Jump to content
SAU Community

Vq25Det Oil Catch Can Setup?

luthepa1

By luthepa1,
in Four Door Family & Wagoneers

 Share

Recommended Posts

luthepa1 Contributor

luthepa1

Posted
Posted

Hey Guys,

Maybe a bit of a silly question but I want to install a oil catch can but not 100% sure on the how. Is it as simple as just putting inline? And I am thinking I want a oil catch can for the PCV hose drivers side and also on the intake passenger side. Do I need to use 2 catch cans or can I rig up one catch can for use on both side? And I want to keep it legal.

I want to do this as a bit of troubleshooting procedure more than anything. My car runs absolutely fine except I still see some smoke for a few seconds when reapplying throttle after a 10sec backoff decelleration @ 80kms or more. Or if the engine is warmed up and idling in park I rev it high, then the revs drop back down to idle and some smoke clears, but recently I tried this rev test on a hot 33*C days after 45mins of driving with aircon on and nothing! No smoke. So the issue seems intermittent. This issue only started after an accident where the wife snagged the exhaust and ripped it clean off which was only 1 month after a turbo upgrade/replacement as the original stock turbo blew up.

https://www.dropbox.com/s/1lvc2hgifqkuajy/Stag%20Smoke%20Blow%20Short.mp4

Paul.

Link to comment
https://www.sau.com.au/forums/topic/438831-vq25det-oil-catch-can-setup/
Share on other sites
scotty nm35 Grand Master

scotty nm35

Posted
Posted

It almost sounds oil pressure related, when the oil is hot it's thinner and has less pressure. Can you try a thinner oil perhaps? What are you running now?

Were the banjo bolts drilled out? Perhaps too much for your turbo seals?

Dropping a catch can in will show you if there is blow by etc, but it won't fix the underlying issue. Have you checked the PCV operation?

luthepa1 Contributor

luthepa1

Posted
  • Author
Posted

It almost sounds oil pressure related, when the oil is hot it's thinner and has less pressure. Can you try a thinner oil perhaps? What are you running now?

Were the banjo bolts drilled out? Perhaps too much for your turbo seals?

Dropping a catch can in will show you if there is blow by etc, but it won't fix the underlying issue. Have you checked the PCV operation?

Hey Scott. I thought one might have been missed but Craig said that all 3 were drilled out now.

Currently running 10w60 castrol edge performance. Was running motul chrono v300 10w40 for a year. The 10w60 has reduced the amount of visible smoke frequency. I say it only happens when driving @80km or more but really its when the engine reaches max vacuum then i apply gas again. I have a cheapy boost gauge with max vacuum reading down to -15psi. At idle its around -9 to -10psi (-7 to -8 in drive and stationary). But i noticed when I do that "zippy" driving in back streets using only 1st and 2nd gear the car reaches -15psi easy when its all phsyc'd up. This is when smoke become visual looking in rearview mirror.

Like you say I know the catch can wont fix the issue but at least maybe I can get a indication of how much blowby gas there might be. I just need to start doing things to troubleshoot.

PCV seemed to work fine but I replaced with brand new genuine nissan PCV about 6 months ago. Made no difference.

KiwiRS4T Grand Master

KiwiRS4T

Posted
Posted

Where is the smoke coming from? If its coming out the tail pipe then its the opposite of blowby - oil getting past the rings and there's not much you can do about it short of new rings! You could check by doing a leak-down test to se if its your valve seals.

scotty nm35 Grand Master

scotty nm35

Posted
Posted

I still think it might be the turbo seals, I have a Soarer I work on with a similar issue, nothing I do can stop the turbo seals leaking, but it isn't all the time, and mainly on decel.

Any chance you can drop the front pipe and check the dump for oil buildup? Shame the turbo is so hard to get to...

Drop two catch cans in if you can, it will at least tell you if there is an issue with the PCV or breather and rule them out.

luthepa1 Contributor

luthepa1

Posted
  • Author
Posted

I now have the ability to jack the car up on stands and work from home now. I'll try to have a look at the dump pipe for oil build up. Is it enough to look at it when cold? Or should I go for a hard drive then check (so super hot)?

After this might look into leak-down test. And still interested in getting catch cans.

scotty nm35 Grand Master

scotty nm35

Posted
Posted

Catch cans aren't hard to fit, there are a few photo's of my setup in here somewhere.

