Originally Posted by TitosToy

why is it that when an engine goes bad.. 90% of the time is the rear rotor blew an apex seal? when i bought my spare engine it was the same thing.

Originally Posted by Karack

the rear rotor runs hottest and has fuel cut(in stock config.), those 2 factors do not help it's lifespan.

Originally Posted by RETed

You call that damage?

http://fc3spro.com/TECH/HOF/K2RD/k2rdhof01.html


-Ted

Originally Posted by RotaryResurrection

Driving after the fact has no bearing on the actual damage. The damage is done the instant the seal breaks and flies apart...3 revolutions is all it takes to destroy all the apex seals, and within a few seconds the engine has turned hundreds of revolutions and spit out all remnants of seal into the exhaust. From that point on, whatever is left of the rotor is just freewheeling, and most any remnants of seal still in the slot are forcibly locked in place because the rotor was distorted. The damage you see when you take apart a blown apex motor is the damage that happened in a split second. Doesnt matter if you shut it down right then, tow it home, and open it up, or drive it another year, the damage was already done.

Oh, and I have seen much worse than that.

I just took apart an auto FD with a 37k mile reman. All stock. The people test drove it up north and bought it, trailered it back home, unloaded it, and it blew the seals before they could get to the gas station to fill the tank up. It destroyed the rear rotor and rotorhousing. What's worse, through an improbable stroke of bad luck that I have personally observed a handful of times out of hundreds of teardowns, one of the pieces of dead seal exiting the rear rotor exhaust port (quite quickly) hit the inside of the turbo manifold in just the right way to find its way INTO the front rotor exhaust port and do damage inside that housing too. I know this because all the seals on that rotor were in perfect condition with not so much as a chip or dent. There were a few small scratches on that rotor, which was reuseable, but that housing was scratched in several places and is not reuseable.