TSIO360FB fuel issue
I purchased a 1979 Piper Dakota Turbo in December and have been having quite the adventure with getting a nice balance fuel adjustment and also getting the engine to shut down in ICO position. Now after getting the fuel pump rebuilt, having seals replaced in the throttle body and spider assy (manifold valve), and lastly finding out that the Merlin wastegate was installed backward and the unit was stuck in the fully closed position, we have repaired or replaced these components.
The mechanic was finally able to get a nice balance fuel mixture with appropriate fuel flows and the engine would run smooth.....until mixture placed in ICO....then it will chug along for about a minute at 300RPM before finally shutting down.... Needless to say, two steps forward and one step back. My mechanic tested the ICO with the low electric pump and it was out of tolerance. Had a small stream coming out (the tolerance is less than 20 drops/minute. We sent the pump back to Central Cylinder in NE and they retested it every which was and could not find any leakage more than a drop, and that was at high pressure (20psi). My mechanic was test at about 6-9 psi.
Any thoughts out there? Was wondering if it was possible that there is a check valve stuck in the vapor return or something like that. Completely clueless at this point. One final thing, the aircraft had an off-field landing in 2000 due to engine failure (controlled landing with no damage). But the wings had to be removed to transport the plane back to the field. IA removed and re-installed them. Plane has been flying since, about 700hrs.
Comments
Please stand by while I send this to our association A&P, Erich Rempert for his comments.
Scott Sherer
Wright Brothers Master Pilot, FAA Commercial Pilot
Thank you
Hi, here is Erich's response:
Sounds like the mixture control (arm) is not hitting the cut -off stop as it's currently rigged.
If it tests good on a bench, and not in the plane, it has to do with the rigging of the mixture control.
Properly rigged engine controls will have "cushion" at both ends of travel of 1/4"-1/16". This ensures that the stops that are being hit are on the component they control, not in the cockpit.
~Erich Rempert, A&P Consultant
Scott Sherer
Wright Brothers Master Pilot, FAA Commercial Pilot
It has been hitting the physical stops (metal stops). But we are rechecking it again. Thanks for the info.