Excessive Oil Consumption Gen 5 3S-GTE

[RedCelicaTRD]

Ok, had to go look at some schematics and get my brain to stop thinking about 1st and 2nd gen. No PCV on the early gens and there was just a small hose connected to the valve cover and then the throttle body. I'll try and actually read next time and not quickly comment while at work.

The PCV will act as a check valve under boost. However, it will not seal well and you will get leaking. Shouldn't be enough to cause problems, but they never seal 100%. The original PCV on your 5th gen should handle the low speed/load. Then the intake connected ports should take over at higher load. The breather box is an air/oil separator, and like you mentioned should help filter out any oil vapors and condense them back towards the engine. They just have a bunch of material inside to give the vapors something to catch on to. The return line can become clogged on those and lead to oil getting into the intake. I want to say that was considered a service item and should be replaced every 60k miles. Don't remember 100% on that. Some people just clean them out with brake clean.

Pic 3 should be the idle speed controller. If it's leaking under boost it's broke. It should be re-routed to the intake. However, the quick and lazy thing to do is put a breather filter on there. Mine is currently setup the same way...

In your previous post with pictures, the amount of oil you can feel is totally normal. One thing to remember is the oil separator will never get all the oil vapor out before it gets to the intake, and also that the turbo seals are meant to keep air out of the turbo and not oil in. A small amount of oil out of the turbo is expected. I don't find what you found to be alarming.

You mentioned you mainly notice smoke on decal, correct? This is either a valve steam issue or a turbine side turbo issue. There is a product called AT-205 that might be able to help rejuvenate the seals if it's the valve stems.

Did you have this same smoke issue before the turbo swap?

 

[Monachopsis]

Time for me to chime in finally. I have been helping through text long enough! So heres my 2 cents; still havent taken Fluids yet but I have some ok ideas with fundamentals.

Heres the fundamentals without equation. Higher velocity leads to less pressure in the system. Flow rate is area and velocity. Alongside this a larger pipe or tube resists flow more thus leading to slower velocity. Since fluid can only move so much through a given area there are typically 2 pipes in modern engines (gen II just meets in the middle I assume)

By that meaning, my recommendation is to keep all pipe diameters what they are factory and replace them as the PCV system is engineered to have the engine idle and run smooth. Another issue does arise though. When adding a catch can you increase the pressure in the system momentary which could effect the overall system. Since the wagner unit is adjustable, using it in place of the OEM pcv valve with a catch can would probably yield factory like results with extra filtration with the correct tuning of that valve. On the back end, the valve cover, routing those straight to the intake would be best. For the larger diameter line, if you really want to optimize, a smaller diameter could help as you are increasing the amount of line thus generating flow rate loss which can be remedied by increasing pressure differential. (Basically making the air get pulled into it increasing avg. velocity) Yet again a catch can can be 'y-ed' into from the valve cover sections to the intake tube. I would go with a pretty small unit here as it shouldn't be scavenging as much oil as the main PCV under boost.

If you want to go with my idea or a version of it feel free to post the pic i sent over, I can also forward a higher fidelity one too.

 

[Roreri]

Ok, ...

I did have the same smoke issue before the turbo swap. It largely went away after the swap but it's still there. It is on acceleration. I was noticing it after engine braking because I was getting back on throttle as necessary.

Thank you for the break down on the system. Since that second vacuum line off of the throttle body opposite the timing belt is the idle speed controller, I'm not going to route anything to it. I'll put the filter back on it.

The breather box is flowing well. I cleaned it out with warm water and degreaser. The return line for oil to drop back into the crankcase is unobstructed.

It sounds like I have been chasing this around and not coming to the valve stem seals being the issue because of compression being in spec and identical cylinder to cylinder. My logic was that if the valve stem seals were compromised they would not all be equally compromised. Since all cylinders were reading 135psi (at 7200 feet, that converts to 168psi at sea level) in our compression test I felt like all was well. If one or all were low, I'd have gone forward into trying a little oil in the low cylinder and seeing if psi hopped up a bit. If yes, piston ring, if no, valve stem seal.

I had tried some engine oil stop leak but it hasn't corrected the situation. But perhaps it has mitigated it somewhat. I have some AT-205 Re-Seal on hand. Just put it in the engine oil, correct?

Working with Monachopsis, what it looks like the right thing to do is this:

1. Fabricate an adapter with an incorporated baffle so that the M/E Wagner PCV valve can be used in place of the oem PCV valve.

2. Replace the oem PCV valve with the M/E Wagner PCV valve. Tune it.

3. Set up the Saikou Michi Catch can on the PCV valve side of the engine compartment (no ABS so there is a handy spot for this) and route the M/E Wagner PCV valve to it with narrow ID PCV hose, then to the intake manifold.