You can't drop the front pipe when it's hot, just check it for wet oil when cold.

A compression/leak down test is a good idea. I just bought a tester myself for $40.

  • 2 weeks later...
scotty nm35 Grand Master

scotty nm35

Posted
Posted

It all looks pretty clean, other than the intercooler piping. Could be coming from the rocker breather or the turbo seals.

Running a catch can will rule out the rocker breather, try it for a few days just venting under the car and see if the oil stops. Best if you clean the intercooler and piping so you can see if it is still filling with oil. If it is, it may point to a turbo drain problem, which isn't too hard to check anyway.

  • 1 month later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • soviet_merlin
      My BMW E39 528i touring

      By soviet_merlin · Posted

      What does it look like with highway driving? And yes, I had a similar thought as Duncan. It looks quite similar in my Stagea and I have made myself accept it as normal. Might have to look into it some day  
    • OST Micah
      RH9 R32 GTR Build Thread

      By OST Micah · Posted

      While I was waiting for the new parts to come in for the charge pipe and radiator I decided to do some turbo modification. The drive pressure (exhaust backpressure) was a lot higher that I thought it should be. For 32lbs of boost drive was 55lbs. The turbine housing is a 1.10AR and my turbo builder has suggested to go to a 1.25AR. To test if a larger AR would do anything to reduce drive pressure AND not spend any money I decided to hog out the divider in my current housing. I removed it from the inlet and the whole way through the housing.  After reassembly and testing it doesn't look like this modification did anything for reducing drive pressure or requiring more fuel (making more power). Oh well, it was worth a shot. We'll get some data at the track if it makes it past the 60ft. I also machined a $7 shift knob off Amazon to fit my Stillway shifter since I didn't like the Stillway shift knob. Next on the list was the radiator replacement and fabrication of a new intercooler tube that had no silicon coupler. No pictures of this - I was short on time each night after work to get this done and didn't stop to take pictures.  Next was to get the clutch disks out and replaced. Previously when installing the dogbox I had ordered a set of the same sintered iron disks I had been running because I switched to the 26-spline input shaft. I thought it was odd that they didn't have any markings or brand name on them like all my old disks had but installed them anyway. At the track I could not get the clutch to lock up using my normal strategies. After two track nights I reached out to the clutch manufacturer and ask their thoughts. They said they had to switch the material out because they were having trouble getting the original material and that this new material would not take to being slipped very well.  So out with the first set of 26-spline disks and in with the correct material 26-spline disks. While I had the trans out I added an inspection/service hole. I've wanted one of these for a while. Now I can have a look at things and change the front cover shimming when needed (clutch wear). I hustled and got the clutch change done in a few hours on a Saturday. Hopped in the car and drove home. On the way home I did a 1-3 pull. When shifting from 2nd to 3rd the core plug in the back of the cylinder head popped out and dumped all the coolant. Thankfully I was only 30 seconds from home and coasted it there. Datalog showed nothing unusual and 2.5psi of coolant pressure. That plug has been in there since 1992 but I guess it worked its way out. Pulled the trans AGAIN and replaced the plug, JB welded it in, and made a brace. Also deleted the head drain I had added in during the bearing issue fiasco.  I am currently changing my boost control plumbing to make it cleaner. After that is done I'll make another attempt at getting past the 60.
    • Murray_Calavera
      S1 rb25/s14 starting problem

      By Murray_Calavera · Posted

      Are you 100% sure this isn't tune related?
    • 25zenki
      S1 rb25/s14 starting problem

      By 25zenki · Posted

      140-150 across the board. At this point hoping the grounding harness fixes it. My grounds are all tied to the chassis and none to the battery. For SR and KA that’s never been a problem for me but had a few other guys here and Reddit who told me RB really like a very solid ground setup tied to the battery so going to try that next, I’m stumped if that doesn’t do it. Never had a car have spark and fuel and not fire off before. Only thing I can think is the spark is intermittent/weak because of grounds nothing else really makes sense at this point 
    • Nightmare_mistress_R33
      No Voltage At Fuel Pump

      By Nightmare_mistress_R33 · Posted

      I am having close to the same issue. Can you help me with what wire you grounded to get your pump to trigger?
×
×
  • Create New...