Jump to content
SAU Community

Recommended Posts

The difference between the nissan drive and a spline drive is like the difference between tightening a bolt with an open ender on a hex head compared to a 12 point socket on a 12 point head, massive difference in the torque you can apply before the head rounds off.

Mike, I was thinking of a collar fitted just the same way as you fit a regular one, press fit and locking screws directly to the crank. Same way as my collars, Jun ones and even the dodgy cheap ones being sold now that look like the flats are machined with an angle grinder.

for the cost of setting up an external pump i would not waste my time with any jap brand pumps, they are up around 2k now and the external pump setup isnt gonna cost that much if you source the parts yourself, and its alot simplier than people like to make out :P

I am leaving my built motor on a stand until i sort out my dry sump setup now, i dont want to risk it any longer with the Jun pump, its only done a few thousand km's but still the cost of replacing cranks and rods, etc is not worth risking.

Mike, I was thinking of a collar fitted just the same way as you fit a regular one, press fit and locking screws directly to the crank. Same way as my collars, Jun ones and even the dodgy cheap ones being sold now that look like the flats are machined with an angle grinder.

Yes I understand. It is just a terrible design in all honestly, regardless of how long it is, it's just a plain fail on Nissans behalf.

In that case it would be silly not to go a involute spline or similar, just need to get the fit right. I have seen splines fail a few ways, but it just comes down to good design and manufacture.

I agree with "unique1" save the f**king about and go external pump/wet sump.

Mike

I don't think anyone is saying that every N1 pump is going to fail, more that the chances of a failure are higher than with other pumps.

As for it being a build problem, that would imply Nissan can't build their own motors.... I'm sure I've posted this before, but this was my N1 pump off an 8,000km old R34 N1 motor that barely ever saw limiter or "hard driving":

DSC00013800x600.jpg

To me, that points towards either poor grade materials used in the pump, or Nissan not knowing how to build their own N1 spec motors. I'd say the former is more likely...

That looks like excessive clearance, hammer marks, followed by cracking.

How's the flanges on the crank collar?

If they are worn it won't matter what pump you use, it will still get hammered.

Cheers

Gary

Gary, yes any clearance and they will flog out in no time, like a keyway, spline or whatever!

From what "proengines" said I gather the collars are press fit and if they are then there should be nothing really to worry about. However, I wont be taking the chance when it comes to solving oil issues on my GTR.

Mike

Gary, yes any clearance and they will flog out in no time, like a keyway, spline or whatever!

From what "proengines" said I gather the collars are press fit and if they are then there should be nothing really to worry about. However, I wont be taking the chance when it comes to solving oil issues on my GTR.

Mike

We have used Greg's collars on quite a few engines, warm up the collar (in the oven), cool down the crank (in the fridge), push on and they lock up nicely with the temperatures equalised. Grub screws only a safeguard really. It's not the collar to crank clearance that's the worry, it's the collar OD to oil pump flange clearance that needs measuring. Greg's collars are a nice snug fit, ID and OD, never had a problem with excessive clearance. Maybe another reason why, like Duncan, we haven't had any issues with N1 oil pumps over 10 years of using them.

Cheers

Gary

I always recommend using a Nitto collar when using the Nitto pumps. They are machined to match the pump drive perfectly. I even fit the collar when using an R33 crank if there is any signs of wear.

Edited by DiRTgarage
We have used Greg's collars on quite a few engines, warm up the collar (in the oven), cool down the crank (in the fridge), push on and they lock up nicely with the temperatures equalised. Grub screws only a safeguard really. It's not the collar to crank clearance that's the worry, it's the collar OD to oil pump flange clearance that needs measuring. Greg's collars are a nice snug fit, ID and OD, never had a problem with excessive clearance. Maybe another reason why, like Duncan, we haven't had any issues with N1 oil pumps over 10 years of using them.

Cheers

Gary

hey greg - that n1 pump which recently failed, was that running 1 of your crank collars :D

That looks like excessive clearance, hammer marks, followed by cracking.

How's the flanges on the crank collar?

If they are worn it won't matter what pump you use, it will still get hammered.

Cheers

Gary

Gary, it was an R34 N1 motor, there was no collar.

I agree with excessive clearance, but as I said, this is how it came straight from Nissan.... less than impressed.

Would I use or sell another N1 oil pump?

post-38702-1250942533_thumb.jpg

post-38702-1250942552_thumb.jpg

post-38702-1250942477_thumb.jpg

post-38702-1250942493_thumb.jpg

NO!

Bloody obvious why the N1 pumps fail, the narrowest area of the lobe is right on the contact flat edge where it contacts.

Lucky big ends and mains still look like brand new and there is no other dammage.

Will change bearings as safety obviously.

I think a splined drive like the 2jz one below would be a better option

,as the failures seem to be common..cracking where the flats are machined on the gears.

If the flat pump drive setup was a bad design the SR20 would destroy oil pumps as well, yet they can run to 8500rpm all day every day on a stock oil pump,

To add to that, Harmonic damper to protect your oil pump? tell me how if a 700hp RB25 with stock harmonic damper has such bad harmonics, enough to crack and oil pump, how is it that the main bearings still look like brand new? hell they dont even look like the motor has ever ran and she has over 20 000km's since I built it.

