Need Adivse. Possible Rear Main Leak!!!
09-21-2008, 06:27 PM
#1
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Need Adivse. Possible Rear Main Leak!!!
Ok people. I have a nice leak coming from underneath the flywheel area. I jacked my car up and noticed some oil sitting directly undernearth the rear main seal right in front of the oil pan gasket. I took a rag and wiped it clean. Moments later I noticed the oil instantly apear traviling from on top of the rear seal resting right in front of the oil gasket directly behind the flywheel. At first I thought it was my intake manifold gasket. So I went on ahead and resealed that yesterday. It turns out that is incorrect. When I first put the motor in and added oil to the pan (canton 6qt) I started the motor and noticed my oil gauge reading over 90psi on idol. Ok I admit it. I put too much oil in the motor. After a couple of runs I did notice oil starting to come out of places that I described earlier in this post. Now at this point I called canton and a tried to get info on my pan. The tech guy said if you put too much oil in the motor the rear main seal will leak and it will not seal again. (Im thinking ohhhh skit) Im almost positive that the rear main is leaking. IM running Castrol GTX oil 5w-30. IS it possible oil could be coming from somehwere else.?
Chris
Chris
09-22-2008, 02:01 AM
#2
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You have ruled out the intake manifold leak, and as long as it isn't the oil pan gasket itself that is leaking because the pan is to full, the real main seal is the likely source. Sounds like this is a relatively new motor, any chance the seal was installed backwards?
09-22-2008, 10:26 AM
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I dont believe the seal was installed backwards. Theres only one way for it to go on. I have a new Canton Oil pan with felpro gasket. So no leaks there. When I first put the oil in there was no leaks until after finding out I had too much oil in it. I started to see oil coming out. I have resealed my intake manifold. NO leaks there. Theres gotta be a way to stop that leak without pulling the motor. Or swaping it out while motor is in the car. Maybe some sealant or something.
Chris
Chris
Two options, drop the trans, or pull the motor.
09-22-2008, 11:23 AM
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Gator,
You coudnt have put that any simpler. I was afraid of that BUt I have to face it. Thats the only way to see whats going on. Other than the leak. The motor is running good. I need more tranny fluid in the trans because its taking for ever to shift. Thanks for the help.
Chris
You coudnt have put that any simpler. I was afraid of that BUt I have to face it. Thats the only way to see whats going on. Other than the leak. The motor is running good. I need more tranny fluid in the trans because its taking for ever to shift. Thanks for the help.
Chris
09-22-2008, 12:38 PM
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Can somone Confirm this information,
A good friend of mine told me that he doesnt think its the rear main seal leaking. I asked him why? He said if it was the rear main seal it would leak while the motor is off not while its running. Reason being is that the rear main seal while rotating on the crank is sealing the crank. And that when it stops. The oil would leak through. I think he might be right. It only leaks when the motor is running. Also another theory. After taking it around the corner I noticed oil sitting on the passenger side valve cover. I had to double gasket the valve covers so that i had enough clearance for the rockers. Im wondering if the Double gaskets is causing some issues. Oil on the valve covers is a good indication of that.
Chris
A good friend of mine told me that he doesnt think its the rear main seal leaking. I asked him why? He said if it was the rear main seal it would leak while the motor is off not while its running. Reason being is that the rear main seal while rotating on the crank is sealing the crank. And that when it stops. The oil would leak through. I think he might be right. It only leaks when the motor is running. Also another theory. After taking it around the corner I noticed oil sitting on the passenger side valve cover. I had to double gasket the valve covers so that i had enough clearance for the rockers. Im wondering if the Double gaskets is causing some issues. Oil on the valve covers is a good indication of that.
Chris
09-22-2008, 12:56 PM
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Wow...
You need to feel around the engine to see where the leak is originating. Theoretically an engine should never have oil residing anywhere on the outside so if you feel oil do not dismiss it as it being there for any given reason. You need to investigate. Start at the top of the engine around the intake manifold seals and valve covers since those are the most popular places for oil to leak at least on the LT1 and work your way down. Nine times out of ten it is not the rear main.
Yes using two gaskets can cause problems. You've just increased the network of avenues for oil to escape.
Your friend is wrong. If the seal is bad it will not stop oil from leaking while the engine is running. The rear main is like any other oil seal.
You need to feel around the engine to see where the leak is originating. Theoretically an engine should never have oil residing anywhere on the outside so if you feel oil do not dismiss it as it being there for any given reason. You need to investigate. Start at the top of the engine around the intake manifold seals and valve covers since those are the most popular places for oil to leak at least on the LT1 and work your way down. Nine times out of ten it is not the rear main.
Yes using two gaskets can cause problems. You've just increased the network of avenues for oil to escape.
Your friend is wrong. If the seal is bad it will not stop oil from leaking while the engine is running. The rear main is like any other oil seal.
