Jump to content
SAU Community

Recommended Posts

Rb head oil drain dimensions

Hi all,

I've been looking at buying a rear head oil drain kit for my 25/30 such as the one spool or Franklin engineering make.

However I work in a machine shop and could easily make such a drain myself, I was wondering however if anyone had one lying around they could take some measurements off (preferably vernier)

Mainly chasing total width, length of drain spigot, diameter of drain spigot, the dimensions of the oil ring groove, pcd of bolt holes. If anyone has the dimensions I'd be happy to make extras at a fraction of the cost! Thanks

Link to comment
https://www.sau.com.au/forums/topic/468397-rb-head-oil-drain-dimensions/
Share on other sites

8 hours ago, Chids34 said:

I would disagree that they don't do anything, many people have this oiling problems this is a pretty simple fix. At worst it avoids a potential problem.

If you are serious about preventing an oiling problem read (at least the last third) of this thread and you will realise that the rear head drain hasn't helped anyone:

 

7 hours ago, iruvyouskyrine said:

They sort of work, but not in the way you think they do. Read the oil control thread to get a more complete understanding of RB oil control.

I haven't seen any evidence that they have done anything good. In fact having seen what comes into the catch can from the sump breathers I can't see that piping that up to the back of the cam covers is a good thing.

  • 8 years later...

Bump on this to not make another post,

had a ‘head drain’ leak on me and have the engine out as we speak. Planning on just putting a new freeze plug back in , plug the tapped holes and just be done with that headache. 
 

Now I still want to relieve pressure to allow oil to pass down the blocks returns easier.
I’ve seen catch cans with multiple vents help folks with this issue on this forum. 
I’m wanting to make my own.

I have some pictures here of my setup if anyone can help how I should plumb and design the catch can I would deeply appreciate it !

 

rb25

Oil upgrades:

1.0mm restrictor

n1 pump/billet gears

extended crank collar 

extended sump with trap doors/w welded fitting

 

 

6DBEA0AF-BCBF-44AC-A7FE-BAB3235BEF4B.jpeg

AD4F2D1F-2C13-40ED-838D-3F1A1F7181FC.jpeg

Yeah the head "drain" is rather a sump/crank case vent.

My catch can stopped filling up after venting the sump to the catch can.

I have 4x fittings in mine, which is about 5Ls.

2x cam, 1x sump vent/catch can drain, 1x fitting back to the intake and a massive breather which can be blocked so it's a fully sealed system.

  • Thanks 1
21 hours ago, Papichulo96 said:

have some pictures here of my setup if anyone can help how I should plumb and design the catch can I would deeply appreciate it !

I personally would run 2x from the cam covers into the catch can, 1x sump vent to catch can (would mount this at a low point of the catch can, so it can also act as a drain). I would see if you can run a -12AN down there to improve venting and also draining. The head drain thing, just drain that back to the sump on the other side.

Catch can to be vented, unless you plumb or back to the intake.

  • Thanks 1
On 2/26/2025 at 3:22 PM, Dose Pipe Sutututu said:

I personally would run 2x from the cam covers into the catch can, 1x sump vent to catch can (would mount this at a low point of the catch can, so it can also act as a drain). I would see if you can run a -12AN down there to improve venting and also draining. The head drain thing, just drain that back to the sump on the other side.

Catch can to be vented, unless you plumb or back to the intake.

Awesome thanks for the reply Man! I already plugged up the back just cause I can’t take a chance on it leaking on me again haha. But i will fab a catch can with 2x for the cam covers and a lower one for the sump vent. 
 

Now as this will drain back as well , Is there any concern I should have of the oil being drained back. I don’t run e85 or anything .

 

2nd question is, from the picture does it seem that my sump fitting is above oil level? Silly question but I rather have someone’s experienced opinion lol 

No concern, especially not on E85 you won't really have an issue with moisture. You could put a ball valve on it and only open it when you're going to punish the car.

On daily commutes you wouldn't need it open to vent the crank case.

