oil Leak
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oil Leak
I hope someone may be able to point me in the right direction .I just noticed an oil leak on my 2003 c5 .Most of the oil is on the driver's side leaf spring clamp.And it drips off from there .
I spent a few hours looking today and did not find any obvious leak >I also looked with the engine running So it seems to be a slow leak .
Thanks for any help with this.
I spent a few hours looking today and did not find any obvious leak >I also looked with the engine running So it seems to be a slow leak .
Thanks for any help with this.
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The leaf spring is under the power steering hoses and pump. It is also under the harmonic balancer which is the front seal surface.
See if you are low on power steering fluid.
Put your hand behind the harmonic balancer and see if there is fresh oil in that area. Then the front seal may be leaking. If so then a possible cause may be bad harmonic balancer. See if the balancer is coming loose or wobbling.
If the oil is coming from somewhere else on the engine then you may have too much pressure in the crank case caused by a bad PCV valve or inadequate crank case ventilation.
See if you are low on power steering fluid.
Put your hand behind the harmonic balancer and see if there is fresh oil in that area. Then the front seal may be leaking. If so then a possible cause may be bad harmonic balancer. See if the balancer is coming loose or wobbling.
If the oil is coming from somewhere else on the engine then you may have too much pressure in the crank case caused by a bad PCV valve or inadequate crank case ventilation.
Last edited by Rob 02; Nov 16, 2017 at 09:26 PM.
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It can leak out of any of the gaskets including the front cover, oil pan, etc... but it is less likely unless you have a PCV problem, excessive blow by from low compression or someone worked on it without lining the engine covers properly.
Do you have any engine mods and is it a Z06?
Do you have any engine mods and is it a Z06?
Last edited by Rob 02; Nov 16, 2017 at 10:41 PM.
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It's totally stock . I have had it for about 4 years now . It s been good . Regular oil change and I do look after it well . She runs really good . Can't fault it . The oil I see looks really clean as well . I will check over the pcv system as well just to make sure . From what you say it surely is pointing to front oil seal !
and it's not a zo6
and it's not a zo6
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The only reason I asked if it was modified or a Z is because the '02-'03 PCV left something to be desired IMO that was fixed in "04. I don't think that is a concern in your case.
If it is a front seal then it the leak could still be caused by PCV but is more likely a worn harmonic balancer. There is no shortage of threads covering the balancer issue. It is time consuming to fix because of the rack an pinion is in the way.
If it is a front seal then it the leak could still be caused by PCV but is more likely a worn harmonic balancer. There is no shortage of threads covering the balancer issue. It is time consuming to fix because of the rack an pinion is in the way.
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If the pcv system is bad , is there any test for the system. Would the pressure be noticeable at the dipstick .
as much as I do look after this car , I drive it quite hard , so I would think the system would have a good blowout !
as much as I do look after this car , I drive it quite hard , so I would think the system would have a good blowout !
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From: Atlantic Beach FL.
I would buy a valve and compare them. It is probably due for a new one any way. If it stops leaking then you are good.
Check the balancer for wobble or misalignment with the belts.
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i had the same small leak on the driver's side leaf spring clamp it was the block oil galley plug , post #3 ,the small plug by the bar code label
https://www.corvetteforum.com/forums...post1557077194
https://www.corvetteforum.com/forums...post1557077194
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I have just had a good look again .It looks clean and dry on and around the balancer .I have just degrease the area so will go and have a look when its dry.
I will look for the oil galley plug that 89 Nascar mentioned .
I will look for the oil galley plug that 89 Nascar mentioned .
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From: Atlantic Beach FL.
I hope for your sake it is not leaking from the front seal. I would think that the front seal would leak from the middle or both sides.
Those galley plugs are beefy. I cant imagine what would cause one to leak but if that's where the leak is then it's a much easier fix.
Good luck.
Those galley plugs are beefy. I cant imagine what would cause one to leak but if that's where the leak is then it's a much easier fix.
Good luck.
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I hope for your sake it is not leaking from the front seal. I would think that the front seal would leak from the middle or both sides.
Those galley plugs are beefy. I cant imagine what would cause one to leak but if that's where the leak is then it's a much easier fix.
Good luck.
Those galley plugs are beefy. I cant imagine what would cause one to leak but if that's where the leak is then it's a much easier fix.
Good luck.
It looks like its coming from the seal between the upper oil pan and block .Its only on the very corner above the leaf spring where the block protrude further that the oil pan .Under idle I can see oil sweating out .The bolts would not snug up any more .
Now that it is all clean I will monitor the area and make sure before i start taking it apart .
Any tips on exposing the oil pan for removal ?
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You have to be careful and here is why? The front cover and rear cover contain the front and rear oil seals. The bottom of the covers run flush with the block and are part of the oil pan's mating surface. There are pan bolts that fasten into the front and rear covers.
