1). Be sure you check the end play on the strut ass'y where it bolts to the
airframe. Often those shims are left out or its never checked after years of
service. I think max play is .015 (check the MM to be sure) and you use up to
two 100951S016YP washers per side to shim the play out of it.
2). Replace the laminated shim that goes under the top "cap", peeling
each layer off until it fits freely. See MM. Those shims don't last that long
and should be replaced and the strut/top cap play eliminated whenever the strut
is disassembled.
3). If the felt pad is in good shape, there is no need to replace it. If you do
replace it, you may need to trim it. Also, do not "over-soak" it in
SAE 10 oil or it will swell up so much you'll never get the piston into the
strut.
4). Get a hose that will fit over the Schrader valve threads snug enough, and
dip the other end into a gallon jug half-full of 5606 for the servicing part.
That's really the best and quickest way to service a newly OH'd (dry) strut.
Have your ass't hold the jug while you actuate the strut slowly, stop to stop,
until its sufficiently filled. Sufficiently filled on the later model nose gear
is the piston fully compressed to the stop after 3-5 full travels of the strut.
Earlier models called for compressing the strut to within a 1/2 or 1/4 in. of
fully compressed before calling it good, IIRC. Remove the hose while the strut
is compressed. Then you can relax. Put the valve core back in and put shop air
in the strut until you can get the plane on the ground and service it the rest
of the way with nitrogen.
5). Make sure you don't accidently bolt the steering "collar" to the
strut with the zerk on it pointing up, as you won't be able to grease it. It can
swivel 180 degrees while its disassembled without you noticing it. Seems like
I've seen that alot lately on some new customer's airplanes. Make sure that
steering stop "cone" rolls freely on the end of that bolt, too.
Here is another piece of guidance for nose strut rebuilding from Beech Talker
Larry M.
With the
plane on jacks, remove the nose gear. When you disconnect the steering yoke,
careful for the tiny spacing bushings that fall out, get lost. These are very
important. Carefully bleed pressure from the Schrader valve, remove the valve,
replace the O ring under it.
Drain 5606 fluid. Remove tire and wheel from axle. Remove lock ring at top.
Disconnect NG torque knee. Be systematic in disassembly, carefully store parts
to help you with reassembly. When cylinder is open reach in lower portion and
remove oil soaked felt, and place in solvent to clean. Have your new O rings
(Performance Aero) ready, and greased with #5. Make yourself an O ring pick
from a brazing rod, sharpened on the ends. Bend one end at a 45 degree angle,
the other about 120 degrees. Shine your light into the tube, locate the old O
ring, stab it with your pick, and work it out of the groove. Be prepared with
two 3/4" dowels, about 2' long. Place the new O ring on one dowel, insert into
tube, from the other end, insert other dowel. Now you can work the new O ring
into the groove, and push it fully into place.
Clean and
examine scraper, install other easy O ring, wash the felt and re oil it. Your
maintenance manual will give you wear allowances for you to measure with a
micrometer. If you have no excessive wear, you can reassemble. Reinstall, add
new 5606 to a collapsed strut, work it up and down for bubble removal, check
level to full with a 1/4" block at bottom. New valve core, inflate with
nitrogen to about 125 lbs, adjust later to proper height as shown on your
strut decal.
Delta
strut, now owned by Lawson Barber of Fresno CA. does this work exclusively.
559-908-2957 You should have a licensed IA check your work, and sign it off,
if you do it yourself. Not something to be dismissed lightly.
While you
are in there, check the magnesium strut delta for corrosion. Water gets into
the vents in the front, and bimetal action takes place. Some of those parts
are dissolved like an Alka Seltzer tablet. Prevent that by making a curved
aluminum cover for the vents in front. ABS has details.
Another popular strut repair/rebuilding source is Delta Strut, the company
previously owned by Arky Fulk.
Here is Jamey C.'s pirep on them:
Delta Strut (formerly Arky's operation to my knowledge) is now owned by
Lawson Barber (former owner of Barber Aviation) in Madera, CA. He's
located in the hangar next to Barber Aviation (now owned by Chris Tharp).
Apparently Arky retired and Lawson needed a business to pseudo-retire to that
didn't involve standing on his head under instrument panels, laying on cold
concrete floors, etc.
If you aren't familiar with Lawson as an A&P he's a very Beech-savvy guy and
a very nice/fair individual who would be more than happy to help with your strut
issues. I don't know Delta Strut's contact info in Madera but call Judy at
Barber (559) 675-0183) and she'll get you in touch with Lawson.
Delta Strut LLC
1263 E Downing St.
Mesa, AZ 85203
Phone: 480-844-1004
Fax: 480-844-1095 |
Here is a find by BeechTalker John K. Can you tell the difference between
these two PN: 504270 strut seal parts? I didn't think so!
The one on the left is a Beechcraft sourced part at $20 and the one on the
right is sourced HERE
at $7!
Are you shocked by the high cost of Strut "Felt Wiper" from HBC?
Well here is a find from Beech Lister Bob N. to solve that dilemma in CSOB
style:
From W.W Grainger :
Felt Sheet, F3,1/4 In Thick,12 x 12 In
Item # 2FHG2, $16.41
General Purpose, Wool Felt, Backing Type Plain
Thickness 1/4 In, Width 12 In, Length 12 In, F3 Grade, Gray Color, Density 4
Lbs/Sq Yd
or
Felt Sheet, F1,1/4 In Thick,12 x 12 In
Item # 2DAH9, $22.75 ea.
General Purpose, Wool Felt, Backing Type Plain
Thickness 1/4 In, Width 12 In, Length 12 In, F1 Grade, Off White Color,
Density 4 Lbs/Sq Yd.
F1 and F3 refer to the SAE grade, F1 is the highest. Both are indicated for
wiping applications.
They also have it in 24"x24" sheets.
Or, if your nose strut is completely trashed from corrosion, check out
Cygnet's replacement
strut
Cygnet Aerospace Corp.
P. O. Box 6603, Los Osos, CA 93412
(805) 528-AERO (2376) | fax (805) 528-2377
sales@cygnet.aero
Strut
Repair & Overhaul Resources
