Blog Comments

Because Koyo Racing Rad is cheaper than OEM one and yet better construction.

OEM one is recycled aluminum with two plastic tanks crimped at the top and bottom.
Two different materials with continuous thermal shock.
Eventually, the crimp will get weaker and start opening up resulting in leakage.

Sometimes, the hose connection neck at the bottom side of the rad will crack as that's the entrance of the hot coolant on our NSX.
On other production cars, it will normally enter from the top.

Koyo Racing rad is widely used in Japan including the race teams.
All aluminum so unless the welding gets weak, it won't crack.

Your radiator may survived 21+ years but that doesn't mean the cooling efficiency is the same as the new one.
Probably by now, reduced down to 50 - 75%.
Not sure where you live but probably fine for street driving condition.

Over the last 23years, I can't even remember how many times I replaced the radiator on mine for preventative measure as well as for R&D purpose.

Kaz

Kaz, why don't you use the OEM radiator when one needs replacing? Mine has lasted 21+ years. Just curious...

Very likely to be the design requirement due to target weight, limited space and most importantly, the future services.

With ACG mounted inside the V-bank and the Eng close to the side frame, not much space available yet it has to be able to move away when tilting the engine.
So, the designer came up with that narrow hanger style solution.
Considering the thickness of the material and the way it holds the weight, probably had to use cast iron.

There are many places on our NSX that the designers thought about the future services and applied clever design.
For example, the mounts, sub frame fixing bolt hole design, etc, etc.

As a side note, some of the aftermarket headers are not suitable for tilting the engine during the TB service.
The rear bank header will hit the rear cross beam or some of them won’t allow removing other bolts on the rear member.
Of course the OEM manifold and header are designed with this in mind.
This was one of the most important factor when I researched the aftermarket headers for my NSX.


Kaz

Surprise, surprise…..
In the background, the administrators and forumadmin were discussing about this issue and I even proposed to have the server reset but all of a sudden, the server decided to start working and this morning, many of us received 10s, 100s of email, notifications, etc, etc….

Probably some of you received the Platinum expiry reminder, etc as well.

Forumadmin did nothing on the server so if this was just coincidence, it’s a one in million chances.


I can confirm that the 'Send Email' feature was not working at least from Oct/16 and possibly even before.

I'm in the process of slowly replying back to 10s of email sent from you so hope you will get my reply soon….
We are still discussing about the software upgrade and possible reset in the future.

In the meantime, if you sent email but didn't receive my reply, please use your own email software and send it to the address mentioned in the main thread above.


Just tested the 'Send Email' feature again and for now, it's working.
Please note that the 'Image Verification' is still not working and very likely to be module being too old....


Thank you.


Kaz

Kaz, out of curiosity I've noticed that 3 out of 4 of the motor mounts are aluminum, but the passenger side engine mount (black) is not. At least there is some hint of rust on it, so possibly steel.
Any reason/thoughts as to why?

Thanks kaz

Hi, nobby.

There was limited set of 6,000 available for sale and from what I heard, it sold out within a few days.
Just checked the Japan Post online shop site again and it's still shown as 'sold out' so I don't think they are going to produce any more…..
Some people are selling on the Japanese auction sites such as Yahoo but with premium and not sure it's allowed or not.....
I only bought one so I'm afraid I'm going to keep it. Sorry...
It's based on the joint project between Japan Post and Honda so there is a chance that they may produce another set for different model (NA2 NSX-R???) in the future so will keep eye on it.


Kaz

Kaz

any way of still being able to order a set through you?

would be keen to get a set

The mount rubber gets tired over the time and exposed to heat so in my view, if you touch any of the mounts, I would carry out the full sequence of tightening the bolts/nuts in specific order.

When taking the eng/gbox out, in order to shift the A/C compressor without disconnecting the refrigerant lines, one has to remove the front cross beam which holds the centre bolt of the front mount so I must carry out the full sequence any way.

After all these careful adjustments on the engine through the Eng Refresh, you don’t want ending up with NVH issue from the mounts.

