Thruster88

I would not call any crankshaft breakage normal. As Paul points out in his vid, the front bearing is very short, the standard prop extension is too long. The crank is not properly supported.

What we need is Avid+, or Avid premium, $20 extra for the extra button press or two on the security computer back ground check. Good for those who only need occasional access to "secure" regional airports, same 5 year duration or make it 10 like a passport, then I think we would all be happy. If I was a journalist there would be many questions.

Weather looking fairly ordinary for Wedderburn over the weekend, fabulous for farming in central nsw, we need it.

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The fact that two independent sensors, pressure and flow, show a change at the same time and the change goes away with operation of the boost pump suggests that the problem may be real. How old is the pump in calendar from first use? They are supposed to be changed at 5 years so not a total waste of money to do it now. One thing you could do is remove the inlet fitting and inspect the internal filter screen, see the post above by Underwood.

Normally there is only a bypass on the electric boost pump. I think this is there because an example the facet pump as fitted to my musketeer has a filter in it that is quite fine and could become blocked so an alternative path is provided to maintain fuel flow. The fuel pressure gauge allows us to continually monitor the health of both pumps during pre start (boost) and flying, EDP.

I think we can agree that any fuel pump in a carburetor aircraft will contain two check valves that only allow fuel to flow towards the carburetor. Regardless of the arrangement of the two pumps, in series or parallel, one open check valve in either pump will not cause a loss of fuel flow if the boost pump is on.

One defective open valve in the engine pump cannot cause the electric boost pump to fail as well. Where did the fuel it was pumping go? Pilots should be able to draw a schematic of the complete fuel system in the aircraft they are flying from memory.

My friend and forumite RFguy did his first landing at my farm strip in his excellent Piper Archer yesterday.

Agree, I was wearing a Sony nc headphone, watching a YouTube on the big screen when RFguy landed at the farm recently. Lucky my 6th sense was working.

In your case the boost pump is possibly restoring a smooth fuel flow, masking a fault in the engine pump if that makes sense.

One possible cause, the engine pump has an intermittent fault in the inlet valve. When the valve acts up the pressure naturally drops. The increase in indicated fuel flow is due to fuel pulsing back and forth in the flow meter. If the flow meter is after the engine pump then the outlet valve could do this. Any time the boost pump is turned on in steady cruise flight the fuel flow INDICATION dramatically rises in my RV6a, has to be due to fuel pulsing. Fuel will pulse with a faulty valve.

I met Bryan and had a look through his hangar when I bought a Thruster single from Holbrook in 2021. He was an amazing craftsman, the cars were something else. The ultralight museum, also amazing.

Some motivation for you Danny, you may already watch Mark who fly's his bushcat from tassie to the main land on a regular basis.

Get the paper work amended and fly the remaining hours yourself. It would be a shame to give up now Some buyers might be suspicious, others would understand the situation if you really need to sell the aircraft.