There are snap rings retaining the bearings that will require removal of
everything as an assembly.

On Mon, Aug 17, 2015 at 7:49 AM, Michael Stockhill <[email protected]> wrote:

> Guy,
>
> You will need to remove the brake assembly/spacer etc  to remove the wheel
> and tire and to replace or service the bearing.
>
> MLS
>
> On Mon, Aug 17, 2015 at 5:51 AM, Guy Audenaerde <[email protected]>
> wrote:
>
>> I found a more detailed drawing of the wheelassembly, i think this might
>> help, unfortunately the left side is not completely in the picture...
>> I did not loosen or remove the bolts holding the brakeassembly to the
>> wheelfairing, but read in the mails that this is compulsory for good result.
>> Is it necessary to remove the brakeassembly in order to get the wheel out
>> of the fairing once the axle is removed?
>> I was thinking to combine the special  extracting tool with the CO2
>> method.
>> I was told to heat the axle from the inside with a very mild flame to
>> about 60 degrees celsius and let the warmth soak into the outer spacertubes
>> during 20 minutes.
>> Once these spacertubes are warm ( and expanded ) one should rapidly cool
>> the axle with Co2 or other cooling gas/liquid in order to make it shrink in
>> diameter, thus freeing it from the
>> expanded outer spacertubes.
>> I start work on the extractor-tool,
>> Guy
>>
>>
>> *-------Oorspronkelijk bericht-------*
>>
>> *Van:* salto <[email protected]>
>> *Datum:* 17/08/2015 5:33:46
>> *Aan:* [email protected]
>> *Onderwerp:* RE: [DOG mailing list] Removing wheel axle
>>
>>
>> When overhauling the wheel bearings of my H-36 some years ago I found
>> that the bearing seals were totally ineffective.   The Cessna felt seal and
>> support washers were in place but the internal diameter of the seal was
>> 0.125” larger than the steel collar on which it was supposed to bear, thus
>> leaving an air gap all the way around the bearing where water, dust & mud
>> could enter.   This clearance was undoubtedly the cause of our bearing
>> failures, especially in Australia’s dusty airfield environment.  Hoffman
>> were not interested in this problem so we solved it by removing the Cessna
>> felt seal and alloy washers and substituting a neoprene  automotive seal
>> with the same outer diameter but with a smaller internal diameter which
>> matched the steel collar.   The seal is a readily available size & is
>> commonly fitted to trailer & caravan wheel bearing hubs.   Other Australian
>> operators addressed the problem by retaining the original felt seals &
>> washers but replacing the steel collar with a new one machined to the
>> correct outer diameter to fit the original felt seals.   Either approach
>> works quite well, but if you decide to make new collars ensure that you add
>> a small chamfer both sides of the internal bore of the collar to ensure it
>> bears only on the flat bearing faces.
>>
>> Hope this helps
>>
>> J G Viney. Dimona Lisa VH-GVQ
>>
>>
>>
>> *From:* [email protected] [mailto:[email protected]] *On
>> Behalf Of *Michael Stockhill
>> *Sent:* Monday, August 17, 2015 12:58 PM
>> *To:* [email protected]
>> *Subject:* Re: [DOG mailing list] Removing wheel axle
>>
>>
>>
>> Reviewing the H36 parts book that I have, the drawing of the
>> wheel/axle/brake assembly is very small scale, with few callouts for
>> parts.  One thing that is evident is that the axle nut and lock washer are
>> on the outside of the wheel fairing.  In the two aircraft I maintain, both
>> had the axle nuts inboard, with the axle inserted from outboard, resulting
>> in interference of the axle nut and lock washer with at least two of the
>> four attachment bolts that secure the brake mechanism mounts.  While it may
>> be "prettier" to have the axle nuts inboard, it is probably best to go with
>> the configuration shown in the parts book.  In my instance, I thought of
>> reassembly that way, but elected to use the countersunk screws as a minor
>> alteration, which we can do in this country as mechanics if we are brave
>> enough.
>>
>>
>>
>> Besides the four attachment bolts, there are an additional four securing
>> a flange for the floating brake caliper.  On  one or two of the four brakes
>> I worked on, these had to be loosened or removed in order to provide
>> clearance for removing the caliper.  Each caliper is located by two rods of
>> about 7/16 diameter and an inch or so in length.  If the rest of the wheel
>> assembly is corroded, it is probable that these are also corroded.  They
>> can and should be cleaned and polished.  The outer portion of the bore on
>> the cylinders is also likely to show corrosion.  It is a judgement call,
>> but I am usually comfortable with cleaning up that corrosion with
>> Scotchbrite or similar products.  Best to avoid steel wool as particles
>> will embed in the aluminum of the cylinder.  Pistons can similarly be
>> salvaged.  Braking action is significantly improved when this corrosion is
>> cleaned up.
