I've had my 20B on a test stand all wired up and ready to run for
months.  But even after endless troubleshooting I haven't been able to
achieve a successful start.

Today I hooked up a compression tester and I've probably found the
problem.  Rotors one peaks out at 35 - 40 psi and leaks down the instant
I stop cranking the engine, rotor two peaks around 50 psi and leaks
slowly down, rotor three peaks and will hold about 60 psi.  I didn't own
a compression tester when I did the rebuild and figured since I replaced
practically everything but the rotors and housings I should be OK.

Any thoughts, comments, or suggestions before I start tearing down the
engine?

TIA

Jay

Remove the schrader valve from the compression tester and watch it
while the starter turns the engine over. It should equal pulse 70 to 80
psi three times in a row on each rotor.

Sounds like you have one or more stuck
apex seals. Remove the exhaust manifold and use a small screw driver
to push on the apex seals through the exhaust port. If you cannot
feel them move in and out under the influence of the springs you
have a stuck seal. Spray WD40 in there and keep trying.
Remove the plugs and put some auto transmission oil in the engine.
Turn it over a few times and let it sit over night. Then check the
seals again. Once you get it running it will clean itself up.

Are you mixing oil with the fuel?

Paul Lamar


I am mixing oil in the fuel Paul; I'll give your suggestion a try.  If it
works it sure would beat tearing the engine down.
Jay