crazy97

iTrader: (1)

I have not taken the front off, I never found a reason to till now. I definitely catch oil in my catch can. Im not sure if it all goes through there, but I have found puddles of oil in the plenum... And I only lose about a quart every 1500 or so.

P. Samson

You are reading way too much into the oil that is sitting in the head area of the camshafts etc. There will always be some oil that puddles there. It is draining down into the sump just fine when the engine is running or there would be a helluva lot more than that there. In other words your head drains are not obstructed/plugged. The oil that you find in your catch can (if you have one), in the crankcase vent/blowby hose/s, the PCV valve and hose, and the intake plenum are condensed oily breather vapors. It's normal. The amount of breather vapors is a function of the condition of piston rings/cylinder bores, how often that you romp on it, and there tends to be more with a manual tranny. The VQ35 also has oil jet piston squirters which may explain to some degree why the VQ35 has more of an issue with HOC than the VQ30. The piston squirters have got to be adding more atomized oil into the breather vapors.

Ghost_54

iTrader: (13)

Would not a reasonable amount of oil residue be considered normal and wanted? To me one would want to have this residue as in the picture to help prevent what I have always know it as "Dry Start" where you would get metal to metal which would increase the metal scoring within the engine. So for me seeing some oil residue as pictured above along the cams would be a good thing especially after many hours of sitting, to prevent Dry Start.

P. Samson

As I mentioned there is always going to be "residual" oil that is left/puddled in the nooks and crannies of the head areas as seen in the above photo. After engine shutdown even when most of the oil has drained back to the sump, oil (at least a thin coating) is always going to be left on any oil wetted parts and areas of an engine......it just doesn't drip off completely......that's one of the important properties of motor oil, and this is what does give the critical parts the wear protection during engine start until more oil is delivered as the oil pressure builds.

NismoAce

iTrader: (6)

I agree that remaining oil is a good thing. I am not asking for a dry valve train. I am asking for there to appear to similarities between the two heads. With both covers off there is a easy to tell difference. The front has a nice coat preventing dry start and the rear has pools in it. Leading me to believe there is a blockage preventing a quick drain of any pools. if there is even the slightest blockage compared to when it left the factory the oil may not drain as fast as the oil gets put up there. This would be like have a bath tub filling up faster then the drain can drain. you will end up with a full or over flowing tub eventually. I think in the rear head it is just enough to saturate the valve cover to the point that the pcv can no longer do its job because it can only suck up oil just like a straw. I think if you drive normal this may not be an issue but a spirited driver such as myself may see this more often. I want my car to run to full potential all the time as much as it can.

Update. 150 miles since the mod and still not a single drop of oil in my catch but I am collected a fluid. It like water with a gas smell. So the pcv is infact doing its job. I check my dip stick and I am still 100 percent on the full notch. I check my oil at the same location all the time and over night after it has had plenty of time to settle. I am excited to say I think this is a win but I will not call it till about 1000 miles or even a full oil change. I normally put in a quart every 400 miles. So by now I would have noticed a dip in oil. If I can go to the next oil change and still look this good I will do the happy dance on top of my car. I will continue with updates.

TunerMaxima3000

iTrader: (4)

This is NOT helping your oil burning issue. Idling your engine like that will cause oil burning by wearing out rings and many other components much faster than normal.
You don't need to 'warm' your engine up, it's not a 1960's carburated (sp) engine. Just drive it a bit easier until the engine reaches operating temperature.

Not trying to bash you or anything, I just found it ironic that you're battling oil burn so furiously, and then you're idling the living crap out of your car, defeating the purpose completely. I'd also assume that is why you had SO MUCH oil in there in the first place (not to say that there aren't other issues at work such as the ones you're combating, just seems like more than normal by comparison).

I applaud your efforts here, I'm glad that you've found somewhat of a solution to a common problem with the VQ35, but I'm somewhat confused... I always thought the main cause Nissan eluded to was poor ring design?

