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I have put a MM catch can on it. Drove the thing on a 10 hour trip Saturday starting about a quart or quart and a half low as mentioned. Got pretty much nothing in the can. The pcv and vent lines did get oil when the tank was full, but cleaned out once it got down that quart and stabilized. I agree, it acts as though it is overfilled when the tank has the full 10 quarts in it, which is why I double checked that I did indeed have the larger '09 tank and not an earlier one. And it does have the right tank. Wish it were that easy, I mean I have another one on the shelf here.
But that also doesn't explain why the tank empties back out into the motor so fast after shutting it off. That perplexes me more than anything (and makes it tough to check the oil level) and I cannot help but think that it's related to causing it to be unhappy when the tank is full.
I've also yanked the cap off the tank when the car is running to see if there was positive pressure there, but there is not.
The pump thing is a good thought. Wish there were a way to check that which doesn't involve putting on a new one.
Any possibility the tank to engine hoses were swapped? Not sure this would explain your symptoms, but there are two different pumps (sump/scavenge and supply) connected to these hoses, so their drain rates may be different.
Keep us updated on your progress, this is indeed a puzzler..........
ive read through the posts and ive come up with a question. why does the engine smoke when the tank is full to 10 quarts but stops after a quart low is found? sound like too much oil. but that's not supposed to be right with an 09 tank. the drain back issue, I called Peterson Fluid Systems, their answer, "I don't know" they specialize in dry sump systems. TO be fair I was asking about this particular situation and not one of their products. The oil pump scavenges the sump, I do know that and that also creates positive drainback from the top of the motor, could this be part of the issue?
ive read through the posts and ive come up with a question. why does the engine smoke when the tank is full to 10 quarts but stops after a quart low is found? sound like too much oil. but that's not supposed to be right with an 09 tank. the drain back issue, I called Peterson Fluid Systems, their answer, "I don't know" they specialize in dry sump systems. TO be fair I was asking about this particular situation and not one of their products. The oil pump scavenges the sump, I do know that and that also creates positive drainback from the top of the motor, could this be part of the issue?
You've hit the nail on the head. I still don't know the answer to the questions. I *am* sure it's an '09 tank. It has the little add on pony tank that the '09 and up has. And I am sure it's never been filled over 10 quarts while I have had it. Two Mobil 1 jugs are right at 10 quarts. And it consistently smokes heavily out the exhaust until it has pushed out about a quart. I say about because it is flowing the oil back so fast that it is hard to know exactly what the oil level truly is. I'm just trying for consistency when I check it and hoping that I'm close.
Once it stops smoking it "seems" to use no oil at all. With the caveat that it's tough to tell.
I'm starting to wonder if there is some sort of issue with the oil flow to and from the little add-on secondary tank that GM added to these. If there is air trapped in there, if it is pressurizing or something. I'm grasping at straws here, I know. I have checked the vent at top that tees into the main vent hose, and it doesn't seem blocked.
I have a second tank on it's way to LPE right now, that I want to try, but I have a question as to whether it'll bolt on easily or not.
FWIW, I do have an MM catch can on here, and there is not much more than a couple of shot glasses full of oil in it between changes, which I don't think is unusual.
Just off the TOMH it's possible that, for some weird reason, you are overfilling. The stick marks are wrong, something in the tank construction went wrong (GM never tell you this), your capacity with the lines & filter & cooler etc is off. Just some guesses. You know when you drain there is still a LOT of oil left that never drains, right? So if you then add 10 you just overfilled, right? Just thoughts, good luck.
I put about 8.5 in then run it a day, check per procedure, add as needed.
See my video, you know the marks on the stick are NOT 1 qt apart, right? I documented in the video.
If I remember right the arrow are 2009 and up. As I recall, the 2008 and older doesn't have the arrow and definitely doesn't have the threaded mounting bosses for the zr1 style water/oil cooler/heater setup.
Much as I love CF, this is not the place IMO to get really good detailed tech info, Unless one of the guys who knows the chit, decides to get on the thread. I think you need to go elsewhere and figure out the fast drain thing and start there.
Wish I could recommend another forum but I don't really have one. CF is like a really big shallow pond, no real depth of info, less like I said, an expert chimes in.
I swapped out the '08 LFE tank for the stock 09 tank today. Filled it to 11 quarts and drove it around the block a little. No smoke. So, that's a step in the right direction. Didn't get it hot enough to check the level. I'll take it for a ride after I get a shower, get it hot, and see what the oil level shows on the stick after 5 minutes or so.
The only other detail I need to check is if the 08 and 09 dip stick are the same part number. Unfortunately all the GM parts websites like Cultrag only show accessories for Corvettes now. Not sure why that is.
Going to have to. Pretty sure that the part # for the older model was superseded by the newer which makes them interchangable, but it would be nice to find out for sure.
And what the hell happened to all the GM parts sites?
Cleared the smoke issue completely when filled to proper capacity. Need to drive it again, get it warned and then see if the oil drains back. I am guessing that it will not do that. Probably be Friday before I get to that.
It will be interesting if the stock tank fixes it.............I switched to the Lingenfelter expanded tank in my 07z as soon as I got it in 2011 and have not had any issues with it.
I'm actually going away from the stock 09 tank to an LFE 08 tank with an Avaiad screen. I had the same setup in my 08 z and it worked fine, I'd imagine that it'll be fine in the 09. At some point I'll open up the original 09 tank and find out why it's been such a pain in the neck, but I don't know how soon that'll be. I'm in no rush now that things at least appear to be settled.
Your issue with drain back has made me wonder so today I opened up a early spare tank to get a better understanding of how it works. I also found a sketch I edited to make it match the pictures. The stock pump picks up oil from the sump and sends it to the top of the tank by tube that is not sealed into the base and it is a fairly loose fit on the bottom. The top does have a gasket but again not very precise. That leaves two paths for the oil to drain back from the tank to the pan. If nothing is broken and all parts are installed the oil is either passing through the pressure side of the pump or from the tube to tank base interface.
I would not expect it to pump and leak back at the rate you are seeing. My first thought is the tube in the tank might be damaged or misplaced. It is not a precise fit and I was a bit surprised that it is not sealed at the tube/tank interface. This is the first system that I have seen that does not check the oil level when running but the tank pressure may be an issue with checking while the engine is running.
01-02-2019, 06:16 PM
