[Serf27]

Originally Posted by arkie6

I'm having a hard time keeping up with what you currently have. Do you have the flapper valve installed? If not, that could mess with the amount of air flowing through the PCV valve into the intake manifold and be seen by the engine as a vacuum leak. The flapper valve has a small hole in to allow a small amount of metered air flow into the engine crankcase during high vacuum conditions (assuming you have either the internal or external PCV valve installed and connected to a source of vacuum). If the flapper valve is absent you could be pulling in so much additional air that the engine is seeing a lean condition.

Yes I still have the flapper valve.

This is what I have.
Flapper valve to catch can to rear inlet
On the PCV side I have the PCV delete fitting followed by external PCV. Ir goes to a catch can then goes to a T fitting on the vacuum line that connects to the throttle body.
I’ve seen other run that set up but now I’m getting fuel mixture codes and I’m not sure if they’re related to the extra vacuum the throttle body line is pulling.

[Moisture]

First, lets try and understand not only what causes excess carbon build-up but ways we can minimize it, if not eliminate its presence all together. Often it is largely a factor of the way the ECU is programmed to inject the fuel into the cylinder.

We know that short distance driving causes extra buildup because the engine runs richer and internal tolerances are not yet perfect since metal expands once it reaches a certain temperature. Not only will lots of stop and go as well as aggressive driving increase this, but doing frequent short trips (turning the engine on and off many times in a short period of time is also known to cause buildup.)

We know that aggressive driving CAN cause buildup because quality of fuel is poor which means an excessively rich air/fuel ratio. The reason why giving her an occaisonal italian tune up can help clear out carbon deposits (provided they are still fairly minor) is because 2-3 repeated pulls to near redline will heat up the intake ports enough to remove some deposits within the engine.

The main reason; in my eyes is the oil being used. It boils down to what sort of additives are added to the oil supply which help combat the process of oil shearing once fuel begins to dilute the oil in your crankcase. So while the correct additives is key, its also important to use a sufficiently thick oil weight as this will help further limit the process of oil breaking down and also ensure a better seal between the cylinder wall and piston ring which is crucial at limiting fuel dilution - which consequently causes blow by... and carbon buildup.

Lastly; let's not forget that the oil also passes through the turbocharger which means it is being subjected to an insane amount of stress and shearing force. this highly increases the need for good quality oil of a sufficient weight.

[JonEQuest]

Originally Posted by arkie6

What you have now is functionally no different than the stock setup for the high side PCV system other than having an OCC in the line. And apparently your OCC isn't doing a good job of separating the oil out of the air stream. Maybe the OCC is being overloaded? You may have high blowby internal to the engine is why you are seeing large amounts of oil in the pipes. If you open the oil filler cap in the valve cover with the engine running, do you get a large outflow of air and oil vapor? If you put a piece of paper over the oil fill hole, does it stay in place or get blown off? How many miles on your engine? How much boost do you run? How many miles can you drive before the engine is a quart low in oil?

I think I have this licked now. I removed my stock PCV, then cut the end off my stock PCV plastic cap and threaded in a barbed fitting. That hose goes few inches to a metal Toyota Supra PCV valve that continues on to a second catch can, that of course is connected to manifold vacuum from a barbed fitting I added for my BOV. I think that by blocking the ports but NOT doing anything else with my stock PCV system I was pressurizing the crankcase making more oil blow to the rear turbo. Now that I added the second catch can all seems good even after driving on a 350 mile road trip. I feel dumb for not addressing the stock PCV earlier since blocking the ports means it has to go somewhere. I saved a $hit ton of money by making my own "external PCV" valve with a $3.49 fitting from Home Depot and a $3.99 metal PCV from O-Reilly auto parts.

[Serf27]

Nice! It is a lot cheaper if you block the head ports rather than the PCV delete I used.
I’ve had my system on for about 500 miles. I can’t notice anything different. The other day smoke was coming out of the exhaust for some reason. Hasn’t smoked since. Odd.
The PCV catch can is catching oil. The inlet catch can isn’t catching much I think.

[Soden82]

Originally Posted by JonEQuest

I think I have this licked now. I removed my stock PCV, then cut the end off my stock PCV plastic cap and threaded in a barbed fitting. That hose goes few inches to a metal Toyota Supra PCV valve that continues on to a second catch can, that of course is connected to manifold vacuum from a barbed fitting I added for my BOV. I think that by blocking the ports but NOT doing anything else with my stock PCV system I was pressurizing the crankcase making more oil blow to the rear turbo. Now that I added the second catch can all seems good even after driving on a 350 mile road trip. I feel dumb for not addressing the stock PCV earlier since blocking the ports means it has to go somewhere. I saved a $hit ton of money by making my own "external PCV" valve with a $3.49 fitting from Home Depot and a $3.99 metal PCV from O-Reilly auto parts.

