NSX Health Check Service

[Kaz-kzukNA1]

Hi, all.
Recently, I was helping one of the new owner here.

1. ABS
Once again, it was full of air and had to close the special ABS T-wrench several times before completely releasing the pressure from the accumulator.

It is recommended to flush the system every year or at least once in two years time. This also includes the four solenoids flush. Luckily, all four solenoids on this car were working fine and they were flushed without any issues. The reservoir was drained after each solenoid was flushed and after the fourth one was done, the entire system was flushed again for two times. By this time, the fluid released into the ABS T-wrench showed [edit] little air and ready for another year.

2. Driveshaft
Another regular maintenance item on our NSX. In order to speed up the process, I’ve re-built my spare right and left driveshafts just before receiving the car. It will include full re-built of pin roller bearing inside the roller assy as well as painting the joint housing.

[Kaz-kzukNA1]

The old driveshaft came off from the owner's NSX and the re-built one from my spare. Nicely painted in black as well....


On this NSX, someone worked on the driveshaft previously but decided to use tyrap instead of double loop metal band to secure the boot. No way….
It couldn’t hold the grease inside the joint and splashed the grease everywhere.


After lots of cleaning, the re-built driveshaft was installed. While working on the driveshaft, it would look quite scarely when all of the suspension bolts were removed.

[Kaz-kzukNA1]

3. MTF
During the driveshaft service, if you are removing the left side driveshaft, you will need to drain the transmission oil. This NSX was MT so it was also a good idea to remove the MTF strainer to check the state of the transmission.

The strainer cover was corroded severely and took some time to remove. It is so easy to break the tab holding the cover to the transmission case but if the corrosion is too severe, it is quicker to break the tab and replace it with a new one.

It looked as if the strainer cover was never removed in the past. There were several tiny metal dust/particle inside the strainer but after more than 90,000miles, it was not too bad. Unless you track your NSX regularly, I recommend using Honda MTF-3. Otherwise, you will feel notchy shifting especially in selecting 2nd gear on cold morning.


4. Suspension bolts
In order to remove the driveshaft, you will need to remove the suspension bolts including the alignment bolt. Just mark the camber alignment position and make sure not to mix up left and right.

As our suspension parts are made from aluminium, please do not use cupper grease on them. As you can see, they are marked with green colour from the factory showing that they were specially treated to prevent corrosion due to non-aluminium parts touching the aluminium suspension.
I normally apply thin coat of silicone grease and for 15 years, my suspension bolts are not corroded and always easy to work with. By the way, for this NSX, it took long time to deal with many bolts as they were corroded. I applied silicone grease for future service.

[Kaz-kzukNA1]

5. Main Relay
Another common failure on our NSX. The Main Relay.
When DBW (drive by wire) was introduced on NSX, the location of main relay was also changed.

It has different bracket compared to the original one and the part number is also changed.
Although the number on the case body is different, the internal circuit is exactly the same between the two.
Re-soldered the original one and wrote some information on the bracket for future reference. It will be replaced with the new one once the parts arrived from Japan.

6. Brake Fluid
During the test driving session, it was recommended to the owner to overhaul the brake system such as the master cylinder and callipers. However, the owner wanted to first just replace the brake fluid and then put the car on the brake dyno to test the brake torque before carrying out any brake service. Also, the car passed the MOT just recently.

Eventually, I couldn’t release the car to the owner for safety reason but I’ll touch on this later.

The original fluid… Black. It should be clear unless you are using special brake fluid.

[Kaz-kzukNA1]

7. A/C Climate Control Unit (CCU) and Cabin air temperature sensor
Regardless of the mileage, your A/C CCU will fail.

The CCU computer board was re-furbished and the Cabin air temperature was cleaned as it was making annoying noise.

Lots of dust inside the sensor. You can only clean it thoroughly by disassembling it. Now, it is smooth and quiet.


Now it is clean....

[Kaz-kzukNA1]

8. Rear Brake Calliper
During the Health Check, it was recommended to the owner to have full brake system overhaul. Also, the parking brake was not balanced correctly between right and left.
While tightening the spindle nut to about 330Nm at the end of driveshaft service, I noticed that the rear brake was nowhere near to the perfect condition. The Parking brake between left and right had massive offset and the right side calliper felt as if it was seized. I don't know how it manged to pass MOT recently...

So, picked up the phone and told the owner that although we didn’t agree about the calliper overhaul, I would not release the car because of the safety reason.
The owner kindly agreed to let me carry out the overhaul and these were what I found…

The piston dust boot had cut in one place and not installed properly. The parking brake cable pin was completely rusted and I couldn't even remove it before soaking it with penetrating oil overnight. This was also the cause of the un-balance of parking brake between Right and Left. The lower calliper slider pin was corroded and completely seized. I had to actually hammer it out...


And because of these issues, the piston was heavily rusted and the rust even got inside of the calliper body. Had to clean it for a long time...

[Kaz-kzukNA1]

There was no way I could re-use the piston so replaced it with new one.
The rear calliper overhaul kit with new piston, new bleeder plug and the cap.
The rust was so severe that it even managed to get inside of the bleeder plug hole. The bleeder had to be replaced.


Rebuilding the parking brake mechanism.
Using the OEM special tool to compress the spring used at the parking brake mechanism just behind the piston.

[Kaz-kzukNA1]

Almost there...
Using the piston tool to insert (rotate) it with the new dust boot and seal inside the calliper.
As always, it is important to check the installation of dust boot by first extracting the piston to a certain level and then rotating back into the calliper. Throughout the process, the dust boot should show no twist and the piston should move smoothly.


Finally,the new bleeder plug installed and also applied special grease at the parking cable pin to keep it lubricated until next service.


I hope the owner will come back again in near future to complete the rest of high priprity service items.

Regards,
Kaz

[goldnsx]

The original fluid… Black. It should be clear unless you are using special brake fluid.

Good job! The fluid, was this the first and single one ever filled into the system?

[Kaz-kzukNA1]

I hope not...

Having said this, the owner only got this NSX recently so who knows how old this fluid is....

This was not the first time I saw this level of brake fluid on NSX, unfortunately.

And it's not just UK based ones. The other day, LH drive NSX was at my place and the brake system was also very bad.

Hope it will be looked after well from now on...

Regards,
Kaz