This is going to take a story to catch you up on everything I've done in the last week but here goes.
1) As you know, when I turned on the pressurization system the turbine spun up but after a few minutes would overheat. It also would start off very strong but after a few seconds would slow down and stop producing much air.
2) Coming back from MN a few weeks back I noticed that the system wasn't turning off. After a few minutes it finally did though so I haven't used it since thinking there was a problem in the shutoff valve.
3) I have 3 superchargers for the system and 2 pumps. I finally decided it was time to see what was what and I pulled them both out of the airplane and started poking.
4) I tore the pump and superchargers apart and found problems with both. I decided to take the best looking parts out of both pumps and rebuild it with those. There were o-rings that needed to be replaced due to leaking and the main shaft connecting the motor to the supercharger was worn pretty badly and was actually flopping around in the shaft.
5) I had another gearbox that was much much tigher than the one that came out of my plane and I used it along with rebuilding the oil pump in it. I cleaned the fan blades and housing and reassembled it.
6) I made new gaskets for both units and reinstalled them into the plane.
7) I test ran it yesterday and couldn't get the system to turn on at all. I started diagnosing the problem and determined the shutoff valve was not running at all.
I removed it last night and reinstalled a good motor I had this morning. That fixed that problem and I again test ran it.
Here is where the strangeness starts:
1) When I turn the system on and the shutoff valve opens, the pressure drops from 3000psi to 500psi and stays there.
2) I shut everything down and checked my fluid levels in the tank and they were a bit low so I filled it up.
3) I test ran again and you can hear the turbine slowly startup but the pressure drops to 500 psi and it never gets going.
There was one thing I was supposed to do during this process that I did but wasn't happy about. I was supposed to fill the motor case with skydrol before starting it up. The issue here is that with me just replacing everything the hose was empty going down from the backside of the motor. So as I filled the motor body it was just draining out into the lines. This would have taken days to fill those lines back up so I quit.
I'm about to go pull the plug and see if I can get it full now but the confusing part for me is that when that shutoff valve opens it shoves 3000psi of skydrol through that motor input side and I would assume that it would fill it back up almost instantly when that happens.
Also, for me to totally lose all pressure I would assume something has opened up completely. I was thinking maybe I screwed something up when I rebuilt the pump and it is locked up. I am hearing it spinning though so it is at least trying to spin and I would assume if it didn't spin and was under a lot of load that it would build up pressure in the system, not totally lose it all.
Any ideas?
Glenn
