E7 engine ruined after 9hrs rebuild - trying to understand why

[Okiki Olufokunbi]

Hello folks,

I do need some assistance and help in trying to understand why an E7 PLN engine failed hours after the rebuild. The truck operates out of Africa.  I have attached some pics  and will attach more as I get them.

The engine had to be rebuilt after it threw a rod, poked a hole in the sleeve and  broke the cylinder block. This happened because the connecting rod  bolt came loose and the rod came off the crankshaft journal. So the rebuilt involved a new block, and a new crankshaft amongst other things. The truck had an inframe sleeve replacement a year prior, and the pistonless PAI kit was used during the replacement. The PAI Main and rod bearings that came with that sleeve replacement job were not used back then, but was used with this rebuilt. Apparently these PAI rod bearing were coated bearings

After this  rebuild, with the installed PAI main and rob bearings, the engine was started up and then left running at idea about 3 hrs. It was then shutdown for about 8 hrs, and restarted again. 2 hours into the second run (at idle), the engine shut itself down and would not restart. After letting the engine cool down, the engine was started up again, but it began to give a knocking sound. It was quickly shutdown, and the oil was drained and the oil pan drop.

The aftermath was ugly my friends. The number 2 cylinder rod bearing had overheated, spun around and extruded. The rod bearing oil hole was virtually plugged off with metal shavings and coating material. The other 5 rod bearing were all scarred up, and already have shavings. Their oil holes were still open, but had already started being plugged with shaving materials.  But they did not look like they had spun. The new crankshaft was again shot.  It was quite obvious that to me and all so far that the journals seemed to have lost lubrication, but  number 2 likely went all the way dry and stopped receiving oil completely. I am trying to understand why, so as to really get to the root cause of the failure.

 

How does oil get to the individual rod bearings? Unfortunately I don't have my E7 manual with me, but I was under the impression that each of the main bearing got supplied oil from dedicated Engine block oil gallery , and then the main bearing would supply the rod bearings through the oil paths in the crankshaft. Is this incorrect? One of the Tech was contending that the oil flowed down from one journal end of the crankshaft to the other  but is he correct?

This was the first time the Techs  have ever used coated bearings in any of their rebuilds, to their argument is that the coated PAI connecting  rod bearings  were not good, and definitely wrong for the application. The Tech are of course skeptical, and contend that the rod bearing started shaving off  as soon as the engine was started, and finally the number two shaved off to the point of plugging off the oil hole, stopping oil flow, then overheated. Has anyone here experienced a failure as a result of using coated rob bearings or PAI rod bearings in particular?

Please let me know if you have any more questions or need more information to diagnose. I have my opinions at to what happened, but wanted to get your inputs first. Thank you for you time

OO

 

[Mack Technician]

Sorry to see it man. PAI is fine quality, one of the owners of PAI have rights to all MACK brand intellectual property. Forget about bearing coating being a factor...it's a non-issue. Only reason that coating wasn't working is because no oil was touching it. Gotta figure out how you lost oil pressure and did not realize it. If you did not lose oil pressure need to figure out how you got over size rod bearings on a standard size crank. They look std size?  I'll get you some info ASAP.

[Mack Technician]

Don't have PLN break down. This is E-tech. It does stand to show that (it is assumed) all oil that goes into crank mains is shared to rod bearings via drilling. They don't even show the crank since it is part of main circuit.

Africa.pdf

[TeamsterGrrrl]

Makes one wonder if a bad oil pump or something else blocking the oil circuit or leaking off oil pressure caused both this and the previous failures?

[Mack Technician]

Get your parts receipt and run the numbers on brg/engine kit. Too tight or loose on oil clearances and it may have like affects. Loose generally make an inspection hole in block. Mis-cut and never plastigauged??? Don't know what kind of stuff goes on at an African machining shop?

We just sent a truck down to Nigeria last summer. PLN, early 1998, Blue, Wet-kit, 427 horse, got hit and totaled on left drivers side......Shipped out of Manders Diesel Minnesota.

[Freightrain]

Is it common practice to just let a new diesel engine idle for 3 hrs for break in?   

Was there an oil pressure gauge?  Wonder if the pump relief stuck open and was not pumping enough.

[fjh]

Was the oil pedestal removed there's several different gaskets for diffrent applications?was the oil cooler cleaned properly from the first engine failure?

Edited June 7, 2017 by fjh

[Okiki Olufokunbi]

4 hours ago, Mack Technician said:

Sorry to see it man. PAI is fine quality, one of the owners of PAI have rights to all MACK brand intellectual property. Forget about bearing coating being a factor...it's a non-issue. Only reason that coating wasn't working is because no oil was touching it. Gotta figure out how you lost oil pressure and did not realize it. If you did not lose oil pressure need to figure out how you got over size rod bearings on a standard size crank. They look std size?  I'll get you some info ASAP.