I am chalking N1 pump drama down to either poor quality control (in material and/or manufacturing) or poor material spec

They are a I4. Not a longer I6.

Taking a wild stab here but a I4 is not going to have the crank movement a I6 has, especially due to weight and so on.

Nor are the forces/pressures there especially if hitting limiters and so on with all that extra spinning around.

Torsional vibration and harmonics are generaly worse in an I4 due to firing order and cyl sequence, also one of the reasons most I4's have ballance shafts to try help NVH

Large crank movement = toasted bearings, SR20's run main bearings pretty easy if not 100% dead on ballance when running over 400wkw yet dont break oil pumps running a near identical drive setup & dimensions to the RB... Rb on the other hand comes out with bearings looking like brand new yet oil pump is scrap metal, The RB pump is driven not even 3-4mm from No:1 main bearing, pump gets damaged from movement but bearing isnt touched?

There is no way to have rotational vibration / whip without it running out of center.

....as the failures seem to be common..cracking where the flats are machined on the gears....

not all of them, mine howed no signs of wear at the crank but still cracked the outer gear in 3 places. Probable cause was crap running through the fine clearance of the pump causing it to crack.

Its clear that the fit between the crank and pump drive need to be checked for correct fit before use

Yes Rezlo an inline 6 is dynamically balanced, so no issue there.

It would be good to see the design of the SR next to the RB and compare. The RB does deliver more power and torque, it may be that the flat pump drive for the SR is "adequate" (as s**t as it is) and Nissan cut corners doing the same with the RB.

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

    • If as it's stalling, the fuel pressure rises, it's saying there's less vacuum in the intake manifold. This is pretty typical of an engine that is slowing down.   While typically is agree it sounds fuel related, it really sounds fuel/air mixture related. Since the whole system has been refurbished, including injectors, pump, etc, it's likely we've altered how well the system is delivering fuel. If someone before you has messed with the IACV because it needed fiddling with as the fuel system was dieing out, we need to readjust it back. Getting things back to factory spec everywhere, is what's going to help the entire system. So if it idles at 400rpm with no IACV, that needs raising. Getting factory air flow back to normal will help us get everything back in spec, and likely help chase down any other issues. Back on IACV, if the base idle (no IACV plugged in) is too far out, it's a lot harder for the ECU to control idle. The IACV duty cycle causes non linear variations in reality. When I've tuned the idle valves in the past, you need to keep it in a relatively narrow window on aftermarket ecus to stop them doing wild dances. It also means if your base idle is too low, the valve needs to open too much, and then the smallest % change ends up being a huge variation.
    • I guess one thing that might be wrong is the manifold pressure.  It is a constant -5.9 and never moves even under 100% throttle and load.  I would expect it to atleast go to 0 correct?  It's doing this with the OEM MAP as well as the ECU vacuum sensor. When trying to tune the base map under load the crosshairs only climb vertically with RPM, but always in the -5.9 column.
    • AHHHH gotchaa, I'll do that once I am home again. I tried doing the harness with the multimeter but it seems the car needed a jump, there was no power when it was in the "ON" position. Not sure if I should use car battery jump starter or if its because the stuff that has been disconnect the car just does send power.
    • As far as I can tell I have everything properly set in the Haltech software for engine size, injector data, all sensors seem to be reporting proper numbers.  If I change any injector details it doesnt run right.    Changing the base map is having the biggest change in response, im not sure how people are saying it doesnt really matter.  I'm guessing under normal conditions the ECU is able to self adjust and keep everything smooth.   Right now my best performance is happening by lowering the base map just enough to where the ECU us doing short term cut of about 45% to reach the target Lambda of 14.7.  That way when I start putting load on it still has high enough fuel map to not be so lean.  After 2500 rpm I raised the base map to what would be really rich at no load, but still helps with the lean spots on load.  I figure I don't have much reason to be above 2500rpm with no load.  When watching other videos it seems their target is reached much faster than mine.  Mine takes forever to adjust and reach the target. My next few days will be spent making sure timing is good, it was running fine before doing the ECU and DBW swap, but want to verify.  I'll also probably swap in the new injectors I bought as well as a walbro 255 pump.  
    • It would be different if the sealant hadn't started to peel up with gaps in the glue about ~6cm and bigger in some areas. I would much prefer not having to do the work take them off the car . However, the filler the owner put in the roof rack mount cavities has shrunk and begun to crack on the rail delete panels. I cant trust that to hold off moisture ingress especially where I live. Not only that but I have faded paint on as well as on either side of these panels, so they would need to come off to give the roofline a proper respray. My goal is to get in there and put a healthy amount of epoxy instead of panel filler/bog and potentially skin with carbon fiber. I have 2 spare rolls from an old motorcycle fairing project from a few years back and I think it'd be a nice touch on a black stag.  I've seen some threads where people replace their roof rack delete with a welded in sheet metal part. But has anyone re-worked the roof rails themselves? It seems like there is a lot of volume there to add in some threads and maybe a keyway for a quick(er) release roof rack system. Not afraid to mill something out if I have to. It would be cool to have a cross bar only setup. That way I can keep the sleek roofline that would accept a couple bolts to gain back that extra utility  3D print some snazzy covers to hide the threaded section to be thorough and keep things covered when not using the rack. 
×
×
  • Create New...