NSX Health Check Service

[Kaz-kzukNA1]

Addition to the Main Relay and A/C CCU board, one of the common failure item is the cooling fan control unit.

Not only it controls the radiator fan but also it controls the A/C system. If your radiator fan or A/C condensor fans operate intermittently or didn't operate at all, you need to consider the failure of this device as well.


Mine was fine but as a precaution, I replaced it recently.
It seemed that it switches on and off the radiator fan more frequently than before but it could be just my feelings....

Kaz

[Sudesh]

Have to say this is a real nice edition to NSX mod's. I have the same complete setup and as Kaz said you can easily feel the difference.

Finally, I managed to find some time to work on my NSX.

I installed these on lots of NSX in the past and also provided some of the owners with the parts.
In fact, I had the parts for my NSX for a long time but there were lots of higher priority projects than the installation of these and thus, couldn't install them until recently.


The original pedal assembly. Type-R on the top and standard one at the bottom.
Both pedals have exactly the same mounting shaft point and angle upto the spring holder. Below that point, Type-R one has different angle and puts the pedal closer to the bulkhead.


The damper less joint. My master cut the original joint in the past and it was using metal diaphragm to act as the damper.


New joint installed.


Nothing new to me and exactly the expected result.

You will get extra feeling through the pedal on the movement of friction discs and release bearing, clutch folk, etc. This is probably one of the reason why Honda placed the damper on the original model as for most of the owners, it is a strange feeling through the pedal.

For me, the clutch bite point is now where it should have been from the beginning. Much closer to the bulkhead and easier to move the foot from the footrest to the pedal.
As my clutch is getting close to the end of its life, it was quite difficult to perform quick up-shift at high rpm with original pedal without any slip but with this new pedal, it's much better.

Next big job on my NSX is going to be the timing belt so I need to plan ahead this time.... Needs to look into the clutch and flywheel as well...

Before this, I will probably need to finish at least 3 timing belt services for other owners. Too old for this...

Kaz

[m666 edd]

Have to say this is a real nice edition to NSX mod's. I have the same complete setup and as Kaz said you can easily feel the difference.

Agreed. Something for the to do list maybe. How much is the part?

[WhyOne?]

Needs to look into the clutch and flywheel as well...

Hi Kaz,

I have been meaning to ask you about clutch / flywheel replacement for some time.

I know the parts are quite different between the NA1 & NA2 cars.

With the NA2 set-up I believe it is recommended that the dual-mass flywheel is replaced with the clutch. However, I have heard that it is not always necessary to replace this (very expensive) part - what are your views & experiences of this please?

Thanks,

Ian

[markc]

The original pedal assembly. Type-R on the top and standard one at the bottom.
Both pedals have exactly the same mounting shaft point and angle upto the spring holder. Below that point, Type-R one has different angle and puts the pedal closer to the bulkhead.


The damper less joint. My master cut the original joint in the past and it was using metal diaphragm to act as the damper.


New joint installed.


Nothing new to me and exactly the expected result.

You will get extra feeling through the pedal on the movement of friction discs and release bearing, clutch folk, etc. This is probably one of the reason why Honda placed the damper on the original model as for most of the owners, it is a strange feeling through the pedal.

For me, the clutch bite point is now where it should have been from the beginning. Much closer to the bulkhead and easier to move the foot from the footrest to the pedal.
As my clutch is getting close to the end of its life, it was quite difficult to perform quick up-shift at high rpm with original pedal without any slip but with this new pedal, it's much better.

Next big job on my NSX is going to be the timing belt so I need to plan ahead this time.... Needs to look into the clutch and flywheel as well...

Before this, I will probably need to finish at least 3 timing belt services for other owners. Too old for this...

Kaz

Hi Kaz,

Am I correct in assuming that it is the damper less joint that makes the real difference in feel here?

I can't really see how a lower bite point, courtesy of a different pedal angle helps? Personally I'm not a fan of low bite points as they force you to press the pedal lower/fully every time.

Have to say this is a real nice edition to NSX mod's. I have the same complete setup and as Kaz said you can easily feel the difference.

Kaz/Sudesh, did either of you try the damper less joint first i.e. without the different pedal? I'm thinking this might be the better option for me.

Last question, will the damper less joint work with the NA2 single plate clutch/dual mass flywheel?