Thanks for the response so far . Is the PAI- 8332-P1 an oversized rod bearing? I did order a standard kit from the PAI dealer back then, and the Techs that measured the replacement crank (now damaged) assured us that the replacement was a standard sized crank .

 

OO

[Okiki Olufokunbi]

The oil pressure was at 60 psig on idle (2nd startup- prior to failure) , but no one recalls what it was when the engine shut itself down.

[Phase 1]

"This happened because the connecting rod  bolt came loose and the rod came off the crankshaft journal."

I have no experience with this engine but finding a complete rod bolt when there is a thrown rod may not mean that the cause was a loose bolt. I have seen it before and I believe (and others have agreed) that when a rod starts hammering due to a bearing going bad, the pounding can cause a bolt to loosen. If that is what happened, it is possible that the problem you have now also caused the previous failure.

[AZB755V8]

On 6/7/2017 at 6:43 PM, Okiki Olufokunbi said:

The oil pressure was at 60 psig on idle (2nd startup- prior to failure) , but no one recalls what it was when the engine shut itself down.

The end result of the failure is oil starvation to the rod bearings. If the bearings were .010 over I don't thing the engine would have turned over in the first place. I think the real issue is the main bearings. This rebuild would not be the first time main bearings were installed wrong. I have seen bearings with the oil groove in only one shell, it maybe the case with an E7 engine. That shell must be installed in the block and the ungrooved shell in the main cap. The engine will have oil pressure but no real amount of oil to the rods if the grooved shell is in the main cap. 

[Hobert62]

This is what happened to my dads reman cummins the other year.  It was still at the cummins shop on there dyno for break in.  (so no warranty issue".     I think they determined it was due to rod bearing put in backwards.   He had 2 new motors on a weeks time.  

[Underdog]

Don't know if it still applies to modern E7's, but several Mack techs told me #2 rod bearing is always first to fail, because it is the last to receive oil as it is pumped through the engine. This after I spun #2 rod bearing in my 673P.

[Mack Technician]

Second illustration attached.

2 tab location.pdf

[Okiki Olufokunbi]

1 hour ago, Mack Technician said:

Second illustration attached.

2 tab location.pdf

here is a pic of the crankshaft. I see some scorring on the main bearing journal next to the failed rod bearing journal. The comment about thrust bearing installation ( in the 1 tab location.pdf)   is interesting. I expect to receive pics of the main bearings this weekend.

Another question that is arising is why the other rod bearings started wearing down too, and pieces started shaving off them.

[Okiki Olufokunbi]

10 hours ago, Phase 1 said:

"This happened because the connecting rod  bolt came loose and the rod came off the crankshaft journal."

I have no experience with this engine but finding a complete rod bolt when there is a thrown rod may not mean that the cause was a loose bolt. I have seen it before and I believe (and others have agreed) that when a rod starts hammering due to a bearing going bad, the pounding can cause a bolt to loosen. If that is what happened, it is possible that the problem you have now also caused the previous failure.

With the thrown rod event, I got that feedback from the driver about an unusual sound, but they did not address this in time.  it was the number 5 that threw the rod, I will try to get the details correct, but there was a missing bolt of the connecting rod, and the other was bent.

[Mack Technician]

Looks to me like you just, plain, lost oil.... everything got hit.

[Okiki Olufokunbi]

44 minutes ago, Mack Technician said:

Looks to me like you just, plain, lost oil.... everything got hit.

Thanks for all your assistance. I am still in not sure why the oil got lost. The engine is being rebuilt again, with non PAI bearing parts this time. Is there a way to check for oil supply to all the journal points with the motor not running? Another failure will be devastating . 

Edited June 9, 2017 by Okiki Olufokunbi
content correction

[Mack Technician]

You sound like an involved owner (and/or) operator. I hate to sound critical and I don't know how they do it in Africa, but up here.......if I rebuild your engine it better damn well last through the warranty period or I'm buying you a new motor. The shop supervisor is devastated, not the customer. It is the mechanics liability to oversee the complete engine repair, confirm all tolerances  and flag all components that have potential for a premature failure or have stepped outside service specs. I say fire the crew and "start again Finnegan".    

[TDBach]

On 6/7/2017 at 9:12 AM, Okiki Olufokunbi said:

Hello folks,

I do need some assistance and help in trying to understand why an E7 PLN engine failed hours after the rebuild. The truck operates out of Africa.  I have attached some pics  and will attach more as I get them.

