Oil leaking problem......
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Oil leaking problem...... I have had a oil leak in my new motor for awhile now. First it was leaking BAD and I thought the culprit was the valve cover gaskets and the oil dipstick, which both of them were leaking. I fixed those and now it looks like the rear main is leaking and also the front crank seal.
One thing I did notice is while running the car at the track today, my oil pressure was HIGH. Something around the 3rd mark on the gauge.
Now I am running the same oil pump that was in my old motor. But could the crankcase be building too much pressure?? Or could the guy that put the motor together really just have messed up all those seals?
One thing I did notice is while running the car at the track today, my oil pressure was HIGH. Something around the 3rd mark on the gauge.
Now I am running the same oil pump that was in my old motor. But could the crankcase be building too much pressure?? Or could the guy that put the motor together really just have messed up all those seals?
With a welded pick up and running heavy weight oil, the pressure is where mine is at. I also run a breather on both VCs. Oh and the hose is the one that goes from the PS VC to the TB
How did the car do at the track?
How did the car do at the track?
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Not good at all. I did a couple off idle runs and my MPH was WAY lower than it should have been. I was barely trapping over 100 MPH. I launched it a few times and MPH was the same but of course the ET was better since I was coming out of the hole harder. It hooked decent on a set of 26" tall 17" ET streets.
I'm still having oil leaking problems. I was sure it was coming from my rear main seal and am going to replace that but not it looks like it is coming from the front crank seal as well.
The tune is not even close, so I am hoping that will take car of the problem. The first run it seemed to be cutting out up top like it was running out of fuel or retarding the timing. Hopefully I will get those fixed this weekend.
As far as the oil leaking goes, I really hope it was just incompetance putting the thing together. I had a guy put my bottom end together since he did the balancing and machine work and I figured it would save me some time. I will NEVER do that again. I have had nothing with problems with this thing from the first day I started it. I am really almost to the point of pulling the motor completely again and rebuilding it myself to make sure nothing else is wrong with it, especially since all these little things are stuff that any good engine bulider would not have overlooked.
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I took that off and replace it with a breather, could that be the problem? should I go ahead and leave that on there?
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Your Oil pressure is too high if you are running 5w30 synthetic 
IMO ~ LT1's operate when warmed up with the oil pressure on the low side of the gage and closer to the white dot closest to the red indicator. As long as your pressure is there you are in the operating zone. When the engine is cold it will often start out much higher only to settle back down when the oil gets hot. There are so many variables like: Newness of the bearings, srring tension, clearances, oil viscosity, and the pump itself that affect the pressue. These levels are from my experience using multi-viscosity synthetic oil. 
I'd look very closely at your PCV system, I bet thats what is causing the leaks from excessive crankcase pressure. I had bad oil leaks from the front and rear seals...and when I did my engine bay clean up, I eliminated the PCV system all together and used a breather in each valve cover. Mysteriously, all the leaks stopped. Coincidence? You decide.
FWIW, I think the stock PCV system works fine on a stock internal engine. But I feel on a highly modded motor, the added pressure is more than the stock system can handle. Thats when it's time to find a more effective method of relieving crankcase pressure. The easiest is to simply put a breather in each valve cover, but there are other options as well...
FWIW, I think the stock PCV system works fine on a stock internal engine. But I feel on a highly modded motor, the added pressure is more than the stock system can handle. Thats when it's time to find a more effective method of relieving crankcase pressure. The easiest is to simply put a breather in each valve cover, but there are other options as well...
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I'd look very closely at your PCV system, I bet thats what is causing the leaks from excessive crankcase pressure. I had bad oil leaks from the front and rear seals...and when I did my engine bay clean up, I eliminated the PCV system all together and used a breather in each valve cover. Mysteriously, all the leaks stopped. Coincidence? You decide.
FWIW, I think the stock PCV system works fine on a stock internal engine. But I feel on a highly modded motor, the added pressure is more than the stock system can handle. Thats when it's time to find a more effective method of relieving crankcase pressure. The easiest is to simply put a breather in each valve cover, but there are other options as well...
FWIW, I think the stock PCV system works fine on a stock internal engine. But I feel on a highly modded motor, the added pressure is more than the stock system can handle. Thats when it's time to find a more effective method of relieving crankcase pressure. The easiest is to simply put a breather in each valve cover, but there are other options as well...
Now, just to clarify, what are you guys talking about when you say PCV system? I've always thought the system was the PCV valve in the driver side of the intake with a hose that goes to the front of the intake. I still have that there with a catch can ran in the mix.
http://shbox.com/1/pcv_pipe.jpg
Now I took off the breather looking thing on the passenger side that had a hose running to the TB and replaced that with a breather. Then I plugged the TB port.
Oil pressure is high when it's just started, but goes down after it's warmed up. But at WOT it is pretty high. I run 5w30 also.
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I have been reading and could it be possible that something wasn't done right with the rings and I am just getting really bad blow by?
EDIT: Nm, I just checked the specs on the rings and if they were installed like they wrote down then they are fine.
EDIT: Nm, I just checked the specs on the rings and if they were installed like they wrote down then they are fine.
The CCV hose that you replaced with a breather is part of the PCV system. With it hooked up as the factory installed it, it is the fresh air source, which makes it a closed PCV system. If you removed it, the PCV system no longer functions as intended anyways...and even so, one tiny breather is likely not enough to vent the pressure your big 383 produces.
With that said, my advice based on personal experience is to remove the rest of you PCV system and use a breather on each valve cover. If you still want ot run a catch can, switch to a vented catch can and run a hose from each valve cover over to the catch can. This is essentialy the same as running a breather on each valve cover, but will catch the excess oil vapor rather than making a mess on your valve covers.
Or if you really wanna get into crankcase evac systems, you could research electric and mechanical vacuum pumps, or even a header evac system. Breathers are without a doubt the easiest, and cheapest way to go.
I know not everyone agrees with me on this subject, so be sure to do your research on your options and not just take my word for it. There are alot of guys that swear by the factory PCV system, but I have yet to see it function properly on a highly modded motor even when all the componets are brand new. Thats why my opinion is what it is.
With that said, my advice based on personal experience is to remove the rest of you PCV system and use a breather on each valve cover. If you still want ot run a catch can, switch to a vented catch can and run a hose from each valve cover over to the catch can. This is essentialy the same as running a breather on each valve cover, but will catch the excess oil vapor rather than making a mess on your valve covers.
Or if you really wanna get into crankcase evac systems, you could research electric and mechanical vacuum pumps, or even a header evac system. Breathers are without a doubt the easiest, and cheapest way to go.
I know not everyone agrees with me on this subject, so be sure to do your research on your options and not just take my word for it. There are alot of guys that swear by the factory PCV system, but I have yet to see it function properly on a highly modded motor even when all the componets are brand new. Thats why my opinion is what it is.
Last edited by Colin91Z; Mar 20, 2010 at 10:58 PM.
If you are getting positive pressure through your seals with a breather on your valve cover you have more serious issues. If you think you have abnormal blowby then get a leakdown down and see. The stock PCV system is plenty to handle normal blowby of most any application on the LT1.
Last edited by SS RRR; Mar 21, 2010 at 11:08 AM.
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Joined: Sep 2006
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From: Savannah,Ga.
could be bad ring seal..i saw in an earlier post that you have a breather on the valve cover..do you have a lot of vapors coming out of it at idle(when hot)??did u check for vacuum at the pvc valve?how did u break the new motor in?