Re-using stock seals

[vex]

As has been said. The FSM is your friend when it comes to seals. I for one do not understand the thought process of individuals who 'do not use the old seals'. It's just a camp that doesn't make sense to me (no offense). I've gotten into a 'discussion' on the other forum about this once and it really boiled down to some one just wanting a 'feel good' reason about their engine (he literally said "I'd rather take the false sense of security rather than use the old seals).

If the seals are in-spec, then there's really no reason not to use them. Brand new seals still need to be spec'd before install and they also need to be checked for by the same criteria as the used seals. I've even done the math/research on this forum (this particular sub forum to which I'm referencing) about seal wear. Apex seals wear extremely slowly. I think I figured out barring any abnormal circumstance the apex seals would last a good 800,000 miles with peak conditions, but then factored in a measure of safety which brought the wear life down to around 3-400,000 miles. Though I'd have to double check what I wrote in the other thread to be certain (it dealt with oils).

Now with this comes a grain of salt. Some old seals are outdated by their material or design. For instance the 3-piece apex seals. I am of the belief that they should be replaced for the newer 2-piece design.

In all honesty the NA engine will be fine with some soft seals and springs if everything spec's out.

My wear numbers were a little off: http://www.rotarycarclub.com/rotary_...3&postcount=12

[RETed]

Apex seals generally need to be changed, especially on an original motor.
Check with FSM, but I think they are:
8.0mm new
7.5mm replace with new inner apex seal spring
7.0mm wear limit - replace apex seal

Side seals in general don't need to be replaced - FSM has wear limits.

Corner seals are the same as side seals.

If side or corner seals are out of spec, I'd question if the engine was overheated or loss of oil pressure or no oil injection / premix.
Excessive side and corner seals imply internal lubrication is inadequate.


-Ted

[RICE RACING]

You can do it by the book (Mazda rotary rebuild schedule) then it will be fine. Just makes sure you clean everything spotless and measure ALL of the things they tell you to do.