The engine had to be rebuilt after it threw a rod, poked a hole in the sleeve and  broke the cylinder block. This happened because the connecting rod  bolt came loose and the rod came off the crankshaft journal. So the rebuilt involved a new block, and a new crankshaft amongst other things. The truck had an inframe sleeve replacement a year prior, and the pistonless PAI kit was used during the replacement. The PAI Main and rod bearings that came with that sleeve replacement job were not used back then, but was used with this rebuilt. Apparently these PAI rod bearing were coated bearings

After this  rebuild, with the installed PAI main and rob bearings, the engine was started up and then left running at idea about 3 hrs. It was then shutdown for about 8 hrs, and restarted again. 2 hours into the second run (at idle), the engine shut itself down and would not restart. After letting the engine cool down, the engine was started up again, but it began to give a knocking sound. It was quickly shutdown, and the oil was drained and the oil pan drop.

The aftermath was ugly my friends. The number 2 cylinder rod bearing had overheated, spun around and extruded. The rod bearing oil hole was virtually plugged off with metal shavings and coating material. The other 5 rod bearing were all scarred up, and already have shavings. Their oil holes were still open, but had already started being plugged with shaving materials.  But they did not look like they had spun. The new crankshaft was again shot.  It was quite obvious that to me and all so far that the journals seemed to have lost lubrication, but  number 2 likely went all the way dry and stopped receiving oil completely. I am trying to understand why, so as to really get to the root cause of the failure.

 

How does oil get to the individual rod bearings? Unfortunately I don't have my E7 manual with me, but I was under the impression that each of the main bearing got supplied oil from dedicated Engine block oil gallery , and then the main bearing would supply the rod bearings through the oil paths in the crankshaft. Is this incorrect? One of the Tech was contending that the oil flowed down from one journal end of the crankshaft to the other  but is he correct?

This was the first time the Techs  have ever used coated bearings in any of their rebuilds, to their argument is that the coated PAI connecting  rod bearings  were not good, and definitely wrong for the application. The Tech are of course skeptical, and contend that the rod bearing started shaving off  as soon as the engine was started, and finally the number two shaved off to the point of plugging off the oil hole, stopping oil flow, then overheated. Has anyone here experienced a failure as a result of using coated rob bearings or PAI rod bearings in particular?

Please let me know if you have any more questions or need more information to diagnose. I have my opinions at to what happened, but wanted to get your inputs first. Thank you for you time

OO

 

Oil pump failure? Take the oil pump apart and check the relief and regulator valves... Oil gets in through the crank shaft through the main bearings...hmm...clean cure failure.. assembly debris lodged into the bearing... machining material from new block...? 

Ms Tracy D 

[macks in nigeria]

I feel your pain.Get yourself a very good used engine from the US and ship down for your truck.For some reason rebuilt engines don't really work in Nigeria hence the huge demand for used engines here.Good luck with whichever route you choose.

[Lmackattack]

If all of your bearings have these issues after just a few hours run time I would say you are looking at a oil pump or oil flow issue.

where is the oil gauge plumbed into? if its close to the pump it will tell you it has good pressure but it cant tell you if other components are seeing that pressure further into the oil system.

If the pump is giving you good pressure than it must be sending the oil to a major internal leak. fluid flows to the path of least resistance. if you have a major leak inside the engine the pump will push 90% of the oil to that exit path and other components will starve. for example if this engine calls for piston oil coolers but they were not installed, major oil flow will come thru this passage unrestricted where other oil passages will see a trickle of flow with little to no pressure behind it. oil flow thru a crank needs solid pressure as it needs to feed other bearings. If your rods and mains have failed but the cam bearings are ok than start looking for a blockage or internal leak in the block.

most engines running at idle can safely run very low pressure so long that all components are getting pressure. some may recall the old Detroits that would only have about 5-7 psi at hot idle and this was factory spec. even at this low PSI it was safe if all bearings were seeing it.

 

when you get this engine rebuilt again I would suggest priming it with oil with the pan off to see where oil flow is escaping to.. you may need to block off  the oil coolers (if equipped) but it will hopeflully show whats getting oil and what is not.

 

one last thing. I have seen a few failed engines where the heavy use of gasket sealer during a rebuild (oil pan gasket) caused blockage in the pump and thru the block. the pump chews up the sealant and pushes it into the oil passages. just another variable to think about

[Hobert62]

Just a idea ..... But if this is the first they seen coated bearings is it possibles they put it together without assembly lube?    That could maybe explain all the bearings looking like this???  Maybe something this simple??  

[kevink1955]

I hope that engine was not put together in the same shop that took it apart after failure. That dirt floor is a show stopper, do you need operating room clean - no but at least a clean concrete floor.

[GreenGiant2]

Could the new block had the oil galleys full of crap and got pumped to bearings?