4. Route the valve cover breather ports as per oem to the breather box air/oil separator and have that return line put condensed oil back into the system. Route the output to the air intake pipe as I have it already. Apply FIPG to the large port so as to provide some seepage prevention.

5. Put that breather filter back on the idle speed controller vacuum line. It drawing engine compartment air isn't a big deal to me.

I have got the system put back together. I have run some engine cleaner through the motor and have dropped the motor oil preparatory to dropping the oil pan. Once I inspect the oil pan and confirm that the turbo return line is clear I’ll refill with oil and add AT-205 Re-Seal.

 

[RedCelicaTRD]

You wouldn’t catch bad valve stems seals on a compression test. The valve is closed during the test, and the stem seal prevents oil from getting into the intake or exhaust port. If the intake is leaking you should notice fouled spark plugs. On the exhaust seals, you’ll get smoke on decel from oil getting sucked into the exhaust port and burning off in the exhaust.

 

[Roreri]

You wouldn’t catch bad valve stems seals on a compression test. The valve is closed during the test, and the stem seal prevents oil from getting into the intake or exhaust port. If the intake is leaking you should notice fouled spark plugs. On the exhaust seals, you’ll get smoke on decel from oil getting sucked into the exhaust port and burning off in the exhaust.

Thanks! The spark plugs were definitely fouled, so that's more evidence for valve stem seals.

Well, if I still have the smoke after all this and after giving the AT-205 a good chance to work, I will take it in for a valve job.

Might have the valves and any other convenient components upgraded/updated while the tech is in there.

 

[RedCelicaTRD]

You can do the seals with the head still on. Cams, cam gears, and springs have to come out. Those can all be upgraded.

The AT-205 is pretty good stuff. Hopefully it works out and points you in a positive direction for repairs.

 

[Roreri]

You can do the seals with the head still on. Cams, cam gears, and springs have to come out. Those can all be upgraded.

The AT-205 is pretty good stuff. Hopefully it works out and points you in a positive direction for repairs.

Maybe I’m just poking around at this point trying to avoid the inevitable.

I’m dropping the oil pan today and seeing what’s going on with that, and ruling out the turbo oil return path being blocked. I’ll add new oil and add AT-205 Re-Seal to it and see how that works, before I gird my loins for the next step.

Have you done the valve stem seals with the head in it? Like you said the parts have to come out of the way to get to them. Then. I understand there’s a specific way to do it: Cylinder to TDC, rope or air compressor to compress the valve spring, then a specialty tool from Toyotool.

If I do this or have it done do you think it a good idea to just replace the valves and valve guides?

Any recommendations on parts?

There is a good tech here in town that could do this for me but like all good techs he’s so good he’s too booked and not terribly interested in being more booked.

 

[RedCelicaTRD]

The worst part of doing the valve seals with the head on is the usual lack of clearance. It seems like the removal tools always need a lot of room, which we don't have. The tools might hit on the intake manifold making it a bit annoying.

On a Toyota, the valves and guides usually stay true for a long time unless they somehow get bent. If you wanted to have a head built, sure put new ones in. If you just want to get the smoking to stop I wouldn't worry. My main concern is always the head gasket sealing and that is why I would consider doing it with the head on. Then you also don't need to take apart the cooling system to get the head off.

The 2JZ has an almost identical setup to the 3s for valves. If I remember right the valve seals are the same part number, but I would need to double check. I think this video from Speed Academy does a good job of showing what tools to use and how easy the job can be in a non-cramped location.

Since you could use the leak down tester to verify blow by before digging into the head, it wouldn't be a bad idea to pick one up and do some initial testing. Then if it's still looking like valve seals you can use it to hold the valves in place. I've used rope before and it does work. And you don't have to worry about air compressor issues causing a valve to slide down. Air is just less time consuming in my opinion. Don't have to put rope in, turn the motor, hope you're not putting dirt in the cylinder.

As for performance parts, are you still MAP sensor based with the OE 5th gen ecu? I'd be getting nervous that the new turbo could flow a bit more then the ecu is expecting if you were to install things like bigger cams.

 

[Roreri]

The worst part of doing the valve seals with the head on is the usual lack of clearance. It seems like the removal tools always need a lot of room, which we don't have. The tools might hit on the intake manifold making it a bit annoying.

On a Toyota, the valves and guides usually stay true for a long time unless they somehow get bent. If you wanted to have a head built, sure put new ones in. If you just want to get the smoking to stop I wouldn't worry. My main concern is always the head gasket sealing and that is why I would consider doing it with the head on. Then you also don't need to take apart the cooling system to get the head off.

