H36 Master Cylinder http://www.aircraftspruce.com/catalog/lgpages/cleve_mbrakecyl3.php
H36 Wheels and Brakes http://www.aircraftspruce.com/catalog/lgpages/cleve_amphibian.php?recfer=7984 regards Rob Rob Thompson 0429 493 828 (Please note that my new email address is [email protected]) On Mon, Jun 25, 2018 at 8:48 AM, Michael Stockhill <[email protected]> wrote: > I just checked my H36/HK36 pplservice manual. Page 59 specifies that DOT3 > or some equivalents are used. They emphatically state that MIL5606 is not > to be used. I have always attributed this to the belief that the seals and > O rings in the master cylinder were incompatible with 5606. If the master > cylinder is a Cleveland part, I wonder if anyone has a Cleveland part > number. I have always thought of it as a BMW part--like the gas cap. > > Other serial number birds may have differing specifications in their > service manuals. > > I have no clue why Hoffman chose DOT3 fluid, but I can't imagine any such > manufacturer buying Cleveland brakes and then disassembling them to change > out O rings due to an incompatibility issue. Nor, I wonder if Cleveland > would make such a change on the assembly line, for certification reasons. > > My H36 arrived with automotive brake fluid. I put new tires on and rebuilt > the brakes, operated without any issues for about fifteen years, then > rebuilt the brakes a year or so back when I installed new tires. Upon > disassembly this was purely preventive maintenance because I hate the drill > of removing the wheels from the fairings. In both instances of disassembly > I used MS O rings. I saw no softening or significant deterioration after > years with DOT3. > > I live in a fairly dry climate, so absorption of water doesn't seem an > issue for either the H36 or thousands of autos here. > > My sophomoric understanding of hydraulics tells me the issue of water in > brake fluid is that it changes into a vaporous state at about 100 degrees > C. As with brake fluid, it is not compressable in fluid state. If the > brakes get hot--above that temperature and there is moisture in the slave > cylinders or in adjacent lines, one could have soft brakes or even > failure. In comparison, corrosion may be the lesser concern. > > The fluid in the brake system does not circulate, so I wonder if it > wouldn't take many months of water absorption before the fluid at the slave > end of the system had an issue. This may be the case with most autos in the > states that can go decades without brake fluid replacement. It is a rare > spot of maintenance here (we have our foibles, including our elections.) > Once, when I requested brake fluid change, the shop didn't even get the > reason. > > Michael Stockhill > Polson MT > > > On Jun 24, 2018 3:25 PM, "Rob Thompson" <[email protected]> wrote: > > I just found this useful and comprehensive table of how different rubbers > are effected by different chemicals http://mykin.com/rubber- > chemical-resistance-chart-3 > It says that Nitrile rubber is OK with glycol.... but as the auto brake > fluid absorbs water over time it must adversely effect the Nitrile O rings > as Nigel says. With Nigel's experience in hydraulics I would take what he > says as being the most practically accurate. > I have always bought genuine Cleveland nitrile rubber 0-rings for the the > H36 brake system and used the mineral oil that is recommended for them. You > need to pump a lot through to get the bubbles out so the mineral oil saves > a fair bit of cash. You can use Automatic Transmission Fluid. > Sounds like Glycol based fluids may be OK but on the condition that you > need to change them regularly if you have genuine Cleveland seals. > And make sure no one gets them mixed up when topping up the system! > > Rob > > > regards > Rob > > Rob Thompson > 0429 493 828 > (Please note that my new email address is [email protected]) > > On Sun, Jun 24, 2018 at 10:05 PM, Nigel Baker <[email protected]> > wrote: > >> I think your right on the DOT 5 Konrad. Silicone lubricants are fine on >> BN seals and Silicone Grease is used to lube BN seals in food processing >> machinery as it is non toxic so compatible. >> >> The H36 mm does say DOT fluid but either some have been changed