Jump to content
SAU Community

Rb25Det Neo Cold Start Knock. Piston Slap?

NeoMaggots

By NeoMaggots,
in Engines & Forced Induction

 Share

Recommended Posts

NeoMaggots Apprentice

NeoMaggots

Posted
Posted

Here is a video of the knock from underneath the oil pan. https://www.facebook.com/photo.php?v=10202158035533359&l=7946916124426248770 I shut the car down once the knock was over. After those first few it stops. Going to start tearing into it tomorrow. plans are to go over the timing belt/ tensioners. cut open oil filter see how that looks, and drop the oil pan have a look in there.

NeoMaggots Apprentice

NeoMaggots

Posted
  • Author
Posted

=x Full tear down is necessary you would assume from that mild knock? It only does it on full cold starts. Im going to drop the pan and check the crank for out of round, but only being able to get 2 points checked isnt proper ><

scotty nm35 Grand Master

scotty nm35

Posted
Posted

What oil filter are you using? If the anti drainback valve is leaking overnight it can take a few seconds to pump the oil up. Mine was doing a similar thing with a certain brand filter. I changed to K+N and never looked back.

Is it fine at all other times and just does this at startup? No other noises?

Ben C34 Grand Master

Ben C34

Posted
Posted

=x Full tear down is necessary you would assume from that mild knock? It only does it on full cold starts. Im going to drop the pan and check the crank for out of round, but only being able to get 2 points checked isnt proper ><

That seems pointless.

NeoMaggots Apprentice

NeoMaggots

Posted
  • Author
Posted

^ yeah I don't know what I was saying :domokun: well the motor is out of the car now, should be on a stand tomorrow. It was not the oil filter drain back valve, i tested it did not leak a drop :( Guilt-Toy seems to be correct. I'll know in a day or two. Pictures to come. And picking up a s2 long block tomorrow. Any chances I will be able to get it to work with my NEO ECU/Harness?

scotty nm35 Grand Master

scotty nm35

Posted
Posted

You pulled the engine already? I would have cut open the oil filter and dropped the sump to see if there was bearing particles first.

Keep us posted, I think the cas is different between the two engines, and a few other small differences.

NeoMaggots Apprentice

NeoMaggots

Posted
  • Author
Posted

Yeah the motor was in a 240sx super easy to pull. I was in need of a new timing belt and water pump a few seals and pulleys. No signs of bearing in the oil filter, my last oil sample came back pretty regular but there's no telling until I tear it down. Any tips for When I pull the head to keep any stray coolant from getting down the cyl. Don't want a bunch of glycol getting down there if everything ends up looking healthy and it was just a bad tensioner pulley or oil pump

GTSBoy Grand Master

GTSBoy

Posted
Posted

I asked because #6 can be leaned out by a bad plenum. Even without that possibility, #6 often suffers before the other cylinders because it runs hottest. I suppose you could/should go looking for things like bad injectors/plugs and possibly even oil squirters for other reasons why it might have pinged itself to death.

NeoMaggots Apprentice

NeoMaggots

Posted
  • Author
Posted

I'm assuming I should go ahead and port out this oil drain? if I do this and put in the restrictors should I still pop out that rear welch plug and install a drain right to the sump. (drift car) I would like to not need to install a drain.

post-113457-0-21893400-1381029707_thumb.jpg

GTSBoy Grand Master

GTSBoy

Posted
Posted (edited)

External vents are almost essential. If you don't provide them then ALL the air flow from the bottom of the engine up to the top has to pass up through the drains, against the flow of oil. The extra up velocity makes it hard to get the oil to go down. Add in some extra flow area, velocity goes down, drainage works better.

Edited by GTSBoy

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

    • Duncan
      Duncan's V37.......race car?

      By Duncan · Posted

      our good friends at nismo make a diff for it, I have one (and a spare housing to put the centre in) on the way. https://www.nismo.co.jp/products/web_catalogue/lsd/mechanical_lsd_v37.html AMS also make a helical one, but I prefer mechanical for track use in 2wd (I do run a quaife in the front, but not rear of the R32)
    • GTSBoy
      R33 persistent issues. P/steering and lag/misfire

      By GTSBoy · Posted

      What are we supposed to be seeing in the photo of the steering angle sensor? The outer housing doesn't turn, right? All the action is on the inside. The real test here is whether or not your car has had the steering put back together by a butcher. When the steering is centred (and we're not caring about the wheel too much here, we're talking about the front wheels, parallel, facing front) then you should have an absolutely even number of turns from centre to left lock and centre to right lock. If there is any difference at all then perhaps the thing has been put back together wrongly, either the steering wheel put on one spline (or more!) off, and the alignment bodged to straighteb the wheel, or the opposite where something silly was done underneath and the wheel put back on crooked to compensate. Nut there isn't actually much evidence that you have such a problem anyway. It is something you can easily measure and test for to find out though. My money is still on the HICAS CU not driving the PS solenoid with the proper PWM signal required to lighten the load at lower speed. If it were me, I would be putting either a multimeter or oscilloscope onto the solenoid terminals and taking it for a drive, looking for the voltage to change. The PWM signal is 0v, 12V, 0V, 12v with ...obviously...modulated pulse width. You should see that as an average voltage somewhere between 0V and 12V, and it should vary with speed. An handheld oscilloscope would be the better tool for this, because they are definitely good enough but there's no telling if any cheap shit multimeter that people have lying around are good enough. You can also directly interfere with the solenoid. If you wire up a little voltage divider with variable resistor on it, and hook the PS solenoid direct to 12V through that, you can manually adjust the voltage to the solenoid and you should be able to make it go ligheter and heavier. If you cannot, then the problem is either the solenoid itself dead, or your description of the steering being "tight" (which I have just been assuming you mean "heavy") could be that you have a mechanical problem in the steering and there is heaps of resistance to movement.
    • MissMintyR33
      R33 persistent issues. P/steering and lag/misfire

      By MissMintyR33 · Posted

      Little update  I have shimmed the solenoid on the rack today following Keep it Reets video on YouTube. However my steering is still tight. I have this showing on Nisscan, my steering angle sensor was the closest to 0 degrees (I could get it to 0 degrees by small little tweaks, but the angle was way off centre? I can't figure this out for the life of me. I get no faults through Nisscan. 
    • Dose Pipe Sutututu
      Dose's Sometimes DIY and Pay Someone Home & Boat Improvement Thread

      By Dose Pipe Sutututu · Posted

      The BES920 is like the Toyota Camrys of coffee machines. E61 group head is cool, however the time requirements for home use makes it less desirable. The Toyota Camry coffee machine runs twin boilers and also PID temp control, some say it produces coffees as good as an E61 group head machine.
    • 25debt
      MAJOR FUEL ISSUES 25det neo r32

      By 25debt · Posted

      And yes with a full tank it will hit limiter free revving or driving 6B6CDF6E-4094-426D-A9CB-6C553475FE36.mp4
×
×
  • Create New...