The 2JZ has an almost identical setup to the 3s for valves. If I remember right the valve seals are the same part number, but I would need to double check. I think this video from Speed Academy does a good job of showing what tools to use and how easy the job can be in a non-cramped location.

Since you could use the leak down tester to verify blow by before digging into the head, it wouldn't be a bad idea to pick one up and do some initial testing. Then if it's still looking like valve seals you can use it to hold the valves in place. I've used rope before and it does work. And you don't have to worry about air compressor issues causing a valve to slide down. Air is just less time consuming in my opinion. Don't have to put rope in, turn the motor, hope you're not putting dirt in the cylinder.

As for performance parts, are you still MAP sensor based with the OE 5th gen ecu? I'd be getting nervous that the new turbo could flow a bit more then the ecu is expecting if you were to install things like bigger cams.

The 5th Gen is MAP sensor based, I am morally certain. TCS didn't install a standalone ECU, just an electronic boost controller.

Different thread describes the How I Got a Sweet 16 Turbo for Roreri. After installing it, I had the solenoid set for very low duty cycle and just did 30 miles of low boost check ride under 7psi max. The next day, over the course of 500 miles and a day of driving, I increased the duty cycle and watched boost and AFR on my standalone AFR gauge. I get a bit of boost surge that shows up as oscillation at the top end if I don't hook into it right. But if I do hook into it right--it's a matter of foot technique on the fun pedal--then it's stable up to 15psi.

It's a good idea to get a good leak down tester. I can put off the inevitable for a while longer and satisfy my insatiable craving for knowledge. I'm just a little uncertain about doing the valve seals. There's a line beyond which I don't feel comfortable going. But depending on conditions, I could be persuaded. It wasn't a lot of fun pulling the valve cover but with Monachopsis keeping me company we did it. I've grown a lot with this car.

I dropped the oil pan. The bolts were no problem. I had sprayed the ones I could get to with pen oil but they came out the same as the ones that I hadn't sprayed. The gasket was a bit of a pain but I got a thin putty knife in there and once I did I just sliced around the edge and pulled it off. The gasket material was something other than FIPG unless FIPG turns gray over time or heat or whatever. I gave the whole pan a good cleaning and degreasing, then took a deadblow hammer to the dent to knock it back out a bit, then primed it and painted it cold iron to break up the unrelenting black that characterizes the engine in general.

The channel for the turbo oil return is clear. It is just a hole in the block. So it isn't oil backing up into the turbo and then being forced out into the turbine side or downpipe side.

Reinstall was simple. Degreased and cleaned all surfaces repeatedly. FIPG around the perimeter surface, lift it up and secure it with bolts, hand tightening then cross tightening lightly.

I put a new oil filled oil filter on but I am waiting a day or two to let the FIPG set before loading it with oil and AT-205.

I took a couple of pictures of the Gen 5 oil pan internals. It's pretty simple stuff. A draw tube and solids separator descends quite a bit below the farthest point the dipstick intrudes into the lower sump space. A baffle reduces wave action around the dipstick. Maybe. I found a couple of disturbing bits of something (hardened old FIPG?) in the separator. I think that light colored oil pan looks nice.

 

[Monachopsis]

Cams will need a tune for sure. You could do arp bolts and personally maybe a hks timing gear. Like we talked about Tony wouldn't mind doing the job if it persists.

If you do go through with it new valve buckets would be nice (toyota tick is caused by them typically).

I still doubt the stem seals are leaky though as like Tony remarked, bad seals would constantly smoke.

 

[Roreri]

Cams will need a tune for sure. You could do arp bolts and personally maybe a hks timing gear. Like we talked about Tony wouldn't mind doing the job if it persists.

If you do go through with it new valve buckets would be nice (toyota tick is caused by them typically).

I still doubt the stem seals are leaky though as like Tony remarked, bad seals would constantly smoke.

I have some small doubt that the valve seals are the problem too. Maybe it’s just hope. But like Tony said bad seals would constantly smoke.

But we’re rapidly running out of causes. The fact that the dipstick stayed in battery over the 90-mile Pikes Peak climb was a hopeful sign that perhaps that new PCV grommet and routing the valve cover breather through the air/oil separator to the air intake has relieved crankcase pressure sufficiently to change things.

If smoke and oil consumption persists after trying the AT-205 and the M/E Wagner PCV with catch can, there’s not much else to try other than valve seals.

 

[scandinavian link]

I feel like I remember valve stem seals being an issue on the 5S-FE engines in the 90's GT & GT-S Celicas, and generally they did just do a puff of smoke on startup (unless they got really bad I suppose). I think I had it on my 90 GT...didn't burn A LOT from it though, just what managed to soak through while sitting. Memory is fuzzy though. Eventually had them done when I replaced the head gasket with a MHG thinking I was going to turbo the 5S (never happened).

