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Today at Atelier Kaz - Private NSX Enthusiast, ex-Honda R&D engineer with F1, Indy/CART background

Eng Refresh Stage 2 - 01

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Only managed to start working on my NSX recently as I was too busy with other projects.


On top of my Engine Refresh Stage 1 menus, I would like to wash the engine thoroughly especially at the Front bank area and replace the Lost Motion Assy (LMA) to the latest spec.

So, this is called as Engine Refresh Stage 2.

I will be taking the engine out together with the GBox and rear sub frame so it would make sense to service the brake callipers at the same time but I don’t think I have enough time for polymer coating them so may be next time.

Both drive shaft felt healthy so they are going to be left and although I wanted to work on the GBox to replace all of the synchros, hub rings, etc and possibly the CL, again, not enough time before working on the next NSX.
I want to have my injectors cleaned but don’t have any experience with the service within UK so will look into this later. I think at least one owner had it done for his NSX engine so I may contact him.


So, first thing first.
Compression check before start of the service.

I normally check my compression every 6 months or so and the figures showed exactly the same tendency as the one I carried out during last summer.
As this is my NSX, I’m happy to disclose the full data.

As always, the absolute figure depends on the engine temperature, cranking speed, timing of the measurement after the engine stopped, etc so it’s just a reference.

[psi]
#1: 240, #2: 242, #3: 248, #4: 239, #5: 244, #6: 245

My NSX is 94 JDM NA1 5MT with about 131K miles.
It’s my every day car so being driven in the hot, cold, wet, dry conditions.
I bought it as a new car in Japan and I’m the sole owner and because of my background, I know exactly what kind of services were carried out (almost all of them by me any way) on this NSX over the last 17 – 18yrs.





The original IG Coils.
As seen on many NSX, the rear bank ones showed the corrosion but because I kept applying the silicone grease regularly, it’s only the surface rust and none of the metals are bubbling and lifting themselves from their original position.





Front ones are very clean.







The Spark Plugs
As I used to use my NSX for R&D purpose, there are still several test parts carried over from the past. This is the Denso Iridium spark plug with super fine centre terminal. Good products but as NSX uses direct ignition system any way, not much benefit. The insulator body doesn’t show any corrosion yet so I may re-use them but will go back to the original NGK Platinum one.







Just place the protection cover over the rear end of the car with extra piece of mind by using the food wrapping to prevent scratching the panel.







Once the engine is out of the car, it’s not easy to apply huge torque at the crank pulley bolt so loosen it at this stage.


Always lock the crank pulley using the SST and loosen the bolt.
You must NEVER try to loosen the pulley bolt by locking the flywheel side or lock the pulley bolt and rely on the starter power to loosen it.

Our engine is 6 cylinders with V-angle design at 90deg.

Hence, in order to achieve equally spaced combustion, the crank pins are offset by 30deg.
So, if you run the stress analysis, you will see different force distribution around the pins. Although the specified torque for the crank pulley bolt is 245Nm, quite often, you will need to apply more than 1,000Nm to loosen it.

You don’t want to apply such amount of twisting force across the long crank shaft….
You won't be able to notice it unless you properly measure it but you could permanently kink the expensive crank shaft.

More to follow.

Kaz


Updated 04-05-2012 at 12:21 PM by Kaz-kzukNA1 (Lost link to the photo.)

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Engine Refresh Stage 2

Comments

  1. Senninha's Avatar
    Hi, Kaz.

    This is one set of blogs I shall be watching with interest ... and please stay safe if you are working alone.

    regards, Paul
  2. Kaz-kzukNA1's Avatar
    Hi, Paul. Thank you for the kind message. Will look after myself.

    Can’t wait to replace the LMA as I left some of the original ones on purposely for R&D purpose and they started to make more noise recently. Will be replacing the VTEC sol. filers as well.

    Kaz