I put this in general rotary tech, but figured I'd put it in here also...seeing how this is where I spend most of my time.

I'm doing my first every rebuild and because I don't have any local experience to turn to for advice I've found myself getting down right OCD about the condition of my parts. My thinking is that being my first time doing this I'm more apt to make mistakes. I'm overcompensating by being overly picky about the things I can control.

It's a S5 JDM 13B that I'm rebuilding. On teardown I kept track of the FC seals by rotor, but not by position on each rotor. I had to replace the front rotor and did that with an FD rotor. It came to me with all the seals intact. On that rotor I tracked them. Every corner seal went back where it came from. Each side seal went back where it came from.

I specced out each rotor before assembly and found that every one of the FD side seal to corner specs were within spec. .0025-.006. Not a single one of the FC side seal to corner seal were in spec. All the FC specs were at .007-.008.

One factor to keep in mind. I kept all the seals in ziploc bags. One of the FC bags got moisture in it and rusted the side seals and corner seals. So I was working with less options when it came time to measure specs.

 

ah, can you use two different rotors?

 

It depends on what combination you are creating. S5 turbo and FD rotors have the same compression. S5 n/a and turbo do not mix. S4 n/a and turbo also do not mix. S4 and S5 whether n/a or turbo do not mix.

 

So buy some new side seals and fit them to spec. That is, assuming you checked apex seal clearence and the rotor is still good.

 

If your rebuilding why not just replace all the seals and springs?

 

Um, yeah. If reusing seals, then you need to keep track of their location and place them in exactly the same spot from which they were removed.

 

I'm not asking opinions of what I should do with my engine. I'm simply posting what I found for others to use. I've read and heard some say never re-use, some say re-use but make sure they go back in the same slots, some say it doesn't matter at all.

Being my first rebuild I found what I measured interesting.

Money. Atkin's price on new side seals is $150. Why spend if seals are well within spec?

Agreed, that's what my first rebuild has taught me. I'll always tag the seals from here on out.