over at >> some stage eg by the Thai Airforce and others or depends on when it was >> built. There is a mix out there that I have seen. >> >> >> >> *Characteristics of common braking fluids*[6] >> <https://en.wikipedia.org/wiki/Brake_fluid#cite_note-DOT-6>[5] >> <https://en.wikipedia.org/wiki/Brake_fluid#cite_note-epic-5> >> >> *Dry boiling point <https://en.wikipedia.org/wiki/Boiling_point>* >> >> *Wet boiling point* >> >> *Viscosity limit* >> >> *Primary constituent* >> >> DOT 2 >> <https://en.wikipedia.org/w/index.php?title=DOT_2&action=edit&redlink=1> >> >> 190 °C (374 °F) >> >> 140 °C (284 °F) >> >> ? >> >> castor oil/alcohol >> >> DOT 3 <https://en.wikipedia.org/wiki/DOT_3> >> >> 205 °C (401 °F) >> >> 140 °C (284 °F) >> >> 1500 mm2/s >> >> glycol ether <https://en.wikipedia.org/wiki/Glycol_ethers> >> >> DOT 4 <https://en.wikipedia.org/wiki/DOT_4> >> >> 230 °C (446 °F) >> >> 155 °C (311 °F) >> >> 1800 mm2/s >> >> glycol ether/borate ester >> <https://en.wikipedia.org/wiki/Borate#Borate_esters> >> >> LHM+ >> <https://en.wikipedia.org/wiki/Hydropneumatic_suspension#LHS_versus_LHM> >> >> 249 °C (480 °F) >> >> 249 °C (480 °F) >> >> 1200 mm2/s [7] <https://en.wikipedia.org/wiki/Brake_fluid#cite_note-7> >> >> mineral oil >> >> DOT 5 <https://en.wikipedia.org/wiki/DOT_5> >> >> 260 °C (500 °F) >> >> 180 °C (356 °F) >> >> 900 mm2/s >> >> silicone >> >> DOT 5.1 <https://en.wikipedia.org/wiki/DOT_5.1> >> >> 260 °C (500 °F) >> >> 180 °C (356 °F) >> >> 900 mm2/s >> >> glycol ether/borate ester >> >> *Wet boiling point defined as 3.7% water by volume.* >> >> I have just looked up Matco and yep can use DOT 5 but not 5.1 so same >> with the other DOT series fluids. Same chemical problem. >> >> http://www.matcomfg.com/MASTERCYLINDERCAP10MC4X-idv-3835-5.html >> >> Thus Diamond must change the seals or they get them special order. Same >> problem exists with Cleveland. >> >> >> >> Cheers. >> >> Nige. >> >> >> >> >> >> >> >> *From:* [email protected] <[email protected]> *On >> Behalf Of *Konrad FDU >> *Sent:* Sunday, June 24, 2018 8:57 PM >> *To:* [email protected] >> *Subject:* AW: [DOG mailing list] NO AUTOMOTIVE BRAKE FLUID IN H36 >> >> >> >> Hello Rob, >> >> >> >> my MM for the Super Dimona specifies DOT4 as break fluid. So does TOST >> which also is a Cleveland break. It is not specify DOT 5 that you might >> refer to and is silicone based (not DOT5.1 which again is glycol based) . >> >> I would not call DOT4 or DOT3 water soluble. It is hygroscopic and >> accepts to accumulate the humidity from the air but water degrades >> performance and boiling point. This is why break fluid is changed regularly >> or checked for water. >> >> >> >> regards >> >> Konrad >> >> >> ------------------------------ >> >> *Von:* [email protected] [mailto:[email protected] >> <[email protected]>] *Im Auftrag von *Rob Thompson >> *Gesendet:* Sonntag, 24. Juni 2018 11:59 >> *An:* [email protected] >> *Betreff:* Re: [DOG mailing list] NO AUTOMOTIVE BRAKE FLUID IN H36 >> >> Hi Michael, >> >> So you have been running water soluble auto fluid in Cleveland brakes for >> 17 years? >> >> Interesting. I didn't think the rubber bits would go OK with a >> water/glycol based fluid. >> >> Make sure you label the reservoir very clearly what type you are using. >> If someone adds the wrong type you will get a horrible mess! >> >> >> regards >> >> Rob >> >> >> >> Rob Thompson >> >> 0429 493 828 >> >> (Please note that my new email address is [email protected]) >> >> >> >> On Sun, Jun 24, 2018 at 9:26 AM, Michael Stockhill <[email protected]> >> wrote: >> >> I believe the service manual specifies automotive type fluid, likely for >> the motorcycle type master cylinder. No problem with Cleveland O rings in >> slaves for last 17 years. >> >> >> >> Best >> >> >> >> Michael Stockhill >> >> >> >> >> >> >> >> >> >> >> >> On Jun 23, 2018 3:01 PM, "Rob Thompson" <[email protected]> wrote: >> >> Just a reminder to everyone and Martin from K1W1 land. >> >> The H36 uses hydraulic brake fluid. Auto fluid is water based and will >> wreck the seals and system. >> >> >> >> regards >> >> Rob >> >> >> >> Rob Thompson >> >> 0429 493 828 >> >> (Please note that my new email address is [email protected]) >> >> >> >> >> > > >
