>  Ken Welter wrote:

 Here is the final report on the seizure I had when I blew
 an
 oil line.

 As I predicted there is no damage to the e-shaft or
 bearings
 and in
 fact I will use the main bearings over again but the side
 housings
 and rotors are trashed do to the expansion of the rotors do
 to
 loss
 of cooling to the rotors.

 Also the corner seals, apex seals and rotor housings are
 in
 good
 shape but the side seals and the oil rings are also trashed.

     Ken

 The rotor only has to get hot enough to loose the press fit on the gear, and
 the gear will wiggle out and touch the iron. This happens from
time to time in
 racing if the oil cooling is not up to par. You can run a long time at 220
 degrees or higher on the oil temp, or turn up 9,500 RPM. but not both.

 The damage to the iron, and after that to the rotor is a simple lubrication
 failure. After the gear walks out a few thousandths and either the gear side
 wear land or the nongear side wear land, start to run on the iron with the
 lubrication running out the damage is done. Usually the seals keep the rotor
 centered (about) between the irons. Those lands seldom touch
anything. On some you
 can see scratches from crap in the oil going through that gap.

 If you run over hot oil and it happens to you that the rotor is
too thick and
 is dragging a bit, just put the rotor in a press and push it back
in. Or, you
 can sit it on a piece of plywood, put a piece of aluminum plate on the gear
 side, and whack it with a big hammer, like a hand sledge. Be sure that those
 land areas are smooth as silk. They are bearings that you are not
supposed to
 use. You can shine them up with 600 wet or dry silicone carbide
glued to a DA
 orbital sander and solvent running on them.
 Racing Beat will remove the gear and reinstall it with an internal snap ring
 that will prevent the gear from walking out ever again. But if you are not
 racing, it is pointless.

 The rotor clearance idea of shaving off the sides in a taper, is
to give more
 room for the rotor when screaming the engine and the crank flex and the
 racing clearances stack up and let a corner seal area on the rotor
touch the iron.
 Not usually a problem below 9,000 RPM in a 13B or 9,500 in a 12A. Unless of
 course, you dump in a 100 HP nitrous shot for takeoff. That crank
flex problem
 can be moved way up the RPM range by removing rotor and
counterbalance weight.

 In the case where there was a period of time where there was no oil pressure
 and wide open throttle, I would replace the bearings and destroy the
 (damaged?) bearings, so that they never find their way back into
another engine.

 Lynn E. Hanover

If you make a two piece e-shaft like the 20B you could probably get a center
main bearing in a two rotor engine for racing purposes.

Paul Lamar

  No saving these rotors Lynn as all the seals are welded solid into
the rotors, yes I guess I shouldn't be a cheep skated and should
replace the bearing.
  I just pulled a core motor down and starting to rebuild it and I
cant believe what good shape its in and best part is I got it free
from someone that was cleaning his garage.

   Ken

 
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