Jump to content

Gmon

Members
  • Posts

    18
  • Joined

  • Last visited

Posts posted by Gmon

  1. I have seen this a few times. Different things have fixed it, from adjusting engine throttle cable tension to replacing springs inside the throttle quadrant. I would look at everything from the throttle all the way the to the propeller valve housing. Check the all cable tension, ensure your throttles are passing all pull checks, and inspect all bearings, turnbuckles, rod ends, and bushings. I have seen engine and propellers replaced and the issue continued. Don't be quick to call first thing you find wrong as the fix, take the time to inspect the whole system.

  2. 2J-T56-101 used to have a P/N and NSN for the old corrosion carts. It also says you can locally fabricate a cart in lieu of the old corrosion cart. Hydroblaster.com sells pressure washers that can be rigged up as wash carts. Just look for one that pushes 10 gals per min, and an air compressor capable of 100 PSIG.

  3. All engine control rods should be inspected, bushings swapped for any play. If all rod ends have been inspected, whole gimble assembly has been swapped, and fuel control and coordinator changed, I would look outside the engine. I have seen springs within the throttle quadrant cause such a problem. Does the problem go away with the friction knob when it is tighten?

  4. You are correct, Steve. Fuel govern/pitchlock checks goes follows.

    throttles crossover

    lock valve

    retard RPM 1%

    hit governing check switches

    throttles to takeoff (this is topping/governing)

    retard throttles slow back to retarded RPM. (no longer governing)

    Torque increase of 500ibs let you know what you are pitchlocked, its normally higher than 500ibs. If its fluxing at this point the fuel control more then likely the cause.

  5. Its the other way around, when you do the pitchlock check, you hit the check switches and that cheats prop into not correcting RPM. Now the fuel control has to play its part in preventing an overspeed. With the propeller pitchlocked, the only thing left to control RPM is the fuel control. If the flux continues in a pitchlock, a fuel control would be suspect. If stops in during a pitchlock, more likely to points to the prop. Its not all definative either. Just when you do a pitchlock check the fuel control is only temporily in fuel governing.

  6. Disconnect the prop control C/P from another engine that is known as a good. Set-up everything as if you were doing a pitchlock check (throttles above flight idle, norm gov, synch to off, and no master selected) Get all the voltage readings from each pin (with the fuel gov check switch on and also with it off. Check those numbers vs your bad prop. Also check power to and from fuel governing check switch, mech/norm switch, also synchrophaser disarming in the throttle quadrat. A loose wire from any of those switches will prevent an overspeed when the check switch is hit. Does the prop act like its in mech gov? You said no droop, but how is throttle anticipation?

  7. I like seeing everyones inputs. I don\'t put alot of stock in pressurized dip stick. The current tech data tells you to check both, which is redundant. It was someones answer to a string of prop low oil lights. The propeller servicing is an inexact art. You cant be too sure of how much is in the propeller unless you serviced a dry prop.

×
×
  • Create New...