Disaster - oil pump failure?
12-01-2011, 07:04 PM
#1
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Disaster - oil pump failure?
My car has been in the shop having its annual "fix it so i don't have to worry about using it" list of things done. As a last item, I decide to follow the advice on the board and replace the oil lines from the thermostat with custom ones - again as per advice elsewhere on the board. So my shop takes off the lines but ends up putting most of the old ones back on as the custom shop cannot fabricate new ones. I go and collect it two weeks ago and the shop is just finishing off the task. I wait, they start the car and there is an intermittant rattle. After trying a couple more times, adding oil, they give me a lift home. Diagnosis at that stage was possible air in the lubrication system.
Cutting a long story short, I'm now told that the oil pump has failed and the engine needs replacing or rebuilding. They say the best economic option is a replacement engine due to cost of rebuild and what they may find.
I'm still somewhat in shock, and totally uncertain as to best approach. I've had the car for 12+ years, the engine has 75k miles on it but had solid as a bell oil pressure. I have no idea why the oil pump would have failed, or whether the decision to change the oil lines could have been a factor or what to do.
If anyone has any idea what could have caused the oil pump to fail, or whether stationary running of the engine and turning it off quickly as described above is likely to have resulted in other parts of the engine being damaged I'd be grateful for advice.
Given my druthers, I'd prefer not to put a replacement motor in there.
Cutting a long story short, I'm now told that the oil pump has failed and the engine needs replacing or rebuilding. They say the best economic option is a replacement engine due to cost of rebuild and what they may find.
I'm still somewhat in shock, and totally uncertain as to best approach. I've had the car for 12+ years, the engine has 75k miles on it but had solid as a bell oil pressure. I have no idea why the oil pump would have failed, or whether the decision to change the oil lines could have been a factor or what to do.
If anyone has any idea what could have caused the oil pump to fail, or whether stationary running of the engine and turning it off quickly as described above is likely to have resulted in other parts of the engine being damaged I'd be grateful for advice.
Given my druthers, I'd prefer not to put a replacement motor in there.
12-01-2011, 07:30 PM
#3
Three Wheelin'
ouch. say it's not so.
12-01-2011, 07:49 PM
#4
I dont understand why this is your problem? Your car was fine on arrival at the shop, then you watched them start the car and cause the failure. Seems like you'll be getting a free rebuild as a result of their error. Will take some negotiating hassle, but congrats.
12-01-2011, 07:52 PM
#5
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I'm waiting for wiser souls to comment, but my very first thought was particulate contamination from the oil line R&R.
Of course the shop would blame it all on a oil pump "failure".
Of course the shop would blame it all on a oil pump "failure".
12-01-2011, 08:05 PM
#7
Kind of weird, they typically do NOT have out of the blue oil pump failures.
something is not quite adding up, but nowhere near enough info to start pointing fingers or laying blame.
What kind of oil pressure does it have now.
Are they saying it's spun a con rod beaing? Which is probably what's rattling now.
Or what kind of rattle is it anyway. DMF? Chains? What?
Could have been a dirt in the oil system, but how it got past the filter is a bit of mystery (depending where it entered the system - i suppose) It would have had to been between the filter and the engine. Not sure what lines were changed or R&Red but most anything should have been picked up by the filter or dropped in the bottom of the tank.
I don't understand - WHY were the adding more oil? very curious. Did they not have any idea how much oil was in it? Very bad, very bad indeed. Always keep track of what comes out and what goes in. There is situations where there is no way to know for sure.
I also don't understand how a respectable Porsche shop could figure out how to get a few A&N SSB hoses made up. It's not that complicated.
While it is NOT recommended to let a 911 idle, but I don't how you could possible turn it off to quickly.
something is not quite adding up, but nowhere near enough info to start pointing fingers or laying blame.
What kind of oil pressure does it have now.
Are they saying it's spun a con rod beaing? Which is probably what's rattling now.
Or what kind of rattle is it anyway. DMF? Chains? What?
Could have been a dirt in the oil system, but how it got past the filter is a bit of mystery (depending where it entered the system - i suppose) It would have had to been between the filter and the engine. Not sure what lines were changed or R&Red but most anything should have been picked up by the filter or dropped in the bottom of the tank.
I don't understand - WHY were the adding more oil? very curious. Did they not have any idea how much oil was in it? Very bad, very bad indeed. Always keep track of what comes out and what goes in. There is situations where there is no way to know for sure.
I also don't understand how a respectable Porsche shop could figure out how to get a few A&N SSB hoses made up. It's not that complicated.
While it is NOT recommended to let a 911 idle, but I don't how you could possible turn it off to quickly.
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12-01-2011, 08:06 PM
#8
RL Technical Advisor
Porsche oil pumps are quite reliable and generally do not give trouble unless they "swallow" something.
