(e)
With pliers, remove roll pins.
(f)
Pull fitting from valve body and remove O-ring.
(g)
Clean fitting and apply Dow Coming Lubricant (FS3451) or equivalent to O-ring flange.
(h)
Install new MS29513-019 O-ring. Set fitting in clean area and cover with clear plastic. (Saran wrap, etc.)
(i)
Remove and throw away valve (spring, washer, and spacer.
(j)
Remove and dispose seal (2555-05, Dukes) and O-ring.
(k)
Remove valve from vise. With soft, wood dowel, push out ball from other end of valve body. Be careful not to nick or damage ball. Clean as necessary.
(I)
With roll pin removed from shaft, push control shaft into valve body and remove.
(m)Remove O-ring from shaft and clean O-ring.
(n)
Remove other seal, O-ring, wave washer, and spacer.
(o)
Thoroughlycleaninside of valve and dry.
(p)
Installnewvalve washer and spacer.
(q)
Using Dow Coming Lubricant (FS3451) or equivalent, lubricate one 2559-05 seal and install MS29513-016O-ringon seal.
(r)
Carefully insert seal in body until it meets spacer.
(s)
With control shaftclean and corrosionfree, lubricate with Dow ComingLubricant(FS3451)or equivalent.InstallMS29513-008O-ring.
(t)
Applylargeamountof lubricant on bottom of shaft (28-20-00 Figure301)and install shaft in valve body.
(u)
Replaceroll pins so shaft pin is positioned on side with open designation.Install grooved pins in body with grooved ends down.
(v)
With shaft in closed position, install handle.
(w)
Coat AN500AD6-3 screwthreads with threadlock from kit. Install two AN960C6L washersand screw on shaft. Safety wire handle and screw.
(x)
Installball valve, ensuring ball slides into body with openings toward side of body. Also ensure shaft flange is snug against body flange (28-20-00 Figure 301).
(y)
Install second seal per steps (q) and (r) above.
(z)
Installother new spacer and washer.
(aa) With fitting prepared per steps (g) and (h), install it on valve body with attachingscrews, ensuring threads are coated with Loctite.
EFFECTIVITY:
28-20-00 PAGE
Jan 10/90
PIPER AIRCRAFT
PA-42-720 (Advanced Trainer)
MAINTENANCE MANUAL
A. Distribution (continued)
"On" Position
"Closed" 'Open" Position Position
Shut Off Valve (See Note)
Dukes Fuel Valve (CrossfeedandShutoff) Figure 301
Jan 10/90 28-20-00 EFFECTIVITY: 040-999
PIPERAIRCRAFT
PA-42-720 (Advanced Trainer)
MAINTENANCEMANUAL
A. Distribution(continued)
4. ServicingJet Scavenger Pump (refer to 28-20-00 Figure 302)
This jet pump canister is basically a replaceable, not a repairable item. However, if the jet, elbow, or check valve become clogged or fouled, removeand replace as follows:
(a)
Disconnectinlet line from elbow.
(b)
Releaselocknut securing elbow in position.
(c)
Carefullyremoveelbow, check valve, and replace O-ring if necessary.
(d)
Slide a piece of 0.02 inch safety wire through elbow end of canister to other side and put a 1/16 inch or less bend at end of wire.
(e)
Carefullyslide wire back through and pull out jet and spring washer. Replace washer, if necessary.
(f)
Replaceparts in reverse order.
Line Connector to Solenoid Valve
Hose to Fuel Divider
SpringClamp
Spring Clamp 7 Modified Elbow
Overflow Drain Line Nozzle
Scavenage Can O-RingSeal
Drain Check Valve
Jet Scavenger Pump
Figure 302
EFFECTIVITY:
040-999
28-20-00 Jan 10/90
PIPERAIRCRAFT
PA-42-720(Advanced Trainer)
MAINTENANCEMANUAL
A. Distribution(continued)
5. Removalof Fuel Valves
(a) Ensurecrossfeedvalveis off when removingeitherof the two shutoff valves. Proceedas follows:
(1.) Drain all fuelfrom side of system affected.
(2.) Remove bottomwingroot panel to gain accesstovalve on forward spar reinforcement plate.
(3.) Disconnect lines from valve. Cap lines and remove valve by unscrewing screwsfrom self locking nuts. Disconnectcontrol cable fromactuatingarm.
(b) Toremovecrossfeedvalve, drain fuel from both systems. In left root cavity in front of fuel pump, disconnect valvefromits bracket, tee fitting, and crossfeed line.
6. Installationof Fuel Valves
(a)
Place valve in proper position. Secure to mounting bracketor with attachment clamps, dependingon valve beinginstalled.
(b)
Connectproper fuel lines to valve. Connectcontrol cable to actuator arm with attaching hardware.
(c)
Checkvalve and end fittings for leaks by filling tank with fuel.
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