09-22-2008, 03:12 PM
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SS RRR
Good info thank you. Now that I think about it. Initially in the begining stages of my start up and prior to me going getto with my valve cover gasket LOL I had the covers off adjusting the valves. I had rags protecting the headers. While the motor was running (this was also when I had too much oil in the motor) I did not notice any oil at all. Since the getto install. I did a oil change and started noticing the oil on the ground. Also on the passenger side valve cover Ive noticed oil collecting. I really hope that its not the rear main due to me over filling the pan. It seems like it would be impossible for a rear seal to leak because of its snuggness, but that doesn't mean anything. 60psi of pressure anything could happen,
Chris
Good info thank you. Now that I think about it. Initially in the begining stages of my start up and prior to me going getto with my valve cover gasket LOL I had the covers off adjusting the valves. I had rags protecting the headers. While the motor was running (this was also when I had too much oil in the motor) I did not notice any oil at all. Since the getto install. I did a oil change and started noticing the oil on the ground. Also on the passenger side valve cover Ive noticed oil collecting. I really hope that its not the rear main due to me over filling the pan. It seems like it would be impossible for a rear seal to leak because of its snuggness, but that doesn't mean anything. 60psi of pressure anything could happen,
Chris
09-22-2008, 04:53 PM
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The oil at the rear main seal is not under pressure from the oiling system. If it were, there would be a MUCH bigger leak. I can understand how an excessive amount of oil in the pan could result in greater accumulation of oil in the area of the seal but it would be only be pressurized to the level that ring blow-by into the pan created. If the motor was very loose (as in worn out or as the result of unseated compression rings, the pressure in the pan could cause oil to be forced out at the seal.
09-22-2008, 05:18 PM
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Do you have a PCV system connected or, if not, do you have breathers on the valve covers? If you have either of these systems in place, the crankcase pressure would have to be very high to force oil past the seal. I've only experienced it once, at the end of a full quarter-mile pass that I inadvertently made with the with the PVC hose plugged. I swapped out the seal immediately after that happened. I think you would be well-advised to make absolutely sure that the oil is not coming from some other source before you drop the trans or pull the motor. The stacked valve cover gaskets are a likely source.
Good luck.
Good luck.
09-22-2008, 07:39 PM
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pcv iis hooked up. however thee valve cover breather is hooked up too. im using to stock covers and i had to pull out webs on the valve covers to get them to fit. on the passenger side were the breather is hooked up. i had to pull out the portion that directly underneath the breather. wheb it get home im going to start the motor and pull off the covers and place raggs to catch the oil. to see if it leaks
chris
chris
09-22-2008, 09:31 PM
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pcv iis hooked up. however thee valve cover breather is hooked up too. im using to stock covers and i had to pull out webs on the valve covers to get them to fit. on the passenger side were the breather is hooked up. i had to pull out the portion that directly underneath the breather.
What kind of "magnum" rockers are you using? If they are Pro Magnum rockers there is no reason for you to pull out the baffle and all the braces or to double gasket stock valve covers. Please do a search on "clearencing valve covers" and you'll pull up dozens and dozens of threads on how to do this properly.
If your stock PCV system is in tact then a breather is absolutely not necessary.
Last edited by SS RRR; 09-22-2008 at 09:34 PM.
09-23-2008, 01:15 AM
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SS RRR.
Well I think I figured it out. Just a little while ago I took off my valve covers and placed raggs over the headers just to see if my theory was right on the valve cover leaking. Result, Negative. It still leaked right in front of the oil pan gasket directly behind the flex plate. The next step? At this point the car was jacked up in the air. While under the car I wiped clean the oil sitting there directly under the rear seal on the metal surface in front of the oil pan gasket. I started the motor. I quickly dashed underneath the car and notice no oil dripping. About a min passed and I saw Oil Traveled from the somewhere around the top of the seal cover and rested at the 6 o clock position which is directly in front of the gasket behind the flex plate etc.. Im about 75% sure my rear main seal is the problem. I can't think of any other place as to where the oil is coming from. As far as the rocker arms. Ill have to get a part number for you tomorrow sometime. But I do know that they are PRO form Magnum Rockers Full roller SBC. 3/8 studs. WHen I placed the stock covers on, the webs did not fit in between the rockers. I did do some research on that and others concluded to ither pinch the webs with plyers. Or pull them out. I choose to pull them out. After pulling the webs out I placed the valve covers on and they still didnt fit. So my mind was thinking. Double up on the gaskets to provide the nessary clearance I need. I did and it fit just fine. However at this point I have s*it canned those covers and waiting to get the right ones. As far as the leak. Im gonna have to do what you said. DROP the tranny. What do you all think NOW??
Chris
Well I think I figured it out. Just a little while ago I took off my valve covers and placed raggs over the headers just to see if my theory was right on the valve cover leaking. Result, Negative. It still leaked right in front of the oil pan gasket directly behind the flex plate. The next step? At this point the car was jacked up in the air. While under the car I wiped clean the oil sitting there directly under the rear seal on the metal surface in front of the oil pan gasket. I started the motor. I quickly dashed underneath the car and notice no oil dripping. About a min passed and I saw Oil Traveled from the somewhere around the top of the seal cover and rested at the 6 o clock position which is directly in front of the gasket behind the flex plate etc.. Im about 75% sure my rear main seal is the problem. I can't think of any other place as to where the oil is coming from. As far as the rocker arms. Ill have to get a part number for you tomorrow sometime. But I do know that they are PRO form Magnum Rockers Full roller SBC. 3/8 studs. WHen I placed the stock covers on, the webs did not fit in between the rockers. I did do some research on that and others concluded to ither pinch the webs with plyers. Or pull them out. I choose to pull them out. After pulling the webs out I placed the valve covers on and they still didnt fit. So my mind was thinking. Double up on the gaskets to provide the nessary clearance I need. I did and it fit just fine. However at this point I have s*it canned those covers and waiting to get the right ones. As far as the leak. Im gonna have to do what you said. DROP the tranny. What do you all think NOW??
Chris