Minor oil leak near Crankshaft Position Sensor
#1
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While looking underneath the car, I noticed a minor leak at the back of the engine, in the area where the crankshaft position sensor is. Pic attached.
The leak seems to be originating from the bolt, left to the crankshaft position sensor. Opening up the rubber seal below it (which gives access to the flywheel), the flywheel is dry and there is no sign of oil on the flywheel. It seems that the oil is dripping by the side and with the car movement is then dragged on the gearbox enclosure surface side.
The Jag technician has cleaned the area, asked me to drive it for a couple of weeks and get back to him to see whether the leak is still there and to what extent, in which case the bolt will be removed and reseated with a sealer to it. Seems like a reasonable approach to me.
Anyone of you ever encountered such an issue? What might have caused such a leak? Could a recent oil change have played a part?
Cheers!
PS: Vehicle is a MY2009 4.2L SC Conv, 25k miles
The leak seems to be originating from the bolt, left to the crankshaft position sensor. Opening up the rubber seal below it (which gives access to the flywheel), the flywheel is dry and there is no sign of oil on the flywheel. It seems that the oil is dripping by the side and with the car movement is then dragged on the gearbox enclosure surface side.
The Jag technician has cleaned the area, asked me to drive it for a couple of weeks and get back to him to see whether the leak is still there and to what extent, in which case the bolt will be removed and reseated with a sealer to it. Seems like a reasonable approach to me.
Anyone of you ever encountered such an issue? What might have caused such a leak? Could a recent oil change have played a part?
Cheers!
PS: Vehicle is a MY2009 4.2L SC Conv, 25k miles
#3
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amc, I would prefer a shiny shiny one on which I can put on my personal graffiti ![Smile](https://www.jaguarforums.com/forum/images/smilies/smile.gif)
Doing some more research, mostly here, I think the possibilities are as follows:
1 rear main seal (I'm finding this difficult to accept); would this show as oil splattered all over the flywheel?
2 seals between the various engine block components inside the flywheel housing;
3 the hex galley nut on the engine side inside the housing; (see thread https://www.jaguarforums.com/forum/x...leaking-38555/. It's not an XKR, but the engine seems to be quite similar;
4 are the two circular things just below this nut, plugs which could leak?
I suppose the transmission needs to be removed
Any estimates of time to do this?
so not looking forward to this ....
![Smile](https://www.jaguarforums.com/forum/images/smilies/smile.gif)
Doing some more research, mostly here, I think the possibilities are as follows:
1 rear main seal (I'm finding this difficult to accept); would this show as oil splattered all over the flywheel?
2 seals between the various engine block components inside the flywheel housing;
3 the hex galley nut on the engine side inside the housing; (see thread https://www.jaguarforums.com/forum/x...leaking-38555/. It's not an XKR, but the engine seems to be quite similar;
4 are the two circular things just below this nut, plugs which could leak?
I suppose the transmission needs to be removed
![Frown](https://www.jaguarforums.com/forum/images/smilies/frown.gif)
so not looking forward to this ....
#4
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Update:
Car at dealer; transmission removed. Have been informed that leak is coming from ... wait for it ... the hex plug in the cylinder block on the engine side, on top of the rear main seal. It seems that there's a slight leak here which is dripping on the engine side of the bellhousing, making it's way down. As mentioned in 'Option 3' below, although it's not the same car and the plug may not be 'loose' but the seal leaking. Rear main seal is ok, thank god for that!
Plug and sealing washer will be replaced.
Removing transmission is not trivial; needs removal of cat converters, exhaust system, draining of AC refrigerant, removal 'R' exhaust vacuum pump, etc. A couple of days work at dealer.
Of course, I'm taking this up with Jaguar as I don't think that this should really be happening.
I'll be going to see the car in surgery tomorrow, take some photos and post.
Any ideas of why something like this would happen? Maybe lack of previous owner use?
Car at dealer; transmission removed. Have been informed that leak is coming from ... wait for it ... the hex plug in the cylinder block on the engine side, on top of the rear main seal. It seems that there's a slight leak here which is dripping on the engine side of the bellhousing, making it's way down. As mentioned in 'Option 3' below, although it's not the same car and the plug may not be 'loose' but the seal leaking. Rear main seal is ok, thank god for that!
Plug and sealing washer will be replaced.
Removing transmission is not trivial; needs removal of cat converters, exhaust system, draining of AC refrigerant, removal 'R' exhaust vacuum pump, etc. A couple of days work at dealer.
Of course, I'm taking this up with Jaguar as I don't think that this should really be happening.
I'll be going to see the car in surgery tomorrow, take some photos and post.
Any ideas of why something like this would happen? Maybe lack of previous owner use?
#6
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Thread resurrection time. I have similar on my own car, 2008 4.2 XKR, see pic below:
![Minor oil leak near Crankshaft Position Sensor-losz6lp.jpg](https://www.jaguarforums.com/forum/attachments/xk-xkr-x150-33/225795d1683067080t-minor-oil-leak-near-crankshaft-position-sensor-losz6lp.jpg)
So am I right in thinking there shouldn't be any oil in there in the first place, let alone leaking out? If it is leaking through one of the seals, is it possible this could be due to slightly over-filled oil level?
![Minor oil leak near Crankshaft Position Sensor-losz6lp.jpg](https://www.jaguarforums.com/forum/attachments/xk-xkr-x150-33/225795d1683067080t-minor-oil-leak-near-crankshaft-position-sensor-losz6lp.jpg)
So am I right in thinking there shouldn't be any oil in there in the first place, let alone leaking out? If it is leaking through one of the seals, is it possible this could be due to slightly over-filled oil level?
#7
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#9
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Thank you both. The leak showed up on the MOT test (as an advisory, not a fail) and the technician seemed pretty certain it was engine oil as opposed to transmission fluid so it doesn't sound like it's coming from the transmission unit.
ejjbee, how many hours' labour did it take to get yours fixed, can you remember?
ejjbee, how many hours' labour did it take to get yours fixed, can you remember?
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#13
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So that's all correct, the trouble is that the leak was observed at the annual MOT test and is recorded as an advisory item. In the UK, the MOT test results of any vehicle are available as public records so any astute buyer would check and potentially be put off by that, also I can see if I was trading the car in at a franchised or independent dealer they may use that to use as an excuse to offer a lower trade-in value and at the moment I am thinking of changing the car.
Also, if it is the crankshaft main seal, is there not the potential that the leak could get worse and result in a bigger issue come time?
Also, if it is the crankshaft main seal, is there not the potential that the leak could get worse and result in a bigger issue come time?
#14
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8bit, if I remember correctly it must have taken some 2days of work. It didn't seem a trivial job, as the transmission had to be removed. And to do that they needed to start with removing the exhaust system from the back, then the transmission itself. I think I had paid some Eur900 for the whole job, including a Eur5 or so failed culprit washer!
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#19
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Trans service was done I think about 10k miles ago, but the trans fluid cooler lines have to come off so I guess that'd really mean dropping most of the fluid to do properly anyway. If I'm going to have this done then may as well have it all done right, just weighing up the potential costs and benefits right now.
#20
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I get to look under my car every day as I move my daily driver out from under the lift. I must say looking at it it appears to me that removal of the transmission is pretty straight forward and my guess would be maybe 4 hours. The exhaust is under everything so that just drops out and the shielding and prop shaft looks pretty simple. I guess if I were to do it maybe 2 days is sufficient but for a dealer it shouldn't take more then a day. I wonder what the book time is.