Either way, I'm good, DE-K FTW

This is correct. You want oil to sit up there. To the OP: you can't expect the amount of oil in the front bank head to be the same as the rear bank, they never will be, especially due to the FWD designation (engine sideways). Take into account Gravity, slope, braking, acceleration, + all the dynamics of oil distribution flow through the engine. You don't want one dry and one soaked though, that would indicate a problem.

crazy97

iTrader: (1)

A wet valve train is very good. I tend to agree the pcv is acting like a straw, but in these cars I think the straw is a little low. Stuff splashes around and gets sucked out of the engine. I think if the valve cover was a little higher, we wouldnt be having this problem.

Love the good updates so far!

NismoAce

iTrader: (6)

I agree with you guys especially the fact that if the valve cover was higher we may not experience this issue or not as much. I wish I took pictures of the amount of oil in the rear compared to the front. It was obvious it is a drainage issue assied from the fwd theory. I understand what your saying. but it isnt the culprit in this case. Even after leaving the car not running for 24 hours and taking off the valve covers like I did it was still havilly saturated in the rear compared to the front. I dont agree that idling that long is bad for the engine and will lead to oil burning at all. Makes no sense why I can idle a car but I can cruise on the highway at 2500 rpm. Leather is cold in the winter. I am not getting into a cold car at all. I am not saying you cant be right about doing damage to an engine from letting her idle for 15 min but if you can find proof im down to look at it.

Any of you guys can tell me why it is that I have no sucked up any oil by flipping the routing of the pcv if the only difference is that the last valve cover in flow is the front one?

This is a healthy discussion and if I over looked something or my theory makes no sense I wanna know and I wanna fight this till none of us have an issue any longer..

I have heard by many people and dealerships that the rings are the culprit for oil consumption. I think this case may be out there but a good amount or a small amount of these may just get the oh its rings treatment rather then checking to see if it is an issue such as stated above.

nissan will never admit is a clog by design because if they did they would have to start recalling. if they claim rings they can claim normal wear and tear on it and wipe there hands clean. Car companies are grimey and I wouldnt put it past them if they already know this is an issue. So if you guys never hear from me again I was probably killed by nissan hit men and I think someone should take this into a secret lab and continue my research.

some times I would prefer the 5th gen engine but I love my power.

Wich reminds me. I have a smoother accell. It appears as the engine is relearning some things. It is very obvious to me that there is less crap if none getting into the intake mani. Im sure if oil was getting in the ecu was prob sending more fuel to burn everything off.

crazy97

iTrader: (1)

What size hoses did you need for the full conversion? I know some are 3/8.. I could check but its easier to ask!

NismoAce

iTrader: (6)

Dont even get me started on the hose sizes lol it was a mess. There are 3 diff sizes. I will be getting exact numbers and stuff when I confirm it works. There will be reducers needed. 3/8 covers only the output on the rear valve cover and input on the intake mani if my memory is correct.

btw I take it similar results can be had by caping off the intake manu input and the output by the maf and putting breathers on the block. I dont like the idea and I still see oil coming out of the rear breather if my theory is correct and positive crank case ventilation is a good thing and thats why I chose to maintain the system with modification to its flow.

Thank you crazy for the pic




Its hard to tell from this angle but see where circled how much oil is in a pool there. Well u can kind of see if. if you seen it in person this would remind you of the amount. It is obvious that poor design or blockage is an issue. mine was like that after 24 hours of not running and the front had nothing like it at alllll..

P. Samson

Yes, don't expect the heads and the oil puddling to be exactly the same. The heads are not a mirror image of each other. The FSM does show THREE drains on the low side of each head. If you have no wear issues/noisy lifters etc. then I'm sure that your "drier looking" front head is actually getting enough oil. Normally, the PCV valve should only be flowing breather/crankcase vapors......not gulping oil. The infamous VQ35 oil consumption issue that Nissan finally dealt with was supposedly related to oil getting "sucked" by the piston rings (flutter) during high RPM closed throttle (high vacuum) operation. Supposedly this was caused by less than a perfect piston ring design. I have a buddy that from new owned an '06 350Z 6sp where it took multiple attempts including a new short block (did squat??) and finally a new long block before the oil consumption was more reasonable. That oil that you've circled is perfectly normal.....it's not going to get to a drain hole until it "overflows" from that "puddle/pocket" as it fills up higher than that level during engine operation. I find it difficult to see how your front head looks that much different? There should be pockets of oil just as in the rear.