I just stumbled upon this thread and was going to tell you the same thing you just discovered on your own.

Personally I kept my flapper valve to rear inlet stock as I'm running the RB external PCV setup. I could do a high side catch can for catching blow by while in boost but from what I've seen from others they don't catch much oil, if any.

Just don't know if it's worth the $150+ for a high side catch can to catch negligible blow by

[JonEQuest]

Originally Posted by Serf27

Nice! It is a lot cheaper if you block the head ports rather than the PCV delete I used.
I’ve had my system on for about 500 miles. I can’t notice anything different. The other day smoke was coming out of the exhaust for some reason. Hasn’t smoked since. Odd.
The PCV catch can is catching oil. The inlet catch can isn’t catching much I think.

I also plugged the ports with alan screws when I rebuilt the engine. From NOT doing proper PCV venting after the rebuild I ended up gunking up my intake valves again after only ~3,000 miles. That is why I think I had so much blow by to my high pressure side catch can that ended up going into the rear turbo inlet, inter cooler, valves, etc. The pressure had no where to go. Now I have 2 catch cans (high side/low side) and I retained the high side flapper since it is there for a reason. The reason I used that cheap clear hose for the low side vacuum is so I can see if oil starts to get past the catch can. I plan to add a clear section to my high side catch can as well, that can had a useless oil separator so I added a brass filter and a flap of metal inside of it.
This was my first engine rebuild ever so I took my time and learned a lot. I just overlooked/forgot to take care of the PCV system properly. I am currently (2 weeks now) running 22lbs of boost on TD04-17T turbos and it has not blown up yet, so I must have done something right.

[Sgop335]

Originally Posted by JonEQuest

I also plugged the ports with alan screws when I rebuilt the engine. From NOT doing proper PCV venting after the rebuild I ended up gunking up my intake valves again after only ~3,000 miles. That is why I think I had so much blow by to my high pressure side catch can that ended up going into the rear turbo inlet, inter cooler, valves, etc. The pressure had no where to go. Now I have 2 catch cans (high side/low side) and I retained the high side flapper since it is there for a reason. The reason I used that cheap clear hose for the low side vacuum is so I can see if oil starts to get past the catch can. I plan to add a clear section to my high side catch can as well, that can had a useless oil separator so I added a brass filter and a flap of metal inside of it.
This was my first engine rebuild ever so I took my time and learned a lot. I just overlooked/forgot to take care of the PCV system properly. I am currently (2 weeks now) running 22lbs of boost on TD04-17T turbos and it has not blown up yet, so I must have done something right.

When you say plugged the ports, you’re referring to the port to the intake manifold correct? It opens in to the cap .

[JonEQuest]

I mean the the 6 little passages that feed oil down from the valve cover to the 6 intake ports. I think that may also be what you are describing. I now run an external PCV. It is literally between the stock cap I cut and added a barb to, and the oil catch can. I have each end of it shoved into the two hoses that go between the valve cover and can.

[JonEQuest]

Originally Posted by Soden82

I just stumbled upon this thread and was going to tell you the same thing you just discovered on your own.

Personally I kept my flapper valve to rear inlet stock as I'm running the RB external PCV setup. I could do a high side catch can for catching blow by while in boost but from what I've seen from others they don't catch much oil, if any.

Just don't know if it's worth the $150+ for a high side catch can to catch negligible blow by

It is definitely not worth a $150.00 catch can, which is why I bought one for $19.90 that is just as good as the other ones.

[Soden82]

Originally Posted by JonEQuest

It is definitely not worth a $150.00 catch can, which is why I bought one for $19.90 that is just as good as the other ones.

Do you remember where you bought it?

[Serf27]

Originally Posted by JonEQuest

I also plugged the ports with alan screws when I rebuilt the engine. From NOT doing proper PCV venting after the rebuild I ended up gunking up my intake valves again after only ~3,000 miles. That is why I think I had so much blow by to my high pressure side catch can that ended up going into the rear turbo inlet, inter cooler, valves, etc. The pressure had no where to go. Now I have 2 catch cans (high side/low side) and I retained the high side flapper since it is there for a reason. The reason I used that cheap clear hose for the low side vacuum is so I can see if oil starts to get past the catch can. I plan to add a clear section to my high side catch can as well, that can had a useless oil separator so I added a brass filter and a flap of metal inside of it.
This was my first engine rebuild ever so I took my time and learned a lot. I just overlooked/forgot to take care of the PCV system properly. I am currently (2 weeks now) running 22lbs of boost on TD04-17T turbos and it has not blown up yet, so I must have done something right.