I would say it's above the oil, considering that looks like it would sit above the windage tray

  • Like 1

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


  • Similar Content

  • Latest Posts

    • Hey Dave, welcome aboard! Good to see another soon-to-be Stagea owner here. The wagons are awesome — plenty of space, still got that Skyline DNA, and loads of potential if you’re into mods. Definitely post up pics when you get it, everyone here loves seeing new builds. What model/year are you looking at?
    • See if you can thermal epoxy a heatsink or two onto it?
    • The other problem was one of those "oh shit we are going to die moments". Basically the high spec Q50s have a full electric steering rack, and the povo ones had a regular hydraulic rack with an electric pump.  So couple of laps into session 5 as I came into turn 2 (big run off now, happily), the dash turned into a christmas tree and the steering became super heavy and I went well off. I assumed it was a tyre failure so limped to the pits, but everything was OK. But....the master warning light was still on so I checked the DTCs and saw – C13E6 “Heat Protection”. Yes, that bloody steering rack computer sitting where the oil cooler should be has its own sensors and error logic, and decided I was using the steering wheel too much. I really appreciated the helpful information in the manual (my bold) POSSIBLE CAUSE • Continuing the overloading steering (Sports driving in the circuit etc,) “DATA MONITOR” >> “C/M TEMPERATURE”. The rise of steering force motor internal temperature caused the protection function to operate. This is not a system malfunction. INSPECTION END So, basically the electric motor in the steering rack got to 150c, and it decided to shut down without warning for my safety. Didn't feel safe. Short term I'll see if I can duct some air to that motor (the engine bay is sealed pretty tight). Long term, depending on how often this happens, I'll look into swapping the povo spec electric/hydraulic rack in. While the rack should be fine the power supply to the pump will be a pain and might be best to deal with it when I add a PDM.
    • And finally, 2 problems I really need to sort.  Firstly as Matt said the auto trans is not happy as it gets hot - I couldn't log the temps but the gauge showed 90o. On the first day I took it out back in Feb, because the coolant was getting hot I never got to any auto trans issues; but on this day by late session 3 and then really clearly in 4 and 5 as it got hotter it just would not shift up. You can hear the issue really clearly at 12:55 and 16:20 on the vid. So the good news is, literally this week Ecutek finally released tuning for the jatco 7 speed. I'll have a chat to Racebox and see what they can do electrically to keep it cooler and to get the gears, if anything. That will likely take some R&D and can only really happen on track as it never gets even warm with road use. I've also picked up some eye wateringly expensive Redline D6 ATF to try, it had the highest viscosity I could find at 100o so we will see if that helps (just waiting for some oil pan gaskets so I can change it properly). If neither of those work I need to remove the coolant/trans interwarmer and the radiator cooler and go to an external cooler....somewhere.....(goodbye washer reservoir?), and if that fails give up on this mad idea and wait for Nissan to release the manual 400R
    • So, what else.... Power. I don't know what it is making because I haven't done a post tune dyno run yet; I will when I get a chance. It was 240rwkw dead stock. Conclusion from the day....it does not need a single kw more until I sort some other stuff. It comes on so hard that I could hear the twin N1 turbos on the R32 crying, and I just can't use what it has around a tight track with the current setup. Brakes. They are perfect. Hit them hard all day and they never felt like having an issue; you can see in the video we were making ground on much lighter cars on better tyres under brakes. They are standard (red sport) calipers, standard size discs in DBA5000 2 piece, Winmax pads and Motul RBF600 fluid, all from Matty at Racebrakes Sydney. Keeping in mind the car is more powerful than my R32 and weighs 1780, he clearly knows his shit. Suspension. This is one of the first areas I need to change. It has electronically controlled dampers from factory, but everything is just way too soft for track work even on the hardest setting (it is nice when hustling on country roads though). In particular it rolls into oversteer mid corner and pitches too much under hard braking so it becomes unstable eg in the turn 1 kink I need to brake early, turn through the kink then brake again so I don't pirouette like an AE86. I need to get some decent shocks with matched springs and sway bars ASAP, even if it is just a v1 setup until I work out a proper race/rally setup later. Tyres. I am running Yoko A052 in 235/45/18 all round, because that was what I could get in approximately the right height on wheels I had in the shed (Rays/Nismo 18x8 off the old Leaf actually!). As track tyres they are pretty poor; I note GTSBoy recently posted a porker comparo video including them where they were about the same as AD09.....that is nothing like a top line track tyre. I'll start getting that sorted but realistically I should get proper sized wheels first (likely 9.5 +38 front and 11 +55 at the rear, so a custom order, and I can't rotate them like the R32), then work out what the best tyre option is. BTW on that, Targa Tas had gone to road tyres instead of semi slicks now so that is a whole other world of choices to sort. Diff. This is the other thing that urgently needs to be addressed. It left massive 1s out of the fish hook all day, even when I was trying not too (you can also hear it reving on the video, and see the RPM rising too fast compared to speed in the data). It has an open diff that Infiniti optimistically called a B-LSD for "Brake Limited Slip Diff". It does good straight line standing start 11s but it is woeful on the track. Nismo seem to make a 2 way for it.
×
×
  • Create New...