NSX Health Check Service

[Kaz-kzukNA1]

Hi, all.

For 15 years, I have been carrying out the Health Check on my NSX every 6 months as long as I was in the country.

I better remind the owners who visited my place around spring time for another Health Check session and possibly replacing the Eng Oil at the same time if it has not been done yet.

So, although I was very busy over the last several months, I managed to find some time to carry out the Health Check on my 94 NSX. As I always get similar questions about this service, here is some information for you.

1. The check sheet

This is the same sheet that I use for everyone. It covers about 150 points and if the owner is happy for me to drive his/her NSX, I’ll include several points from the short test driving session. It will enable me to feel the brake, alignment, clutch, AT, tyre and so on.

2. The Prioritised Health Check Report

After the Health Check, you’ll receive the report with prioritised future service recommendation in three different priorities. Following is one of the example reports that I sent to the owner recently.

Then, using this report, we can discuss about which services to be carried out in the near future based on the available time and also the budget.
Also, you need to think ahead and be prepared for some of the services required based on the mileage.

This time for my NSX, I replaced the Eng oil and the Oil filter then found the following points to be addressed.

[Kaz-kzukNA1]

1. Left side Headlight unit
Due to the design of headlight adjuster, the headlight unit tends to rattle after several years. Also, my NSX is the JDM and it doesn’t have electrical headlight height adjuster that doesn’t help the situation. Long time ago, I worked on this but it looks like they need another treatment.

2. Crank Pulley
My NSX has covered more than 123,000miles so based on JDM service interval, I was planning to replace the timing belt later this year. However, it looks like I don’t need to do it for several months.
As I need to replace the clutch at the similar timing that I am thinking of taking out the engine and gearbox out of the chassis so that I can carry out some refresh work inside the engine and the gearbox.
Having said this, I don’t want to delay replacing my crank pulley so decided to go ahead and replace it now.


The SST holding the Crank Pulley in place and the pulley bolt cleaned and greased properly. The original manual didn’t touch on how and where to clean/grease this bolt so some of the NSX required huge torque to loosen this bolt.
As in my previous post, I had to apply around 700Nm for one of the member here. The timing belt was replaced in the past but the pulley bolt was not greased properly. Mine came off with reasonable torque.


The new pulley.


The pulley came off from my NSX (left) and the one from one of the member here (right). The balancer split off from the pulley. You don't want to see this on your NSX....

[Kaz-kzukNA1]

3. Fuel Filter
It’s time to replace this again so waiting for the part to be to be delivered.

4. Air Filter
I use OEM filter and replace it regularly based on the mileage and/or visual inspection.
Hold your filter against the sun and if you couldn’t see it through, then it is best to replace it even if it hasn’t reached the specified replacement mileage.

5. Cleaning TH Butterfly and EACV
My NSX is not DBW model so it still has EACV for idle control. One of the reason why I don’t use aftermarket air filter is that some of them can release small amount of oil over the time and making TH butterfly and port for the EACV very dirty.
It’s time to clean the TH butterfly and EACV again. Regular cleaning will keep your idle rpm stable.


The front and back face of the TH as well as the internal wall of rubber accordion between the airbox and the TH body looked very clean so I’m happy.
Inlet chamber had some black mist due to blowby but quite normal for early C30A engine. On C30A later model and C32B, the routing of blowby was changed to cope with this oil mist in the blowby under high G cornering.

6. Battery
My battery will be 5 years old in November. As my NSX is everyday car, I don’t feel any weak cranking at the moment even in the cold morning but it’s best to replace it before it suddenly decides to give up. I may consider getting the dry cell type this time…..

7. Cleaning A/C evaporator
As in my previous post, unfortunately, our NSX doesn’t have any sort of pollen filter for the cabin air quality. Therefore, any dust, fume, leaves, etc will be sucked into the blower motor unit unless you are using the re-circ mode 100% of the time. This is regardless of whether you use the A/C or not. Anything managed to get inside the blower motor unit will be directed to the surface of A/C evaporator resulting in build up of horrible dirt or even mould…
If you don’t clean your evaporator regularly, then, you don’t want to know what you are breathing while you are driving… If you look at your cabin temperature sensor head located just below the ashtray in front of your MT/AT shift lever, anything trapped there will show you the quality of your cabin air. You may not be able to see the sensor if it was like the one from one of the owner here.



So, removed the battery, plastic drain channel, the cover, the blower motor and cleaned them all.
The quick filter that I made last time worked quite well as the inside of the blower motor was very clean.

[Kaz-kzukNA1]

Just quick clean on the evaporator and made another filter.


The filer goes under the plastic panel below the wiper arm under the bonnet.
If you are going to carry out this process, it would be best to get hold of some of the spare plastic clips holding the rubber weatherstrip under the bonnet as it is so easy to break them after long years.

8. Driver seat slide motor
I started to notice that when it was very cold in the morning, the fore/aft sliding motor/gear of driver seat made strange noise. It sounded like struggling to slide. When it’s warm, no problem at all. So, removed the driver seat and took it outside of the cabin. Re-greased the spiral guide and the seat rail and the noise disappeared.


I was also working on another NSX recently so I'll post the detail soon.

Kaz

[NSXGB]

Kaz,
What do you recommend for cleaning the TB? Something like this: http://www.toolstation.com/shop/Auto.../sd2795/p30713

Is it just a case of spraying it down the TB when the engine is running or spraying the TB with engine off and cleaning what you can with a rag, then a good dose while the engine is running?