The clear hose is a good idea. How do you think it will withstand the engine bay heat though?
Have you caught any oil on the high side catch can? Last I checked, I was about 100 miles in and the high side was bone dry and the low side had some oil in the catch can. I haven’t blown anything yet at 18-19 psi so it must too be working!

Originally Posted by Soden82

Do you remember where you bought it?

I know you asked JonE, but I’ll share what I did and what I used.
I made an in depth install video that still has to be edited if anyone is interested in viewing it, I’ll get on that.

2’ of 3/4” hose from auto parts store. ~$11
5’ of 3/8” fuel/vapor hose from auto parts store. ~$17
Pack of various T fittings for 3/8” hose -$6
VTT PCV delete fitting $40
RB internal PCV valve(used externally) $40
Low side catch can $20
https://www.ebay.com/itm/Cylinder-Al...72.m2749.l2649
High side catch can. Was $20 when I bought it.
https://www.ebay.com/itm/Billet-Alum...4AAOSw0~5en-~C
Then some hose clamps and aluminum plate I had to mount it.
Yikes, added up quickly! This set up didn’t require plugging the head ports, but still bypasses them. If you have your VC off, then JonE’s way would be cheaper because you’d save on the VTT PCV delete.

Looks like this now.

[Sgop335]

Originally Posted by JonEQuest

I mean the the 6 little passages that feed oil down from the valve cover to the 6 intake ports. I think that may also be what you are describing. I now run an external PCV. It is literally between the stock cap I cut and added a barb to, and the oil catch can. I have each end of it shoved into the two hoses that go between the valve cover and can.

Looks like your supra valve is sitting between the brass barb and the occ. instead it may be better to have the supra valve between the occ and the intake manifold port?
That way the occ is not pressurized each time the intake man sees boost.

[Soden82]

Originally Posted by Serf27

The clear hose is a good idea. How do you think it will withstand the engine bay heat though?
Have you caught any oil on the high side catch can? Last I checked, I was about 100 miles in and the high side was bone dry and the low side had some oil in the catch can. I haven't blown anything yet at 18-19 psi so it must too be working!

I know you asked JonE, but I'll share what I did and what I used.
I made an in depth install video that still has to be edited if anyone is interested in viewing it, I'll get on that.

2' of 3/4" hose from auto parts store. ~$11
5' of 3/8" fuel/vapor hose from auto parts store. ~$17
Pack of various T fittings for 3/8" hose -$6
VTT PCV delete fitting $40
RB internal PCV valve(used externally) $40
Low side catch can $20
https://www.ebay.com/itm/Cylinder-Al...72.m2749.l2649
High side catch can. Was $20 when I bought it.
https://www.ebay.com/itm/Billet-Alum...4AAOSw0~5en-~C
Then some hose clamps and aluminum plate I had to mount it.
Yikes, added up quickly! This set up didn't require plugging the head ports, but still bypasses them. If you have your VC off, then JonE's way would be cheaper because you'd save on the VTT PCV delete.

Looks like this now.

I think I might use your second link and then buy tubing and fittings and make my own high side one. And attach it to the strut tower next to my other low side can.

[Serf27]

Originally Posted by Soden82

I think I might use your second link and then buy tubing and fittings and make my own high side one. And attach it to the strut tower next to my other low side can.

The only reason I got 2 different styles is because, the one in the second link accommodates the 3/4” hose needed to connect the flapper and the rear turbo inlet. It also mounts to the strut tower nicely.

The first link, which would be the side catching most of the oil came with a dipstick to check oil level and the various fittings it came with accommodated the 3/8” hose needed for the TB vacuum line and the PCV valve.

I used this set up because I didn’t want to take the valve cover off and plug the head for now.

[JonEQuest]

Originally Posted by Sgop335

Looks like your supra valve is sitting between the brass barb and the occ. instead it may be better to have the supra valve between the occ and the intake manifold port?
That way the occ is not pressurized each time the intake man sees boost.

Hmmmm. That may be a good idea. I assumed it was good to have it as close to the crankcase as possible but if it doesn't matter then after the OCC would be a good idea.

[JonEQuest]

(Serf27) I like the location of the front can with a bracket off the manifold. I may do that. My low side can is still just tie strapped in while I decide where to permanently mount it.

P.S. to the question of how that hose will hold up to boost. I am not sure it will last forever but I like being able to SEE the oil before it gunks up my valves. It collapsed under vacuum but a long spring inside the hose took care of that.

[Serf27]

Originally Posted by JonEQuest

(Serf27) I like the location of the front can with a bracket off the manifold. I may do that. My low side can is still just tie strapped in while I decide where to permanently mount it.