NismoAce

iTrader: (6)

If a long block was the cure and a short block wasnt, wouldnt that indicate an issue with heads? And I never thought my front head is starving at all. I think the rear is getting too saturated. If the drains are where it sounds like you are saying then I would claim a blockage of some sort.

Ypu are right normally a pcv would only taking in vapors and air but if the oil gets up to the mouth of the pcv then it only has one thing to suck up. OIL.

crazy97

iTrader: (1)

Yep, thats why I asked.

NismoAce

iTrader: (6)

lol


Thank you guys for the healthy discussion.

crazy97

iTrader: (1)

It has to be a drain issue because the 04+ valve covers are exactly the same thus leading me to believe the drains were changed or improved for 04...

TunerMaxima3000

iTrader: (4)

I'll be nice.
Some things to consider.

1. Oil pump is less efficient at idle
2. Your cooling system has to work harder to hold the proper temperature.
3. Idling burns more fuel than highway driving (plus you're not getting anywhere while you're burning it)
4. Read your owners manual. You'll notice 'Extended Idle times' will increase your maintenance schedule, High idle time is considered 'Extreme Conditions' more-so than driving in gravel pit territory is.
5. Fuel doesn't fully burn off at idle, this can cause 'fuel wash' in the cylinders, which not only contaminates the oil, but REMOVES it from the cylinder wall and rings. (not a good thing)

I found a good snippet that relates to this discussion:

Idling, even with a well tuned, and precise fuel injected engine, you don’t burn all of the fuel in the cylinders.
This is why we have EGR, and catalytic systems. Extended idling will cause the unburnt fuel to wash the oil from cylinders, and dilutes oil. The unburnt fuel will also cause carbon deposits on valves, in the EGR system, and cause the catalytic converter(s) to work harder, meaning shortened life.

I could go on for a long time. I hope I don't need to. It's common knowledge that idling is bad for your engine, not to mention your pocket book and mother nature, some research would help you immensely if you still feel it doesn't hurt your engine.

Hope that helps.

^^ Hahaha, yeah you're going to get sniped man watch your back!

NismoAce

iTrader: (6)

agreed


Thank you. Makes sense but it also makes sense to warm up the engine to normal operating temp before taking off for my drive. Of course you should reconsider your normal maint sched if idling is a normal thing because we clock in miles and not hours. Either way I suck up massive amounts of oil on a trip to ny and back. 200 or so round trip. So there is still an issue. And with my remote starting under this mod I have no eaten any oil at all. The beating on the engine and other things can be another fight. Right now this fight is about my straw in oil theory.

TunerMaxima3000

iTrader: (4)

Thanks for this post.

That amount of oil is very normal, if anything, it'll less oil than normal. There isn't a 'pumped' return, it's just gravity fed through 3 fairly large holes in the block.

NismoAce

iTrader: (6)

I am curious to where these holes are and I know its gravity but if there is a clog gravity wont pwn it.

MONTE 01&97 SE

iTrader: (1)

Yes the 06 350's with the VQ35 "rev up" engine are notoriously known for having a major oil consumption issue/problem, it is the year to avoid if you are in the Market for a 350Z. 07/08 HR preferred....hehe

P. Samson

I believe the first short block still had the "old design" rings and Nissan was still fighting this problem at that time. Many months later he got the new engine with supposedly the new ring design, that seemed to have been the fix. If it was a systemic head drain issue on the VQ35 then more of these cars would have the issue that you think you may have.....but the reality is that most of these cars do not have an oil drainage problem. I repeat......the THREE drain holes are about equally spaced on the "low side" (obviously) of each head. I've removed rocker arm/camshaft covers off quite a few cars and actually the head in the photo actually looks relatively dry and "puddleless" compared to some. Some engines only have two drains.

