Supercharge your SKX007 with a NH35

Edited : 4/4/2017 (add pix)

After doing the “Triple charge your Seiko SKX007 with Dragon Shroud, Jumbo crown and a NH36 !” article.
( ) .

I have been receiving many request to do a tutorial for  updating the SKX007 <or SKX009> to the later NE15 (6R15) or NH35 (4R35) movement while highlighting the necessary parts swap to make it work !

Since i do not have any similar project currently. I will be writing this tutorial basing on mine existing pictorial and Nicholas Hacko’s excellent 7S26 servicing pictorial.

For this “Supercharge your SKX007 with a NH35” tutorial, i am assuming that you have the tools and know how to remove the :

a) back case

b) stem

c) hands

c) dial

d) remove movement from the watch case


Lets begin with the parts swap.

NEW NH35 Stem
You will need a new NH35 stem (the 7S26 stem will not work with NH35 movement).
I have the pre-cut, plug and play NH35 stem here ( )
*the stem extender is provided free-of-charge if you are using the pre-cut stem for other application.

**below pix shows the stem differences.

NEW aftermarket crown
Original Seiko SKX007 crown and stem are not detachable. So a aftermarket replacement from the ebay will needs to be sourced.
*see the difference below pix.

OR Seiko’s SARB059 cr0wn
If you are a purist and really “MUST and INSIST” to use an original Seiko crown. Or using an aftermarket crown wouldn’t let you sleep in peace.
You can try to find the SARB059 crown [Seiko Part Number 1E70A7SNS0]. This crown has a detachable stem and is a direct swap on the SKX007 Case. For Bonus ! It has a “S” marking at the crown too !

OK, once you have the above sorted out. Next will be the plastic movement spacer.

NH35 movement comes with the gray plastic movement spacer. See pix below.

Seiko makes 2 type of plastic movement spacer the 2mm (Gray) and the 3mm (Black) spacer thickness.

Although it has been reported that the NH35 Gray spacer work well in the SKX007 watch case and swapping the thicker black spacer is not necessary. A little investigation reveal that the casing diameter is slightly bigger for the NH35 (which may explained the tighter fit and get away with it).

Anyway, we will do a proper job by also swapping the Seiko black plastic movement spacer into the NH35.

Most of the NH35 available in the market currently are 3pm DATE position. It fit well into the SKX dial but needs to transfer DAY wheels from the 7S26 to the NH35. (For NH36 with DAY/DATE, they are also at 3pm position. The DAY location will be misaligned when installed on the SKX dial. Similar works will needs to be performed too. So no difference buying the NH35 or NH36 movement !) .

Below Nicholas Hacko’s excellent DAY/DATE removal guide below [so i don’t have re-do this part] :

Remove the snap clip

Remove the day wheel

Remove the intermediate day correction wheel

Remove the 4 screws

Remove the plate

Remove the DAY/DATE setting wheel

IF you are just swapping the DAY wheel. Do the same for the other movement and install with reverse procedure.

That will complete your necessary swap required for “Supercharging your SKX007 with a NH35” !

Note : i am not taking calendar wheel colours into account at this stage.

IF calendar wheel colour is a concern, please proceed with additional steps below on swapping out the DATE wheels too !


Remove jumper plate

Remove date wheel

Do the same for the other movement and install with reverse procedure.


OK, there you have it. Hope you guys enjoy the “Supercharge your SKX007 with a NH35” !




  1. Richard Erickson · · Reply

    I am new to this whole swap movement thing but am willing to try it because my skx173 is annoying fast then slow, theme stops and not very accurate. Hopefully you can help me with a few things. I have a brand new Nh35 and a brand new seiko sarb 059 crown with stem attached. So, what I understand is all I have to do is: use black spacer with nh35 movement.
    Use the Sarb 059 crown, minus the stem and put it back together, no problem! Right???
    Hopefully I can get the stem off by taking the gasket off and putting it in hot water for a while before taking it apart! Does all this sound correct???

    1. Hi,

      Your understanding is correct !

  2. Thanks for sharing your knowledge! It was very helpful. We hope you don’t mind us sharing this with our followers.

  3. Reblogged this on Strapcode and commented:
    How to take your Seiko SKX007 movement out of the case

  4. […] Source: Supercharge your SKX007 with a NH35 […]

  5. Sure strapcode ! Go ahead and share it !
    Glad you enjoy it.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: