Today's Message Index:
----------------------
1. 12:48 AM - Re: 912 gearbox problems?? (John Gilpin)
2. 05:59 AM - Re: 912 gearbox problems?? (Thom Riddle)
3. 12:49 PM - Re: 912 gearbox problems?? (Roger Lee)
Message 1
INDEX | Back to Main INDEX |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: 912 gearbox problems?? |
So the lead causes the clutch to lock up rather than slip easier.
If a torque check on the friction clutch is right on spec, does that
mean that any lead that might be present isn=99t really a
problem??
JG
Message 2
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: 912 gearbox problems?? |
Roger is spot on regarding lead buildup in the gearbox slipper clutch. A couple
years ago, I did a gearbox inspection on the Diamond Katana which I am now part
owner. The type certificated Rotax engines, in this case 912-F3, all use the
slipper clutch in the gearbox, even the 80 hp ones like in the Katana. Before
I bought into the airplane it had been flown exclusively on 100LL for its 1000+
hours at the time of its first gearbox inspection (yes, way overdue).
The gearbox was in fine shape except for the slipper clutch which I sent to Lockwood
Aviation for cleaning and inspection. They told me they had never seen a
clutch so badly gummed up with lead as this one was. It has been back in service
now for more than a year and we did the auto-fuel SB to allow us to fly the
Katana with E10 of 87 octane (80 hp engine).
I burn 87 AKI E10 during most of the year when flying regularly but when winter
comes I fill the tank with 100LL and end up using less than one full tank of
100LL/yr because the winter wx here does not allow much flying. Because this is
a type certificated engine/airplane, fuel additives like Decalin or Stabil are
not permitted. If Stabil were permitted I'd keep auto-fuel in the tank all
year, with Stabil added for winter, and use 100LL only when traveling where auto-fuel
is not available. I use 100LL in the winter, when it is rarely flown,
because it does not deteriorate quickly like auto-fuel does. But I do use Formula
Shell semi-synthetic oil which is on Rotax's list of approved oils.
--------
Thom Riddle
Buffalo, NY (9G0)
Kolb Slingshot SS-021
no engine
FOR SALE
Diamond Katana DA20-A1
Rotax 912 F3
Don't worry about old age... it doesn't last very long.
- Anonymous
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=394799#394799
Message 3
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: 912 gearbox problems?? |
Lead will not lube anything in our engine and it will gum up the slipper clutch
and leave deposits all over. When you do a friction torque test on the gearbox
it has nothing to do with the clutch itself. It is only testing the amount of
pressure the Bellville washers are exerting on the dog gear set. Typically the
higher the test numbers the better. Average is usually 440-485 in/lbs.
If you can stay away from 100LL as much as possible you are way ahead of the extra
maint. cost and time involved. The other problem is most owners don't maint.
their engine enough or read the manual so by the time lead is a real problem
it has done its damage. 100LL users must change oil more often (25 hrs) and
they have shorter maint. time schedules for other components compared to 91 Oct.
users.
100LL is a costly fuel in more ways than one.
--------
Roger Lee
Tucson, Az.
Light Sport Repairman - Maintenance Rated
Rotax Repair Center - Heavy Maint. Rated
Home 520-574-1080 TRY HOME FIRST
Cell 520-349-7056
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=394831#394831
Other Matronics Email List Services
These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.
-- Please support this service by making your Contribution today! --
|