Paul (or anyone<G>).....

Any hints, short of teardown, to make sure the seals are  free and if

stuck how to free up?<<

Good question...I've been meaning to ask the same myself, as I seem to
have a stuck seal from time to time on my 87 RX-7, FI 13b.

I have 130,000 miles on it, and occasssionally, when starting it, the
engine spins freely, no apparent compression.  Within a minute or so, it
appears to work again. I'm assuming the seal frees up and again is
tracking the housing, but by then there is so much oil in the engine that
it has a hard time firing the fuel mix.

When it finally does start and run, for the first couple of minutes it
completely covers the neighborhood in that tell-tale blue smoke...until
the oil clears out.  It may start and run fine for several weeks after
that.  I carry a set of jumper cables in it now, just on the off chance
that it does that away from home and I run the battery down trying to
start it.

It has happened about a half dozen times over the last 10,000 miles and
doesn't seem to matter whether it's summer or winter, or whether the
engine has recently been run, and is warmed up, or if it's been sitting
for a week.

Sounds like a stuck apex seal to me (no apparent compression for 20 or 30
seconds of cranking).  Is there a way to free it up, or clean it out
without taking everything apart?  Like that water injection talked about
in a recent thread here?

Harley

Sounds like you may have a melted oil O-ring and the engine is getting
excessive oil in the combustion chamber that is clogging the seal slots
with carbon. You could take the top off the air cleaner and spray 
some water in the carb while the engine is warmed up and running at 
moderate RPM and see if a lot of black smoke comes out. That may or 
may not get the carbon out of the seal slots. 
Use an empty 409 bottle to spray the water.

The real fix is to take it apart, clean it up and at least put new 
O-rings in it. Course with all that work you might as well put
new seals in it too. Also check your EGR valve. Could be stuck open.
If you are not in a state that checks smog you might want to disable EGR. 
Also disable the injection pump and start mixing two cycle
oil with the gas. Running two cycle oil for a long time might
clear some of the carbon but I am not sure about that.

Paul Lamar
 
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