Of that, I've seen my share and its always due to FOD (foreign object damage). In other words, human factors. I've found nuts, washers, bolts, circlips, and other assorted engine hardware jammed into the oil pump, locking the gears and damaging the case.
I'd go down to your shop and ask them for a "tour" of your engine. Find out how the oil pump failed: FOD or perhaps reassembled incorrectly if it was all apart.
Of that, I've seen my share and its always due to FOD (foreign object damage). In other words, human factors. I've found nuts, washers, bolts, circlips, and other assorted engine hardware jammed into the oil pump, locking the gears and damaging the case.
I'd go down to your shop and ask them for a "tour" of your engine. Find out how the oil pump failed: FOD or perhaps reassembled incorrectly if it was all apart.
12-01-2011, 08:48 PM
#9
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I can't quite decide which term sounds more technical: "FOD" or "particulate matter"
"FOD" sounds like something you'd feed your cat, whereas "particulate matter" is probably a bit redundant.
"FOD" is definitive in the sense that damage occured and it was caused by something which did not belong in the oil system such as "particulate matter".
In any case, please keep us all apprised and best of luck.
"FOD" sounds like something you'd feed your cat, whereas "particulate matter" is probably a bit redundant.
"FOD" is definitive in the sense that damage occured and it was caused by something which did not belong in the oil system such as "particulate matter".
In any case, please keep us all apprised and best of luck.
12-01-2011, 09:08 PM
#10
been there
I was pitting in at the track after a short session on a drying track, and I noticed the idiot light on and no guage pressure. I shut it down and coasted in I fired it up a couple of times after I checked the electrical connections, but it didn't sound right, so I had it towed home to try to figure it out. When I drained the oil, I found a chunk of the coupler laying there in the case.
I rebuilt the engine 2 years & 7,000 miles ago, and was just starting to feel comfortable that I got it right. When I split the case, the pump spun freely by hand. I flushed the pump through a strainer, and eventually took it apart. Never found any smoking gun. The oil pump strainers have a pretty tight mesh, so it seems more likely that something had to fall in there while it was apart or drain back down into it.
My damage was worst out on the cams and towers where it probably dried up first. The rods bottoms had to be resized, but the case and mains still were within spec. The pistons and cylinders were also okay.
Stay calm and don't jump to any conclusions. Hopefully your shop will work with you. The work on the oil lines seems like more than a coinsidance, but it would be hard to determine conclusively. I'd sure like to be there when the case was split.
YMMV but my guess is that repairing will be a better option, because 3.6s are not that easy to come by.
I rebuilt the engine 2 years & 7,000 miles ago, and was just starting to feel comfortable that I got it right. When I split the case, the pump spun freely by hand. I flushed the pump through a strainer, and eventually took it apart. Never found any smoking gun. The oil pump strainers have a pretty tight mesh, so it seems more likely that something had to fall in there while it was apart or drain back down into it.
My damage was worst out on the cams and towers where it probably dried up first. The rods bottoms had to be resized, but the case and mains still were within spec. The pistons and cylinders were also okay.
Stay calm and don't jump to any conclusions. Hopefully your shop will work with you. The work on the oil lines seems like more than a coinsidance, but it would be hard to determine conclusively. I'd sure like to be there when the case was split.
YMMV but my guess is that repairing will be a better option, because 3.6s are not that easy to come by.
My car has been in the shop having its annual "fix it so i don't have to worry about using it" list of things done. As a last item, I decide to follow the advice on the board and replace the oil lines from the thermostat with custom ones - again as per advice elsewhere on the board. So my shop takes off the lines but ends up putting most of the old ones back on as the custom shop cannot fabricate new ones. I go and collect it two weeks ago and the shop is just finishing off the task. I wait, they start the car and there is an intermittant rattle. After trying a couple more times, adding oil, they give me a lift home. Diagnosis at that stage was possible air in the lubrication system.
Cutting a long story short, I'm now told that the oil pump has failed and the engine needs replacing or rebuilding. They say the best economic option is a replacement engine due to cost of rebuild and what they may find.
I'm still somewhat in shock, and totally uncertain as to best approach. I've had the car for 12+ years, the engine has 75k miles on it but had solid as a bell oil pressure. I have no idea why the oil pump would have failed, or whether the decision to change the oil lines could have been a factor or what to do.
If anyone has any idea what could have caused the oil pump to fail, or whether stationary running of the engine and turning it off quickly as described above is likely to have resulted in other parts of the engine being damaged I'd be grateful for advice.
Given my druthers, I'd prefer not to put a replacement motor in there.
Cutting a long story short, I'm now told that the oil pump has failed and the engine needs replacing or rebuilding. They say the best economic option is a replacement engine due to cost of rebuild and what they may find.