>>
>>
>>
>> Removal of the bearings from their spacers may necessitate fabricating a
>> tool for a press or bearing puller.  If I recall correctly, the ID of the
>> bearings is 31 or 31.5 mm, and the axle is 30 mm diameter. The spacers have
>> a shoulder on them.  A tool would have similar configuration, with an OD of
>> 31 or 31.5 mm, and a shoulder, with an OD of 30 mm.
>>
>>
>>
>> Problematic was getting all the air bubbles out of the brake lines when
>> bleeding them (best done from the bottom).  There is a flexible aircraft
>> hydraulic hose or line downstream of the master cylinder that can trap air
>> bubbles.  Another more gifted Dimona mechanic told me that raising the tail
>> can often cause those bubbles to be displaced.  This worked for me on both
>> aircraft, with the tail raised about three feet or so.
>>
>>
>>
>> Surely clean up any corrosion on the inside of the axles.  And think of
>> the next guy when reassembling, using Boeshield or similar products for
>> corrosion control and maybe antiseize materials.
>>
>>
>>
>> If all else fails in attempting to remove the axles, consider that
>> Lycoming's technique for removing seized sparkplugs is to make a funnel
>> over the sparkplug and chill it with a blast of CO2.  One could probably
>> shoot CO2 through the bore of the axle and shrink it away from the spacers!
>>
>>
>>
>> MLS
>>
>>
>>
>> On Sun, Aug 16, 2015 at 6:00 PM, Michael Stockhill <[email protected]>
>> wrote:
>>
>> A revisionist thought.  If the axle is truly seized, it is likely to be
>> seized on the the sleeve/carrier assembly for the brake caliper as well as
>> the opposing bearing carrier tube.  It may be best to leave it unloosened
>> until the axle has broken free.  Sorry for the poor thinking on my feet
>> today.  I should get out the parts book to refine my terminology.
>>
>>
>>
>>
>>
>> MLS
>>
>>
>>
>> On Sun, Aug 16, 2015 at 5:48 PM, Michael Stockhill <[email protected]>
>> wrote:
>>
>> Yes, those will have to come out eventually.  I would just loosen them
>> until you get the axle out.  I did find during reinstallation that if I
>> tightened them before everything else was assembled, that the axle would
>> bind at insertion.  If anyone else has done brake and tire work on the
>> aircraft previously, you may find that the holes in the brake attach plate
>> have been elongated--it looks like during reassembly someone didn't get
>> proper alignment and just went after them with a drill bit. .  On both of
>> our ships, that was the case. Going to the slightly oversize 1/4 inch
>> countersunk machine screws (vs 6 mm bolts) mitigated that a bit.  Keep
>> track of which brake assembly goes on each side of the ship.
>>
>>
>>
>> Photos tomorrow.  I took advantage of good WX to fly my PIK 20E for a
>> couple hours, and did the shuffle/dance  to drag my Aztec out of the hangar
>> for test flight after maintenance.
>>
>>
>>
>> Cheers,
>>
>>
>>
>> On Sun, Aug 16, 2015 at 5:36 PM, Nils Beck <[email protected]> wrote:
>>
>> Did you also remove the 4 bolts that attach the brake to the wheel
>> fairing?
>>
>> Best regards
>>
>> Nils Beck
>>
>>
>>
>>
>> On 16.08.2015 14:18, Guy Audenaerde wrote:
>>
>> My Dimona H36 Mk2 ser. 36267 build in 1988, equipped with Sauer
>> S2100-1ss1 has 4550 hours on the airframe.
>>
>> It is three years in my ownership and i suspect that the maintenance of
>> the main wheelbearings is urgently due.
>>
>> When i jack up the wheels and rotate the wheels they emit a "grinding"
>> noise and have a lot of play.
>>
>> Question: can someone give me a detailed procedure for removing the axle
>> and overhauling the wheelbearings.
>>
>> I removed the locking nut on the outside of the wheelfairing but did not
>> succeed in getting the axle out of the fairing,
>>
>> despite carefull tapping on the extremities with a hardwooden block.
>>
>> I suspect that the  pipes that hold the bearings in place are froozen on
>> the central axle and prevent this axle of sliding out of the fairings;
>>
>>
>>
>> Awaiting 'instructions'
>>
>> Guy Audenaerde
>>
>>
>>
>>
>>
>>
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150816>
>>
>> *GRATIS animaties voor je e-mail*
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150816>
>>
>> *Klik hier!*
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150816>
>>
>>
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150816>
>>
>>
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150816>
>>
>>
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150816>
>>
>>
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150816>
>>
>>
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150816>
>>
>>
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150816>
>>
>>
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150817>
>>  GRATIS
>> animaties voor je e-mail
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150817>
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150817>
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150817>
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150817>
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150817>
>>  Klik
>> hier!
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150817>
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150817>
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150817>
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150817>
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150817>
>> <http://www.incredimail.com/?id=621163&did=10501&ppd=2842,201206281824,19,1,1&rui=146739762&app_test_id=0&sd=20150817>
>>
>>
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