CharlieWaffles
Well Known Member
Today we had the first start of my stock YIO-540-D4A5 with slick mags. The start was delayed as the Andair electronic pump appears to have a problem like described here http://www.vansairforce.com/community/showthread.php?t=98959&highlight=andair But we decided we could worry about that later.
We got the engine started using just the mechanical pump but the engine seemed to develop power for a short period of time and then loose power, stutter like the mixture was being pulled (which it wasn't) and come close to dying as if ICO and then recover shortly. After a few times it stabilized for a minute and then stuttered and died.
I suspect a fuel pressure issue. There are no leaks and the stock injector is at the full mixture setting - we tried a small amount of leaning to make sure, but it had no affect. Oil Pressure/temp is good.
I uploaded my data to SavvyAnalysis and graphed RPM and MAP (top chart) and RPM And Fuel Pressure (bottom chart).
Is this a fuel pressure issue and could the bad electrical pump be causing this? Perhaps if the internal works are restricting the flow or something else? The pump info says there is a check valve (doesn't give much info on it) but could the checkvalve be cracking open and allowing the air into the line and that is causing the pressure fluctuations?
We got the engine started using just the mechanical pump but the engine seemed to develop power for a short period of time and then loose power, stutter like the mixture was being pulled (which it wasn't) and come close to dying as if ICO and then recover shortly. After a few times it stabilized for a minute and then stuttered and died.
I suspect a fuel pressure issue. There are no leaks and the stock injector is at the full mixture setting - we tried a small amount of leaning to make sure, but it had no affect. Oil Pressure/temp is good.
I uploaded my data to SavvyAnalysis and graphed RPM and MAP (top chart) and RPM And Fuel Pressure (bottom chart).
Is this a fuel pressure issue and could the bad electrical pump be causing this? Perhaps if the internal works are restricting the flow or something else? The pump info says there is a check valve (doesn't give much info on it) but could the checkvalve be cracking open and allowing the air into the line and that is causing the pressure fluctuations?
![Capture-14_zpsa33c938c.gif](/community/proxy.php?image=http%3A%2F%2Fi1079.photobucket.com%2Falbums%2Fw513%2Fcheapguy69%2FCapture-14_zpsa33c938c.gif&hash=75219298ff825986f1d9c86162181c42)
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