Maybe completely unrelated here though.

 

[Roreri]

I feel like I remember valve stem seals being an issue on the 5S-FE engines in the 90's GT & GT-S Celicas, and generally they did just do a puff of smoke on startup (unless they got really bad I suppose). I think I had it on my 90 GT...didn't burn A LOT from it though, just what managed to soak through while sitting. Memory is fuzzy though. Eventually had them done when I replaced the head gasket with a MHG thinking I was going to turbo the 5S (never happened).

Maybe completely unrelated here though.

Aaron Bunch of ATS said that his experience with MR2s led him to believe that MR2 meant "Leaks oil."

 

[Monachopsis]

Aaron Bunch of ATS said that his experience with MR2s led him to believe that MR2 meant "Leaks oil."

This is so weird as my gt4 is like notoriously unleaky. My tc burns and leaks like a mf.

 

[scandinavian link]

Aaron Bunch of ATS said that his experience with MR2s led him to believe that MR2 meant "Leaks oil."

Haha, come to think of it, it may have been the 5s-fe in my ‘91 MR2 with the valve stem issue...pretty much all those early 5s-fe engines I suppose.

 

[RedCelicaTRD]

Vavle seals will slowly progress to causing smoking all of the time. A seal doesn't go from good to 100% dead overnight. For the intake path, we all know when you let off the throttle you create vacuum in the intake manifold and valve area. If the seals are starting to fail and have become hard they no longer seal well enough to prevent that vacuum from drawing in oil from the valve cover. This doesn't mean that they will have failed enough to prevent oil from getting into the intake during cruise ("low" vacuum) or under boost. Under boost it should be pushing oil away from the valve if they have failed completely. Obviously I don't know if this is 100% your problem, but based on what you've described it's where I would start looking.

And buying tools to test stuff is always fun!

 

[underscore]

Haha, come to think of it, it may have been the 5s-fe in my ‘91 MR2 with the valve stem issue...pretty much all those early 5s-fe engines I suppose.

My 184 with the 5S leaked so badly at one point that I needed a top up every day. Luckily my buddy worked at an oil change place that offered free top ups. They started just keeping a jug by the door and running out to top me up without me actually waiting in line and driving in lol.

The RC leaked a lot when I got it. After a lot of time, money, and effort, it leaks a bit less. There's nothing really actively leaking anymore but there's some verrrry slow weeping of the oil and I think trans fluid from somewhere.

 

[Roreri]

Well at least my motor’s leak has been internal. Below the motor it’s dry as a bone.

I added oil and a bottle of AT-205 Re-Seal yesterday at 102,984km on the odometer then idled it for a bit to get the AT-205 through the system. Yes, sigh, that last oil change only lasted 300km and a trip up and down Pikes Peak. But once oil leaves the motor I am loath to put it back in.

Running another engine cleaning through it before dropping the oil so soon might not have been best for the seals as well, because “it is said” that old sludge can reinforce seals a bit and the harsh chemicals in cleaners can weaken seals. So broscience and the cleaner and AT-205 are duking it out within my motor to see who will prevail.

Took it out for a coffee this morning to circulate the AT-205 through the system and wet all the seals. Kept the motor below boost to just check things out. No visible smoke that I was able to notice out the rear or side view mirrors. When I put my nose down to the tailpipe, the exhaust smells sweet of uncatalyzed and unburned gasoline, not oily.

I am going to let the AT-205 work its deal over the next couple of days, keeping the motor below boost and avoiding engine braking and the increased vacuum down to 50cmHG or more that comes with it.

I guess I do want to pull a plug or two and see what’s going on fouling-wise. It’s only been 200 miles since we changed out the plugs so if gross fouling is happening that would be the tell.

Still working on an adapter for the M/E Wagner PCV valve. Things have been popping up so I’ve been distracted. I owe Monachopsis a drawing. I need to get a micrometer because dimensions are a bit unclear.

 

[Roreri]

Monachopsis came over with a 6061 aluminum billet adapter. It was exactly as we wanted—just a tiny bit too large to go into the PCV valve port. Some sandpaper and freezing and warming and in it went with just a light tap of the rubber mallet. Then the valve cover warmed up and swelled the adapter for an interference fit. Then a little FIPG on the M/E Wagner PCV valve to provide positive seal, and in it went. Looks good, though I’ll need to re-orient the PCV valve outlet toward the front of the engine bay when the Saikou Michi catch can arrives.

Also, obligatory two JDM GT-Fours in the same driveway photo.

 

[underscore]