the engine, keep rpm's high egts low and lower speed while towing up grades

so after more parts cleaning i got to the oil cooler.

here is when it got weird.

i found wedged at the bottom of the input hole of the oil cooler a chunk of metal. pried it out and inspected.

it looks like a cast piece of aluminum that let go from something and i think it was in the oil filter feed side to where it got blown into the cooler...

i have no clue what it is or how it got in there

Looks like a thick washer. Cant remember if the main cap bolts have that thick or where that looks familure. Cam retainer bolt washer?

Anyways I wonder if that restriction didnt help with your issues.

Edited September 27, 201410 yr by mopartechnician

first...  see if it will stick to a magnet.  

I wonder where the other half  still is?    It may have  already gone out  with   previous oil change...  (did you save  the oil you drained out?)   time to  ' go fishin'

Appears  to   be  about   the  same  diameter as   a main bolt?

 

in any case,  it would've had to  made it past  the  pickup screen..      I'd  check your    pump internals,  and   the  pressure regulator  for  damage,  and for the  other  half of that  washer!   It may still be  under  a bolt head somewhere    ( or  galled into   something  you really  don't want to replace)..

Edited September 27, 201410 yr by rancherman

its not a washer, it came off a cast aluminum something and it was a half tab that a bolt held onto like a half hole cut onto a plate edge and a bolt held half of something and half of this...   but its not from the engine it is pot aluminum (cast) its very light and non ferrous

 

i do have the oil, and the stuff in the pan ill be filtering the oil soon.  this i think was already in the filter when i installed it, the pump is in top shape and no signs of foreign intrusion.  Taking everything apart i didnt see anything missing or half washers...  I think i got a junk filter with sh!t in it.

 

inspect your filters before installation and shake them out i guess no more purolator pure ones for me.