I have installed an old Rotax 914 on my plane. Everything works as expected but it takes 30 seconds or more for the turbo to spool up. You can follow how it spools up on the MAP, starts at 32" and slowly slowly climbs to just under 40". Reaching 40" takes more than a minute, you any takeoff will be without full turbo.
I've checked everything. Compression is fine. TCU closes the waste gate and the cable is spring-loaded with 1 or 2 mm. TCU Seems to follow the throttle fine. The waste gate moves freely, I don't think it gets stuck. No leaks can be found on the pressure side after the turbo.
Ive adjusted the prop so full turbo gives a 5700RPM.
When taking off with my huge turbo-lag, the RPM will be 5300 or so.
My thoughts what could be wrong are
a) Could it be that the exhaust mufflers are leaking too much? Its an old engine, and there are some play in the intersections between the bent pipes and the part that joins all four.
b) Could the turbine wheel got stuck? I feel resistance when I try to spin it with fingers, but I can turn it. If I try to spin it, it stops immediately or after 1/8 rev. If so, can I lube it?
Any thoughts?