I'm still somewhat in shock, and totally uncertain as to best approach. I've had the car for 12+ years, the engine has 75k miles on it but had solid as a bell oil pressure. I have no idea why the oil pump would have failed, or whether the decision to change the oil lines could have been a factor or what to do.
If anyone has any idea what could have caused the oil pump to fail, or whether stationary running of the engine and turning it off quickly as described above is likely to have resulted in other parts of the engine being damaged I'd be grateful for advice.
Given my druthers, I'd prefer not to put a replacement motor in there.
12-01-2011, 09:09 PM
#11
RL Technical Advisor
I can't quite decide which term sounds more technical: "FOD" or "particulate matter"
"FOD" sounds like something you'd feed your cat, whereas "particulate matter" is probably a bit redundant.
"FOD" is definitive in the sense that damage occured and it was caused by something which did not belong in the oil system such as "particulate matter".
In any case, please keep us all apprised and best of luck.
"FOD" sounds like something you'd feed your cat, whereas "particulate matter" is probably a bit redundant.
"FOD" is definitive in the sense that damage occured and it was caused by something which did not belong in the oil system such as "particulate matter".
In any case, please keep us all apprised and best of luck.
12-01-2011, 09:16 PM
#12
RL Technical Advisor
Remember now, the strainer is the intake for the scavenge side: the pressure side is fed directly from the tank so any FO in the hose or tank can be pulled right into the oil pump gears.
12-01-2011, 09:23 PM
#13
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If they had the lines off then the car had probably been drained of oil. Did the pump have time to prime? Was any attempt made to get the oil pressure up before actually starting the car?
12-01-2011, 09:41 PM
#14
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I really, really appreciate all the help and input. Answering some of the questions - and in search of root cause and anything that may help me understand whether a full rebuild is needed
- Did the pump have time to prime? Was any attempt made to get the oil pressure up before actually starting the car? No, battery was put on a charger and then started. I did not see any thing done to get the oil pressure up before the car was started.
- What kind of oil pressure does it have now. I'm told zero
- Or what kind of rattle is it anyway I wish I could describe it better - but a it did not sound tinny metallic, rather a deep (expensive) one. It did sound like it came from deep in the bay - like the cylinder area but the more I try and remember the more my current state of shock kicks in, sorry.
- I don't understand - WHY were the adding more oil? I don't know. It was a topping up rather than adding liters....
- Remember now, the strainer is the intake for the scavenge side: the pressure side is fed directly from the tank so any FO in the hose or tank can be pulled right into the oil pump gears. I was told that there was nothing in the mesh.
Again, thanks for all the help. Truly appreciated.
-
- Find out how the oil pump failed: FOD or perhaps reassembled incorrectly if it was all apart. Agreed. The pump was not taken apart - while both banks of timing cover gaskets were replaced and the front crankshaft seal was replaced, the rest of the work was on the power steering, suspension and those oil lines.
- Did the pump have time to prime? Was any attempt made to get the oil pressure up before actually starting the car? No, battery was put on a charger and then started. I did not see any thing done to get the oil pressure up before the car was started.
- What kind of oil pressure does it have now. I'm told zero
- Or what kind of rattle is it anyway I wish I could describe it better - but a it did not sound tinny metallic, rather a deep (expensive) one. It did sound like it came from deep in the bay - like the cylinder area but the more I try and remember the more my current state of shock kicks in, sorry.
- I don't understand - WHY were the adding more oil? I don't know. It was a topping up rather than adding liters....
- Remember now, the strainer is the intake for the scavenge side: the pressure side is fed directly from the tank so any FO in the hose or tank can be pulled right into the oil pump gears. I was told that there was nothing in the mesh.
Again, thanks for all the help. Truly appreciated.
-
- Find out how the oil pump failed: FOD or perhaps reassembled incorrectly if it was all apart. Agreed. The pump was not taken apart - while both banks of timing cover gaskets were replaced and the front crankshaft seal was replaced, the rest of the work was on the power steering, suspension and those oil lines.
12-01-2011, 10:15 PM
#15
Zero pressure and it makes noise. Is the pump that is making noise? Broken? shaft broke?
Spun bearings will often have oil pressure because the hole is plugged. Plus it will make a knock not a rattle.
how long did it run without pressure. If it wasn't that long and it was a pump it might not be that bad. It sounds like taking it down to splitting the case but it might not need a whole lot of hard parts.
Spun bearings will often have oil pressure because the hole is plugged. Plus it will make a knock not a rattle.
how long did it run without pressure. If it wasn't that long and it was a pump it might not be that bad. It sounds like taking it down to splitting the case but it might not need a whole lot of hard parts.