NismoAce

iTrader: (6)

I hear you but it still doesnt make sense why my testing is proving that the rear head gets more flooded during operation then the front head (puddling asside). I am not trying to be convincing here. I think im on to something and if it works for me then it works for me. I am sharing my thoughts and testing here. I appreciate the critism on my theory. If the they are evenly spaced on the low side then we shouldnt have an issue unless there is a slight blockage or the thing wasnt designed correctly for the amount of oil in there to drain properly.

anybody for a pic or a diagram to exactly pin point the oil galley drain? If I had a spare engine and or car I would tear this thing up and study the hell out of it and I bet there would be a difference between an oil galley passage on the engines with known issues versus the ones that have been known to be fine. Nissan could have done some crazy ish at the factory. For all we know some engine might have had certain parts made at a different plant. We are not in control so we dont know.

TunerMaxima3000

iTrader: (4)

NismoAce

iTrader: (6)

Thank u. Looked at that in the fsm. I am more interested in a birds eye view of the rear specifically. Both would be nice with a pin point as to where the drain is. This sorta tells u where but its simply a drawing. I want an actual pic if possible.

crazy97

iTrader: (1)

Any updates?

NismoAce

iTrader: (6)

Havent checked oil. Still sick And when I get out the car I run from the cold. The car has started hesitating again as it does on and off. Hopefully new coils plugs and cattman headers will fix it when they all arrive. will update my oil level.

Gizm0

iTrader: (1)

On the rear valve cover, it should be possible to switch the PCV with the inlet (which is located higher) so that gas and fumes would be sucked out of the VC instead of oil? This way you wouldn’t have to have so many hoses going around in your engine bay?

OnOiShNo0dl3Z

iTrader: (2)

If I lived near you, I'd come over after I get home to drive a couple hundred miles a day and do all the checks haha. man can't wait for results, get well soon.

sc0tty8

iTrader: (1)

In cuz I'm interested.

OnOiShNo0dl3Z

iTrader: (2)

Any updates on how its going?

NismoAce

iTrader: (6)

Sorry guys. I will update as soon as I can.

crazy97

iTrader: (1)

Any luck on this yet?

hacim105

iTrader: (6)

subscribing to the thread.

djshwini

iTrader: (1)

+1.
I love the max, I just want to love her more... After this is fixed.

crazy97

iTrader: (1)

Has the thread died?

hacim105

iTrader: (6)

Would you be willing to post up your current setup (parts list). perhaps someone who is on here more frequently or who has more time can put the parts in and follow up on your testing. I drive 300 miles a week for work so within a couple weeks I could have a good idea if this is really a fix. It already seems like it is from what you've posted up to this point.

cil1jtr02max

iTrader: (1)

Interested in a parts list as well. I think my car's starting to burn oil... I'm going to run out and install a catch-can this weekend.

NismoAce

iTrader: (6)

I would say go with the catch can for now. I am not sure if this mod had anything to do with it or if it was my time but my engine is officially blown. The piston rings are friend and most likely was always the cause of my oil consumption. It happened then got worse and worse till she was smoking but still driving fine then by the time I got back home she barely holds an idle. Now she can barely get up a hill. Looking for a new engine for now the car is parked awaiting that. She also threw up on the ground. puddle of oil. I suspect the worse since a bunch of my plugs are coated in oil as well.

I dont think this was due to my mod unless there ended up being a blockage in one of my lines. There was still ventilation allowed. I think the blow by got the best of everything. I cant confirm this mod had nothing to do with it so I will not recommend it to anyone. I will be looking for an 04 05 engine and pray to god I can find one out of a 6 speed.

crazy97

iTrader: (1)

Holy crap. Sorry to hear that. I had high hopes for this problem.

OnOiShNo0dl3Z

iTrader: (2)

Sorry to hear about your issue. Hopefully, your idea didn't contribute to the issue, but we'll probably never know. Good luck with looking for an engine man.