Gearbox overhaul

by Edgar Teruel in General Tech Discussion 13 years ago

Page 2 of 4

Start
Prev
1
2
3
4
Next
End

Re: Gearbox overhaul

by Harri Lumme » 13 years ago

Harri Lumme

3 18 3

Thanks for checking Roger. I think Rotax should update the service manual. In the current manual the 1000h inspection only applies to the ULS and 600h inspection to the UL without overload clutch.

Harri

Report
Re: Gearbox overhaul

by Roger Lee » 13 years ago

Roger Lee

127 5.2k 4.78k

I agree it should be a little more clear for this instance.

Roger Lee
LSRM-A & Rotax Instructor & Rotax IRC
Tucson, AZ Ryan Airfield (KRYN)
520-349-7056 Cell

Report
Re: Gearbox overhaul

by Roger Lee » 12 years ago

Roger Lee

127 5.2k 4.78k

Okay here's the skinny as they say,

You have to remember that the standard UL engine or the ULS never came with a gearbox slipper clutch before 2003. It was an option. Certified engines S,A and F came with slipper clutches. Then Rotax put the slipper clutch in all the ULS engines after 2003, but still not the UL. So the comments in the Line maint section was really meant to separate the engines with or without a slipper clutch. The language is misleading in the Line Maint manual, but what it should make a little more clear is; the UL or ULS engine without a slipper gets a gearbox inspection after 600 hrs TTSN. If you have a slipper clutch in a UL or ULS then it is 1000 hrs. All Rotax 912 and 914 gearboxes get a gearbox inspect, no exceptions. The language is a little old and the translated message from Germany to English could be a little more clear. You really should get it done as it may find a potential catastrophic problem before it develops.

Roger Lee
LSRM-A & Rotax Instructor & Rotax IRC
Tucson, AZ Ryan Airfield (KRYN)
520-349-7056 Cell

Report
Re: Gearbox overhaul

by Harri Lumme » 12 years ago

Harri Lumme

3 18 3

Hi Roger,

Thankyou for clarifying this. It makes sense but I would have thought that the UL with a lower compression ratio together with a slipper clutch is easier on the gearbox than a ULS and would therefore allow a longer time before inspection, eg. 1200h if not the total TBO. However, I know that you should not try to use common sense when it comes to maintaining airplanes so if Rotax has meant that the inspection is due at 1000h then that is when it should be done.

Thanks and regards,
Harri

Report
Re: Gearbox overhaul

by Harri Lumme » 12 years ago

Harri Lumme

3 18 3

Hi,

The weather warmed up from -30C/-22F to -5C/23F temporarily for a couple of days here in the South of Finland so I was able to get +5C/41F inside the "igloo" to remove the gearbox. It has now been removed and after a bit of cleaning it will be sent to a service centre.

- Should the bearing and seal on the engine gearbox mount be renewed? If yes, is it an easy job or are special tools needed?
- Can the old lock washer on the axle be reused?
- Is it best to renew the thick fuel pump gasket? Is has not been leaking until now but is there a tendency for them to start leaking if reused?

- What are the parts that should be changed in the gearbox itself? My guess is the 3 Belleville washers, propeller shaft bearing and seal? Is there anything else worth changing? The plan is to maintain this engine so that it will run without problems for the next 1000h too.

Thanks and regards,
Harri

Gearboxremovedwithquestions.jpg (You do not have access to download this file.)

enginetentsmall.jpg (You do not have access to download this file.)

Report

Page 2 of 4

Start
Prev
1
2
3
4
Next
End

You do not have permissions to reply to this topic.

Title	Category	Replies
912 Engine propeller gearbox - Interval Operating hours	912 / 914 Technical Questions	6
912 ULS Overhaul TBO	912 / 914 Technical Questions	9
912 gearbox oil mod	912 / 914 Technical Questions	2
Gearbox inspection at 600hr or 1000hr?	912 / 914 Technical Questions	1
Gearbox Problems 912iS	912iS Technical Questions	22

Gearbox overhaul

Recent Videos

Safety First!

ROTALK News

Prize Giveaway!

Log In/Out

Login