P.S. to the question of how that hose will hold up to boost. I am not sure it will last forever but I like being able to SEE the oil before it gunks up my valves. It collapsed under vacuum but a long spring inside the hose took care of that.

Thanks. I couldn’t find out where to put it and I didn’t like the zip ties I was using. This location is also easier to access rather than under the cowl.
I drilled a hole in the stud that holds the stock air box.

The spring in the hose is great! I’m probably going to add a clear hose too. Cleaning those valves was a pain.

[JonEQuest]

Originally Posted by Serf27

Thanks. I couldn’t find out where to put it and I didn’t like the zip ties I was using. This location is also easier to access rather than under the cowl.
I drilled a hole in the stud that holds the stock air box.

The spring in the hose is great! I’m probably going to add a clear hose too. Cleaning those valves was a pain.

Imagine having to clean them TWICE!! I was pissed that the rear turbo sucked in enough oil in a few thousand miles to gunk up my valves again. This time to clean them I took off the manifold and rotated the engine until they were closed and sprayed them with some good intake valve/carburetor cleaner, then scraped with a small screwdriver and scrubbed them with a toothbrush. I then used my wet vac with a 1' long piece of 1/2" diameter hose taped to the end to suck out the cleaner and gunk. Wet vac is my go to for many things. I wet vac out my water when I have needed to swap engines or turbos, replace radiator, etc. It beats dripping sticky coolant getting everywhere. Only hassle with sucking out oils is cleaning out your wet vac hose and canister later with some simple green and dawn detergent.

[Serf27]

Originally Posted by JonEQuest

Imagine having to clean them TWICE!! I was pissed that the rear turbo sucked in enough oil in a few thousand miles to gunk up my valves again. This time to clean them I took off the manifold and rotated the engine until they were closed and sprayed them with some good intake valve/carburetor cleaner, then scraped with a small screwdriver and scrubbed them with a toothbrush. I then used my wet vac with a 1' long piece of 1/2" diameter hose taped to the end to suck out the cleaner and gunk. Wet vac is my go to for many things. I wet vac out my water when I have needed to swap engines or turbos, replace radiator, etc. It beats dripping sticky coolant getting everywhere. Only hassle with sucking out oils is cleaning out your wet vac hose and canister later with some simple green and dawn detergent.

Man, I’d hate to clean them twice in such a little time period.
I cleaned them the same way you did. It took a while and made a bit of a mess.
I let the cleaner sit overnight then used a soap bottle pump to pump out any cleaner. I then blew air into the valves while using the wet vac to suck up anything blowing out. Left them clean but what a pain. Hopefully these catch cans help out!

[JonEQuest]

Originally Posted by Serf27

Man, I’d hate to clean them twice in such a little time period.
I cleaned them the same way you did. It took a while and made a bit of a mess.
I let the cleaner sit overnight then used a soap bottle pump to pump out any cleaner. I then blew air into the valves while using the wet vac to suck up anything blowing out. Left them clean but what a pain. Hopefully these catch cans help out!

It's gotta help. Plus now I am monitoring what is going past them by looking in the hose occasionally. The low side has a semi clear hose and I added a spring on the inside to keep it from collapsing.

[Serf27]

I changed my oil the other day.
It’s been about 8k miles with the catch cans, I think, I didn’t keep track.
Both cans have been catching oil, even the rear which I was told would do nothing by my friend.
The rear inlet can didn’t have much.
The front can attached to the throttle body and pcv had a lot. I’m not sure if I should be concerned with how much it caught or if it’s normal.

The stock diverter valve vacuum nipple on the intake manifold is now being used for a bov. The line to the bov is clear. Itlooks like some oil/fumes are still making it into the intake by the looks of the clear hose.

Here are some photos.
First photo is can between rear inlet and flapper on the VC
Second photo is of can between pcv and the throttle body vacuum line.
Third photo is the dipstick from the front can with the screwdriver marking where the oil level was at.
Fourth photo is of the clear bov line. I was also using the inline air filter for the bov line, it had oily residue and the small filter broke in half when I grabbed it. Probably due to the oil in it. I think oil is still getting into the manifold.

[Serf27]

I had to pull my intake manifold off to replace the starter. I took a look at the valves and they look as if there isn’t any catch can in place or as if the pcv delete (which blocks off the passage to the head ports) is not working.
My catch cans are still catching oil, but the valves looked dirty and there was a trace amounts of oil in the charge pipe/throttle body.

Now these valves, I cleaned very well last year. I didn’t Keep track of the mileage, but I’d say this is about 10-15k worth of miles.


What gives?