Oil Leak at Oil Cap
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Teching In
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Oil Leak at Oil Cap Well I purchased this car over the past weekend and it has an STS turbo system on it. I saw that a little oil was leaking from a connection where the oill return line goes to the oil cap. Me and my friend re-tapped the oil cap and epoxied it and all and it did not leak. Took it for a drive and got into boost. Came home to see that the pressure pushed the oil cap up a little when in boost and cause for oil to spray out. So I got a new oil cap now and we are going to tap that one and see if it works.
You guys have any ideas or thoughts. I figured you guys may have some experience since I am new to the LS1 motor.
You guys have any ideas or thoughts. I figured you guys may have some experience since I am new to the LS1 motor.
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Teching In
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After doing some research, is it better to just forget this whole concept and tap the oil pan? If so, what is the best way to do it and best tools to do it with? Obviously we dont want metal shavings in the oil pan and what not.
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Teching In
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Any other opinons guys..........
The easiest way to fix that leaking oil cap is to remove the passenger side valve cover ,drill and tap it for a fitting ,clean and reinstall.attach your oil line to the new fitting and you are done .Go back to a regular oil cap.
How would tapping the vavle cover help the oil pressure in the vavle cover. To me all that would solve would be the the location of the oil return line. What is happening is when the car is under boost the pressure in the valve cover has to go somewhere and the plastic cap is the weakest point and then in turn pushes the seating of the cap up just enough to let pressure/oil to start spraying out. This problem seamed evident with the previous owner tryed to fix with siliconing the cap... didn't work to well. If the oil line was to be put in the pan the pressure in the vavle cover to me would still be there. I was thinking about buying a new cap and taking the plastic elbow out and screwing the cap directly into the valve cover and put a longer copper elbow from the line to the cap. On the belief that the cap is warped/elbow.
I have mine going in to the valve cover. After blowing oil all over my engine a couple of times, I was done with that cap that came with the kit. Now, I have a breather where the cap was, and the oil return into the valve cover.
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Do you happen to have any oil blow thru the breather, or is the breahter acting like a vent and not allowing the pressure to build up in the vavle cover? The LS1 vavle cover has a slight contour to it. Do you happen to have any suggestions on where you tapped and what tools you used? Also I am going to try a different method instead of the cap this week some time. If you any pics they would help too.
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Launching!
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i think everyone is ignoring the fact that there shouldnt be that much excess pressure in the valve cover to begin with. Is this a stock bottom end motor? if so, this may be the early warning signs of blowby. Blowby occurs when the ring lands on your pistons crack due to high boost / cylinder pressure. This cracking allows some of that cylinder pressure to pass through the rings and into your crankcase. The crankcase and valve covers experience the same vapor pressures, so if your valve cover is under pressure, then your crankcase is as well. The severity of this issue all depends on how much air flux is occuring past the rings. If your cap is blowing off, i believe its time for a new bottom end. otherwise for your sake, i hope it is a faulty pcv valve... goodluck, i hope this is helpful.
How would tapping the vavle cover help the oil pressure in the vavle cover. To me all that would solve would be the the location of the oil return line. What is happening is when the car is under boost the pressure in the valve cover has to go somewhere and the plastic cap is the weakest point and then in turn pushes the seating of the cap up just enough to let pressure/oil to start spraying out. This problem seamed evident with the previous owner tryed to fix with siliconing the cap... didn't work to well. If the oil line was to be put in the pan the pressure in the vavle cover to me would still be there. I was thinking about buying a new cap and taking the plastic elbow out and screwing the cap directly into the valve cover and put a longer copper elbow from the line to the cap. On the belief that the cap is warped/elbow.
Yes it is a stock bottom end motor, But I was learning that at idle there is a vacaum in the valve cover on a lot of motors and there is on his. The pcv system I do belive is stock, so the PCV valve may be gummed up or not working right. The oil cap it self is not the most secure either, is there supposed to be any kind of pressure in the vavle cover under boost? When doing a vacaum test the motor went from idle @ around 17to20 vacaum to 0 then when reved and held then the pressure fell steadily back around 17to20 which is normal, So I don't think we have a blow by.
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From: Bellevue, Wa
agreed, dont cover up the problem.
pcv is setup wrong or you have worn rings if your blowing the cap off.
if you setup pcv right and dont have worn rings you wont push oil out the cap simple as that.
pcv is setup wrong or you have worn rings if your blowing the cap off.
if you setup pcv right and dont have worn rings you wont push oil out the cap simple as that.