Cheers

Mark

[Kaz-kzukNA1]

Hi Kaz,

I have been meaning to ask you about clutch / flywheel replacement for some time.

I know the parts are quite different between the NA1 & NA2 cars.

With the NA2 set-up I believe it is recommended that the dual-mass flywheel is replaced with the clutch. However, I have heard that it is not always necessary to replace this (very expensive) part - what are your views & experiences of this please?

Thanks,

Ian

Hi, Ian.

For JDM, there are two different clutch types used even for the NA2 so I will use the word ‘single’ and ‘twin’ instead of ‘NA1’ or ‘NA2’ to distinguish the clutch type.

For any clutch, it all depends on how it was used over the long period.

For both single and twin type, friction coefficient on OEM disc seems to be quite high. Therefore, it tends to wear down not just the friction disc but also the mating surface on the flywheel.

If you acted early enough before wearing down the friction disc and flywheel, it is fine to just replace the friction disc on single plate type for standard NSX model. If your flywheel is black, blue or any sign of strange wear, you should replace it.

However, unfortunately, visual inspection is not good enough for metal involving friction as heat will change the characteristic. Something fine when it is cold may not be the case when it is hot and clutch is the typical case. Even your flywheel mating surface looked fine when you open the Gbox, you may get judder or noise under high rpm shift or when it is at high temperature. This is why you need to know the history of your NSX.


I don’t have any experience but a while ago, I read good review on SoS Sports Clutch.
Considering the price, it may be a good alternative to the OEM single type.

Kaz

[AR]

Well Kaz I have my RPS/SOS Twin Carbon here and I am hoping one day to get it done by you if possible. I can tell you that it looks like a sperb piece of engineering.

[Kaz-kzukNA1]

Hi Kaz,
Am I correct in assuming that it is the damper less joint that makes the real difference in feel here? Mark

Hi, Mark.

It’s the combination of the damper less joint and the Type-R pedal.
Please refer to the next question onwards for the effect of pedal.

While the damper will eliminate the vibration/noise through the clutch pedal from Gbox, it changes the actual bite point depending on how you depressed the pedal.

Also, the initial movement of the pedal travel is absorbed by the damper that it will require longer pedal stroke to disengage the clutch.

I can't really see how a lower bite point, courtesy of a different pedal angle helps? Personally I'm not a fan of low bite points as they force you to press the pedal lower/fully every time. Mark

If the initial pedal height and stroke is the same between standard (dampened joint + normal pedal) and Type-R (damper less joint + Type-R pedal) setup, then you are correct.

However, with Type-R setup, there is no damper in the hydraulic system and thus, the clutch is disengaged with shorter pedal stroke.

Addition to this and for better access, Type-R pedal is using lower initial pedal height.
So, you can control the clutch with shorter pedal stroke and less movement of your foot from the foot-rest position comapred to the standard setup.
This will allow you the quicker clutch pedal action.

Kaz/Sudesh, did either of you try the damper less joint first i.e. without the different pedal? I'm thinking this might be the better option for me. Mark

I never installed just the damper less joint without the Type-R clutch pedal but if you look at the above points, you will know that there is no point in doing so. Similar to your comment above, most of the pedal stroke is wasted if you stayed with the standard pedal.

By the way, as you can imagine, it is not good to use just the Type-R pedal with standard dampened joint. Depending on the way you depress the pedal, there is a small chance that you may not fully disengage the clutch before shifting.

Last question, will the damper less joint work with the NA2 single plate clutch/dual mass flywheel? Mark

The hydraulic system components such as clutch master/slave/hose/pipe and most of the release folk components are the same between single and twin type clutch so you can use this setup on both clutch type.

Kaz

[Kaz-kzukNA1]

During the Health Check on my NSX, I didn’t like the small movement/rattle at the left side headlight unit so decided to replace the adjuster module.

Quite often, the adjuster shaft itself gets corroded causing excessive gap at the holder resulting in rattle at the unit.



As expected, it’s corroded…. The new part for my NSX. The parts no is different for later models so please be careful.
Comparison between the corroded and new one.

[Kaz-kzukNA1]

The corroded one.
The corrosion made the shaft fat and chewed into the housing resulting in quite big gap. This allowed the unit to rattle.

]
The replacement.
Obviously, there is no corrosion and thus, no gap between the shaft and the housing.


There are two adjusters for each headlight unit. The right side was still fine but probably not far from the condition of left side....

Kaz