Unlike other production cars, the sub-frame is connected directly to the chassis frame without any bushes or active mounts and the eng/gbox assy is ‘hanging’ on the sub-frame and the main frame through the four mounts.

Kaz

Kaz, when you put the subframe back on, the passenger side mount and driver's side transmission mount need to be bolted back on. Since you haven't interrupted the integrity of the rear mount and front mount, do you need to go through the full sequence of tightening the mounts? Thanks!

what do you have this entire subframe assembly resting on while you work on the engine?

I took several videos in the past and uploaded on Youtube but there is no direct comparison of before/after just the valve clearance adjustment without changing any other parts.
I only adjust it as part of my Eng Refresh.

In my personal view, one should not touch the valve clearance on NSX engine until one really has to do so despite it is specified as part of the maintenance schedule in some of the countries.
With the eng kept inside the bay, it's not an easy task especially at the rear bank.
I used to spend even more time just for this task when I used to do it without taking the eng out.

After carrying out the Eng Refresh on my engine, I never touch it until after 60K miles or 10 years time whichever comes first and each year, I’m taking the eng compression but no changes in cyl tendency so I'm happy with it.

Kaz

Is it possible you recorded a video/sound before and after adjustment valves. I have seen on You tube your videos.
???

That o-ring is for the oil feed passage on both the intake and exhaust cam plates for cam shaft lubrication.
#1 cam holder/cap has Y-shaped channel where it meets that o-ring for the oil to be passed to the in/exh cam plates.

Oil pressure is controlled by the relief valve next to the oil pump depending on the crank rpm.

The oil passage to the VTEC is at the other side of the eng where the VTEC Spool valve sits.
You can see the shape of the channels at the side of the cyl head where the rocker shaft sealing bolt sits.
Normally, the rocker shaft is used for rocker area lubrication but when all the conditions are met, the spool valve will apply much higher oil pressure to it.
At the end of the rocker shaft, there is orifice control valve and this will keep the oil pressure high enough to engage the primary piston during the VTEC operation.


Kaz

The o-ring under the #1 cam cover: Is this the o-ring that is responsible for keeping higher pressure oil within the small channels that engage vtec (eventually leading to the synchronizing pin) and prevent it from spilling over around the rest of the head?

Back in business. Not 100% but access is now recovered.
Bit worrying as it seems to happen frequently recently....

Kaz

I took these video for one owner on NSX Prime who was doing DIY TB service in 2012.
For some reason, he got wrong advice from somewhere and very likely adjusted the TB tension at #5 TDC.
He claimed that the TB was so loose that he can spin the WP with just one finger.

Should be done only at 9 cam teeth from #1 TDC.

For the clarification, you never adjust the TB tension from #5 TDC.
Because I couldn't re-create such loose TB tension using proper method, the #5 TDC video was taken in order to point out the mistake.

So, it was not for 'to make sure' purpose like in your question above.
If one made the mistake, one should do the whole process from step 1, ie; remove the slack and then adjust the tension at 9 cam teeth/blue marking from #1 TDC.

Found the old post on NSX Prime. If you read the whole story, you will understand the background of these two videos;
http://www.nsxprime.com/forum/showth...=1#post1658743

Kaz

Kaz, in your videos (~4/2013), you showed 9 cam teeth after #1 TDC; but then you showed another video with 9 cam teeth after #5 TDC.
The video corresponding to #5 TDC demonstrated that you eventually were able to move the water pump pulley with ease which meant that the tension wasn't correct. I am assuming then you backed off the tension bolt 180degrees and let the spring tension it again, then retorqued the bolt.
Why did you do this procedure for both #1 TDC and #5 TDC, just to make sure? Thanks.

Use decent pulley holder like in 4th photo, period.
It will assist you a lot although you are going to have big time using it on the rear bank exh cam if you are keeping the engine inside the bay.
After removing all the slack (very important), follow 9 cam teeth sequence as per manual.


Kaz

Hi,
Do you have any tips while tension belt -arising out of your experience - or just stick to the repair manual.