It must have been the O-ring
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To Carl, it is not an exaggerated photo. Just a worst case example. Most will have a smaller gap but it part of the problem. Worse is that even fewer get the brackets to prevent it. And yes this O-ring has destroyed thousands of engines. This leak is the biggest cause of DOD lifter failing. Oil pressure drop when the system tries to go into 4 cylinder mode is the cause. Not enough oil to collapse the lifter. Many do not under stand the system applies oil pressure to the lifter to make them collapse. Not release pressure then they collapse. You can see on Danv508 photos where the pick-up tube was tight on one side of the pump body, and the other side was not. Proof it was lifted some.
And for the comment above. Yes all LS engines are just iron and aluminium parts. That’s the beauty, once you put a cam in one it is transformed. How many times has Richard Holdener taken a junkyard motor and made 400 to 500+ hp by just swapping the cam.
Ok, who wants the soap box next?
And for the comment above. Yes all LS engines are just iron and aluminium parts. That’s the beauty, once you put a cam in one it is transformed. How many times has Richard Holdener taken a junkyard motor and made 400 to 500+ hp by just swapping the cam.
Ok, who wants the soap box next?
Thank you for your reply. Once again I will state that I do not do performance enhancers or engine internals. From the beginning I have simply asked how I can have a oil pressure one day and then a few days later it drops right out. I have been inundated with Members telling me to do the lifters and that the cam bearings are toast but my question is in the one that was never answered is how I can have a little pressure one day and not the next. So that is why I have so many posts about this problem I just want to understand all the comments and which direction I wanted to go. I have stated that I just did the oil pump with a high volume high flow pump with the stock spring installed as it comes. The car has now been started six times in allowed to come up to full operating temperature and oil pressure has not gotten anything lower than 38 psi. Even while I was in the middle of this repair I had people telling me that the bearings are toast and the engine is junk But again like a broken record how do I now have perfect oil pressure how did that bearing just decide to reseed itself and hold pressure. I know people keep bringing it up that I mentioned this is a $1500 car and it is it is in great condition with a lot of miles and I do not want to make it a $10,000 car I want to enjoy it and keep it running that’s all. I did listen to all your suggestions and I was just trying to figure out the best course of action and I’m hoping I found it.
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I don't know who Carl is but if you're alluding to me, I need to reiterate that the point I was making was my suspicions with the pickup tube mounting isn't the cause of the oring itself leaking. 100% the oring fails on lots of engines causing engine failure; no doubt there. I was merely positing that maybe it fails due to age and mileage, and sometimes install error/ defects.
Hey, hind sight is 20/20. This whole job could have been under $50 in parts. An O-ring, gaskets, shim for the oil pump. Yes the O ring can leak dues to age only. Those ones drop to around 20 psi. Ones that drop to almost 0. Those have it worse with a gap,or have been ignored for a long time. Either way it happens and a bracket to use the other bolt hole will make any O ring last longer. Or even better use a Better O Ring. Yes there is one. GM is silicone with a red Teflon coating. Last long enough to make it past the warranty. The Felpro one is made from Viton. Same as the valve stem seals.
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2009 PONTIAC G8 6.0L V8 Oil Pump Pickup Tube O-Ring | RockAuto
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I haven't been on the forum in ages but saw the inquiry about oil pressure. Another possibility is that a particle got caught in the bypass valve in the oil pump or the one in the pan. I've seen one get caught in the pump bypass and lose pressure but it stayed in place and had to be fixed. I've not seen an o-ring cause an intermittent problem that then goes away. OP, did you get zero oil pressure and then good or low and then good? I've never used a bracket to add the other side hold down for the pickup tube either and never seen a problem if the o-ring is installed correctly (not pinched or the wrong o-ring).
Yes occasionally it would have OK oil pressure and by that I mean like 20 to 25. But on occasion it would drop down to five psi and lower that’s when the ticking started. Even after I ran 15/40 oil in it it did the same thing but since then which is been over a week after installing the new oil pump oil pressure hot hasn’t gone below 38
Hmmm. One other thing that comes to mind is that there is a screen filter under the oil pressure sensor in the valley cover. I have heard of those getting clogged with sludge on a high mileage engine but haven't seen it myself. It's not the easiest thing to get to as you need to remove the intake manifold to access it. I just pulled one out of a customer car I'm doing a DOD/AFM delete on just to look at it and had to use a right angle pick to pull it out. You have to remove the pressure sensor to get to it. The puzzle would be why it is intermittent but I suppose sludge can move around. You could take it out and have a look and clean it if it's dirty.
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