[TheSebringOne]

Kaz, is this the 1st or 2nd crank pulley that you've changed on your car?

The one that you changed for a member here, what age and mileage of the car? I think from previous discussions the crank pulley is not on the servicing schedule? Is this best being done the same time as the timing belt?

[Senninha]

The pulley from one of the member here. The balancer split off from the pulley. You don't want to see this on your NSX....

I was looking for the large bolt that kept that one together until you could replace it

It would appear to be another of those preventitive changes worth doing for peace of mind ....

The filter goes under the plastic panel below the wiper arm under the bonnet.
If you are going to carry out this process, it would be best to get hold of some of the spare plastic clips holding the rubber weatherstrip under the bonnet as it is so easy to break them after long years.

Hi Kaz,

As always, thank you for the detailed info.

What is the process for removing the plastic panel please? Is it just the wiper arms and these clips to release it? Is there anything else that needs removal to access this filter and unit for cleaning?

Thank you

Paul

[Kaz-kzukNA1]

Kaz,
What do you recommend for cleaning the TB? Something like this: http://www.toolstation.com/shop/Auto.../sd2795/p30713

Is it just a case of spraying it down the TB when the engine is running or spraying the TB with engine off and cleaning what you can with a rag, then a good dose while the engine is running?

Hi, NSXGB.

Carburettor cleaner or similar products designed for cleaning intake manifold would be the safest thing to use.

Please read the instruction on the side of the can as some products will state to be used only when the engine is cold.
Never use brake cleaner for this purpose as it could trigger fire or even release lethal chemical in the air.

Be gentle on the TB and never apply any force. While the engine is off, open the TB and gently wipe off any dirt from the front/back surface of the TB. At the same time, spray small amount of cleaner into the intake channel and wipe off any black residue. Don’t spray too much otherwise you’ll struggle to start up the engine at the next step.

Start the engine and remove the PCV valve from the head cover. Spray the cleaner at the PCV valve in short burst several times.

For non-DBW model, the TB is closed at the idle rpm and the air is fed through the bypass port which is at the upper side of the TH body. Open the TB slightly to keep the rpm higher than the idle and spray the cleaner in short burst mode aiming at the bypass port.

Stop the engine and remove the clock fuse to reset the ECU.
Go out for a short driving to let the ECU to learn the new study value.

After this process, you may need to adjust the idle rpm so be prepared.
If you don’t know the procedure or don’t have the rpm monitor, it is best to let someone else to do the job for you.

Regards,
Kaz

[Kaz-kzukNA1]

Kaz, is this the 1st or 2nd crank pulley that you've changed on your car?

The one that you changed for a member here, what age and mileage of the car? I think from previous discussions the crank pulley is not on the servicing schedule? Is this best being done the same time as the timing belt?

Hi, TheSebringOne.

This is the 3rd pulley for my NSX although it will be my 2nd Timing belt service next time.

I don’t know the exact mileage/age when the balancer split off on the member’s NSX because he/she already spotted the issue before arriving at my place.
The service was carried out as an emergency case and the owner applied short term fix before arriving at my place. However, I do know that his/her NSX was used on the track many times.

While the mileage and age will play some factor for this issue, the biggest factor would be the driving condition such as the sudden change in RPM and the heat. So, for some owners, the pulley will be fine for more than 10 years whereas for some of us, it will fail earlier than that.

You will be surprised to know how heavy the balancer is and it is only held in place by the rubber.
So, inevitably, if you make sudden change in rpm, it will snap off after many years. You can’t judge it just by the mileage or the age. Also, you can't see it from outside as the balncer is hidden by the pulley.

Although it is not defined as regular service item, it is a common practice to replace this at least at the time of timing belt service among the people who works on NSX regularly in Japan.

For those who track their NSX or drive aggressively, it is best to replace it more frequently.

Regards,
Kaz

[Kaz-kzukNA1]

.....

What is the process for removing the plastic panel please? Is it just the wiper arms and these clips to release it? Is there anything else that needs removal to access this filter and unit for cleaning?

Thank you

Paul

Hi, Paul.

In order to access the inlet channel of the blower motor unit, you only need to remove the plastic pins (7 - 8 of them) holding the long sideway weatherstrip at the front of the plastic panel. Once the weatherstrip is off, you can lift the front section of the panel.

You can't remove the entire panel off the car without removing another trim at the bottom of the windscreen. I don't recommend removing this trim as it is held by special yellow clip and it is so easy to break it as it is getting very old by now.

There is no filter attached from the factory so if you are going to make something by yourself, you need to keep the bottom of your filter material well off the chassis panel to avoid absorbing the water. Any water will get in there through the meshed section of the top panel around the front suspension mount area and so on.

Obviously, you need to remove the blower motor unit to clean the evaporator.
In order to remove the blower motor, you'll need to remove the spare tyre holder, the battery, the relay box, the drain channel and disconnect the three connectors on the blower unit. You will also need to separte the cable clamp at the drain channel. You can get some idea through the manual but it is best to look at on your NSX as some of us installed aftermarket HID units, different battery, removed spare tyre holder and so on.
Be careful not to damage the two plastic pins/studs at the side of blower motor case holding the water valve and the coolant hose unit for the heater core.


Regards,
Kaz