sansor

Hi,
This is new topic that has developed from my recent thread about this car loosing oil on the highway.

The car has finally been diagnosedis to have a "broken oil pump pick-up tube". This is said to be the cause of the engine running very hot and having oil level/oil pressure issues. Has anyone had this happen to their car(this one is a 82 911SC)? Does it happen when someone does work on the car, or can it just break? How is it repaired?

Any help very much appreciated.
Thanks
Bob

Peter Zimmermann

Bob: This is a weird one, can you please define "break." The tube is straight at one end, has a 90 degree bend at the other, and doesn't come into contact with anything. The straight end epoxys into the oil pump housing, the curved end terminates at the sump plate/screen. I've never seen a broken tube, but I've seen a few that were loose at the epoxy joint. As I read your description it almost sounds like somebody somehow managed to force the tube out of position, while installing the screen and cover plate, but for the life of me I can't figure out how.
Pete

sansor

Peter,
Thank you for your reply. I will get a better description of the damaged oil pick-up tube for you and post it here tomorrow. This engine has 132k miles and has never been rebuilt. I reviewed the service records over the last 7 years and the only service to this area was replacement of a gasket associated with the sump strainer a number of years ago (please understand I am a complete novice). Is this oil pick-up tube delicate and easily damaged? If this tube were damaged would it account for my engine overheating rapidly after only 20-30 miles on the highway?
Thanks
Bob

Peter Zimmermann

Bob: The tube is not delicate, and can be considered a lifetime part unless it was damaged during a work procedure. Regarding the gasket replacement, my shop took down the sump plate and screen and inspected/washed them at every major service. Therefore there was never a need to replace those gaskets. How the tube could relate to overheating is beyond me, but the actual damage might lend insight to the problem.
Pete

sansor

Hi Peter,
I have the information you requested. The mechanic just told me that when he took off the sump plate and took the strainer out, he found that the oil pick-up tube had detached from the oil pump at the epoxy connection. He said that the tube itself was damaged from contact with other parts in the engine and the tube not salvagible. He suggested that if another tube can be located it could be epoxied back into place? How does all this sound?
Bob

mo_gearhead

The oil pickup tube curves low to scavenge oil from the lower engine case. If it had fallen completely out of the pump housing it could rattle around and (I guess) come in contact with moving parts (crank, etc) and thus become damaged? The oil level in the crankcase would then rise higher than normal until it reached the now open sump pump hole. This might be the cause of your engine spraying oil, as I assume the higher oil volume might rise enough to contact the rotating parts ( crankshaft, rod ends, lay shaft, etc.) And on a Porsche (flat cylinder) engine, might throw excessive oil into the lower cylinder areas at speed?

Miguel

Ok. But is Sansor's problem an ugly one? Consider that this guy has happily acquired a porsche, his first, had a PPi ( sort of ) done, drove 60 miles, and the **** hits the fan...

Have we lost a Porsche guy due to malpractice, bad faith, act of God, or what?

Edward

Hi Bob,

Sorry I have nothing to offer here. But I do want to say that after following this and your other thread, I feel for you! We've all made decisions that we thought were good at the time, only to find out later that we should have done it differently. Welcome to the human race Take heart, sir. It is a lesson that is no doubt costing you frustration and money (we've all BTDT), but when all is said and done, you will be left with a car that I hope you can enjoy with huge grins!

Edward

Peter Zimmermann

Oh my. I guess if you could locate a used oil pump, remove the tube from it, and somehow get the pump in the engine clean enough to allow the epoxy to "take," then you should be alright. What I can't get my head wrapped around is how it could have come loose from the pump, it's held in place at the sump screen end, and shouldn't be able to move far enough to slip out of the pump. I'm missing something here, but if your mechanic can get the pump clean (MEK, swabs, etc.) he should be able to fix it. A used pump should be fairly easy to find. Let us know how it turns out!
Pete

madmmac

Pete, I don't think you are missing anything. The thing I think is missing is an honest previous owner and mechanic.

Hopefully no engine damage occurred from running it at those high temperatures.

Bob, if it was me, I would get all the parts, service records and paperwork and transport the car to another independent mechanic....Just my 2cents worth...

I'm pulling for both you and your car.

sansor

Peter,
The mechanic suggested that someone who replaced the strainer, cover plate and gaskets in January (as part of an oil leak fix-up) may have caused the damage.
The good news (and this has been the only good news for me and this car so far!) is that my mechanic has found a replacement oil pick-up tube!
My question to you is...if I was driving the car without this oil tube connected to the oil pump, could this account for my hot engine temps (bottom of the red zone and stayed there) when I got onto the highway at 55mph for the 20 miles? Is it reasonable for me to anticipate a cure from reattaching this tube? Will I then be allowed to drive and enjoy my Porsche like the other list members here?!?!?

***To everyone providing technical and emotional support - you have all helped to prevent me from becoming angry and bitter about this whole episode. I remain positive and hopeful that someday I will actually be able to drive this car that I bought!
Cheers
Bob

Peter Zimmermann

Bob: The 911 engine is incredibly durable, let's just hope that it will be OK once the pickup tube is in place. Insure that the oil level is correct when you pick up the car (middle of the dipstick, engine fully warmed up, car idling on level ground), and drive it very gingerly (but don't lug it) for a few hundred miles. Don't play the stereo during this time, you will want to be aware of any/all noises that your engine is making!
mad: Let's hope that Bob's car is in good hands this time around!
Pete

sansor

Pete,
Many thanks. I will follow your advice. I will provide an update soon (hopefully following an uneventful drive back to Maine in my new car!).
Best,
Bob

autobonrun

First, don't let a couple individuals make you sour on Porsche. It's a great car. I will not make any accusations I can't prove so I'll let you find where the blame lies, although I have my suspicions. Secondly, I can't believe this piece came loose during a 20 mile drive. I have to believe it was loose when you bought it.

With that said, I took a look at my Bentley manual. There is a schematic of the engine lubrication system on page 170-2. The scavenger pump pulls the oil from the sump via the infamous tube that broke and sends it to the thermostat. Based on the temperature of the oil some gets diverted to the aux oil cooler before it all gets sent to the oil tank reservoir. It is this reservoir that is the source for all the engine lubrication and for oil to the main oil cooler.

So to answer your earlier question, if the tube was not scavenging oil, none was going to the aux cooler or to the reservoir. This explains two things. One the car would overheat since no oil was getting to either cooler. Second, the oil level would rise in the sump since it is no longer being scavenged and sent to the reservoir. This would allow the rotating parts to slosh the oil out as you witnessed. I'm worried, but less so, about the cooling part of the circuit than the lubrication portion.

We have to hope that the period of time the engine ran without lubrication did not damage any of the moving parts. Since you pulled over you may have saved yourself an engine. And when they put it back together, have them make sure the screen is clear.

Thought of one more thing. You may have a saving grace, maybe two. Depending on where the inlet to the scavenger pump is located with respect to the oil level in the sump, you may have still got some oil into the system even though the pickup tube was off. Did you notice your oil pressure light on or a drop in the oil (druck) pressure while you were driving? If not you may have lady luck on your side. In addition, you would have still had some cooling of the heads from the fan.

sansor

Hi Autobonrun,
Your research and analysis is very helpful and much appreciated. At no time did any red warning lights appear. I seem to recall that the "Druck Pressure" remained in the mid range of the gauge. I do not think it fell during the "adventure". The engine still seemed to be running ok when I pulled over and stopped on the turnpike.
The prospect that repair of this oil pick-up tube may bring my car back to life has done a lot to improve my outlook.
-What a long strange trip it's been-
Bob