You also really need to follow the torque spec of the bolts to avoid further leaks.
You don't want to mess with the alignment of the front and rear seals or you will have bigger problems.
With that said I think the leak is where the block, front cover and pan meet. I usually put RTV in that crack before installing the pan.
This video in You Tube isn't the best but it shows the area of concern if you are not familiar with it.
You also really need to follow the torque spec of the bolts to avoid further leaks.
You don't want to mess with the alignment of the front and rear seals or you will have bigger problems.
With that said I think the leak is where the block, front cover and pan meet. I usually put RTV in that crack before installing the pan.
This video in You Tube isn't the best but it shows the area of concern if you are not familiar with it.
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Hey Rob ,Thats a good video. Thanks and I really appreciate your advice.
So looking at the video ,I would say the leak is actually where the bottom of the front cover meets the oil pan.
Now the question is :Is it easier to remove the front cover and reseal it or drop the oil pan .
If I drop the oil pan I think I do not have to disturb the front or rear covers but if I can sort it out by resealing the front cover ,
I can renew the front oil seal at the same time .(Although front oil seal is good and the rest of the sump is sound as well)
The car now has 143000 miles .
Your thoughts?
So looking at the video ,I would say the leak is actually where the bottom of the front cover meets the oil pan.
Now the question is :Is it easier to remove the front cover and reseal it or drop the oil pan .
If I drop the oil pan I think I do not have to disturb the front or rear covers but if I can sort it out by resealing the front cover ,
I can renew the front oil seal at the same time .(Although front oil seal is good and the rest of the sump is sound as well)
The car now has 143000 miles .
Your thoughts?
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I would have to think about this because if it is not leaking from the front seal then you shouldn't touch the front cover otherwise you might cause an alignment issue.
I personally would rather remove the pan if that is possible for you. The pan gasket is probably not in good shape. The gasket has a metal frame with a O ring sort of seal surface, as with the rest of the engine gaskets. the rubber gets crushed over time and some times comes apart from the metal. You will want the appropriate RTV in the four corners.
I never tried to remove the upper pan with the engine installed. You might have to lower the engine cradle a little on its bolts and loosen the engine mounts and hoist the engine up a little. You need enough clearance to get a new gasket in there. The mounting surfaces need to be dry of oil. It will take some attention to detail.
I personally would rather remove the pan if that is possible for you. The pan gasket is probably not in good shape. The gasket has a metal frame with a O ring sort of seal surface, as with the rest of the engine gaskets. the rubber gets crushed over time and some times comes apart from the metal. You will want the appropriate RTV in the four corners.
I never tried to remove the upper pan with the engine installed. You might have to lower the engine cradle a little on its bolts and loosen the engine mounts and hoist the engine up a little. You need enough clearance to get a new gasket in there. The mounting surfaces need to be dry of oil. It will take some attention to detail.
Last edited by Rob 02; Nov 18, 2017 at 05:07 PM.
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I would have to think about this because if it is not leaking from the front seal then you shouldn't touch the front cover otherwise you might cause an alignment issue.
I personally would rather remove the pan if that is possible for you. The pan gasket is probably not in good shape. The gasket has a metal frame with a O ring sort of seal surface, as with the rest of the engine gaskets. the rubber gets crushed over time and some times comes apart from the metal. You will want the appropriate RTV in the four corners.
I never tried to remove the upper pan with the engine installed. You might have to lower the engine cradle a little on its bolts and loosen the engine mounts and hoist the engine up a little. You need enough clearance to get a new gasket in there. The mounting surfaces need to be dry of oil. It will take some attention to detail.
I personally would rather remove the pan if that is possible for you. The pan gasket is probably not in good shape. The gasket has a metal frame with a O ring sort of seal surface, as with the rest of the engine gaskets. the rubber gets crushed over time and some times comes apart from the metal. You will want the appropriate RTV in the four corners.
I never tried to remove the upper pan with the engine installed. You might have to lower the engine cradle a little on its bolts and loosen the engine mounts and hoist the engine up a little. You need enough clearance to get a new gasket in there. The mounting surfaces need to be dry of oil. It will take some attention to detail.
Im a bit confused on why removing the front cover ,which is the timing chain cover would or can cause 'an alignment issue'. I would think the cover can only go in one way?
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There is an alignment tool you need to get it perfectly centered. If it is not perfectly centered then it will leak out of the front seal. The front seal surface rides on the harmonic balancer which will be removed.
To get the harmonic balancer of you will have to remove the rack and pinion so it is not necessarily the easier route.
If you do remove the front cover then it's a good time to decide if you want to do a cam swap.
To get the harmonic balancer of you will have to remove the rack and pinion so it is not necessarily the easier route.
If you do remove the front cover then it's a good time to decide if you want to do a cam swap.
Last edited by Rob 02; Nov 19, 2017 at 08:20 PM.