Rotax 912 oil tank crush washer.

[facthunter]

Is it really Necessary?  The faster the oil drains, the better. How can  the Original fail?   I'd consider putting a Magnet in it, to catch ferrous metal bits,  Nev

[skippydiesel]

24 minutes ago, 440032 said:

Plan B.

Fit a FUMOTO oil drain valve, once.

I see this idea promoted quiet a lot on the Rotax Owners Forum.

 

Cant see the need myself. At the rate I accumulate hr's  an oil drain only happens once per annum, in a good year a possible second. Hardly a challenging workload.

 

The drain plug should not be tightened any more than necessary to crush the washer (Rotax will have some ridiculously low torque setting , wrist "click" will do me)- easy to see & do. The plug is then safety wired to the base of the tank. - no chance of comming undone.(I have never had a leak from the oil tank).

 

Removal is a doddle - remove safety wire and using two spanners "crack" the lightly torqued plug.

Its now finger tight but a tad hot to actually use the fingers, so continie to loosen with one spanner.

Put your old oil receiveal container up as close to the bottom of the tank, as is constant with doing the job/access - this will reduce the chances of spillage.

I use roofers soft aluminium flashing (Bunnings Aerospace) formed into a  channel & hooked over the engine frame, to direct the oil into a calibrated container (I like to record oil quantity removed, then added).

It's annoying but of little concern if the plug drops into the hot oil - magnet will fish it out.

 

I am not against the oil drain valve - have one fitted to my Ranger sump. The Ranger requires removal of bash plates, before loosening the drain plug and then the position of the drain means oil hits a cross chassis member & splashes everywhere (nasty!). The drain valve & short hose prevents, all that mess & the need to remove bash plates-  a no brainer!😈

[danny_galaga]

Skippy, I thought I'd kill two birds with one stone with my first oil change. I got a disposable aluminium BBQ drip tray thing and bent it to shape to fit under the tank. I taped it in place. That oil shot out so fast it came loose and splashed everywhere 😄

 

"Oh Mr Hart, what a mess!" 

 

So I had to manhandle this hot, rapidly filling tray onto the ground and just let the oil pour into the bottom cowling. Next time, I will use some scrap cardboard (or flashing like you) and just leave the tray on the ground and the flashing sitting, WIRED securely to the bottom of the cowl.

 

Facthunter, there is a magnet near the gearbox, presumably since most ferrous metals will emanate from there. There were some tiny bits on there.

 

😇

Edited Friday at 09:20 AM by danny_galaga

[skippydiesel]

13 hours ago, 440032 said:

Plan B.

Fit a FUMOTO oil drain valve, once.

I see this idea promoted quiet a lot on the Rotax Owners Forum.

 

Cant see the need myself. At the rate I accumulate hr's  an oil drain only happens once per annum, in a good year a possible second. Hardly a challenging workload.

 

The drain plug should not be tightened any more than necessary to crush the washer (Rotax will have some ridiculously low torque setting , wrist "click" will do me)- easy to see & do. The plug is then safety wired to the base of the tank. - no chance of comming undone.(I have never had a leak from the oil tank).

 

Removal is a doddle - remove safety wire and using two spanners "crack" the lightly torqued plug.

Its now finger tight but a tad hot to actually use the fingers, so continie to loosen with one spanner.

Put your old oil receiveal container up as close to the bottom of the tank, as is constant with doing the job/access - this will reduce the chances of spillage.

I use roofers soft aluminium flashing (Bunnings Aerospace) formed into a  channel & hooked over the engine frame, to direct the oil into a calibrated container (I like to record oil quantity removed, then added).

It's annoying but of little concern if the plug drops into the hot oil - magnet will fish it out.

 

I am not against the oil drain valve - have one fitted to my Ranger sump. The Ranger requires removal of bash plates, before loosening the drain plug and then the position of the drain means oil hits a cross chassis member & splashes everywhere (nasty!). The drain valve & short hose prevents, all that mess & the need to remove bash plates-  a no brainer!😈

[danny_galaga]

Well, finally put the plane back together. Took my time on it. But THREE times I was interrupted by people coming in to have a chat. I was very careful about what it was I was doing so that I continued where I left off without missing anything. However, where I disappointed myself was being in a rush to do a circuit after starting it and rechecking the oil level. It was getting a little late and I ended up not doing a complete preflight check, it was just luck id even taken the pitot cover off! 

 

I survived, but clearly I wasn't in the right frame of mind to be flying, let alone a flight test. If there was an emergency in that frame of mind, would I have handled it well?

 

If I get in a similar situation again, I'll be sure to just pack up and come back another day. It's not like there's any schedule to get somewhere. 

[sfGnome]

You’ve just mover a shovel full from your bucket of luck into your bucket of experience. Thanks for putting this out there. It’s really important that we learn from each other. 

[onetrack]

I knew people who were missionaries in PNG. Their whole family took a flight on a twin piston aircraft to travel to an outlying mission from Port Moresby. On the way, one engine caught fire in a big way, and the aircraft crashed, with the loss of all on board.

The crash investigators found the cause was a fuel line to one of the engines that wasn't properly tightened. The LAME in Port Moresby had connected the line finger tight, then got called away from the job, with an important phone call.

When he returned to the job, he thought he'd fully tightened the fuel line, and cleared the the aircraft for flight, and sent it on its way - and sent all the people in it, to their deaths.

 

Edited yesterday at 12:50 AM by onetrack

[danny_galaga]

12 minutes ago, onetrack said:

I knew people who were missionaries in PNG. Their whole family took a flight on a twin piston aircraft to travel to an outlying mission from Port Moresby. On the way, one engine caught fire in a big way, and the aircraft crashed, with the loss of all on board.

The crash investigators found the cause was a fuel line to one of the engines that wasn't properly tightened. The LAME in Port Moresby had connected the line finger tight, then got called away from the job, with an important phone call.

When he returned to the job, he thought he'd fully tightened the fuel line, and cleared the the aircraft for flight, and sent it on its way - and sent all the people in it, to their deaths.

 

Something like that happened in Australia in the fifties. Small airliner of some sort. The mechanic got called away for a phone call and had an argument with his wife. He forgot to finish what he was doing and the plane crashed. I think it might have been Australias largest crash. They mandated new procedures after that to help eliminate those sorts of situations. I read about it in the flight safety magazine we'd get in the 90s. 

 

I bore that in mind while working on the engine. For instance, masking tape over the ignition switch saying NO OIL IN ENGINE.

 

But then it a went out the window once the headphones were on.

[facthunter]

That was an ANSETT DC4 out of Perth Fuel system issue.. Tell people to go away when you're doing important things and IF you HAVE to Leave Make a NOTE to your self about where you were at. Shift changes have been found to be an obvious potentially dangerous disconnect   Tag things.  Nev

[facthunter]

Self discipline makes old Pilots possible. Nev

[onetrack]

The 1950 crash of the DC-4 Amana, just outside York in W.A. was Australia's worst air disaster up to that time. All 29 on board were killed when the Amana lost power to possibly more than one engine, and crashed into heavily timbered country populated with large whitegum trees.

The cause of the crash was investigated and examined in great detail, and many tests were carried out. No cause could be firmly ascertained for the crash, but water and corrosion by-products entering the engines carburettors were high on the list of causes.

Months after the official investigation ended, stories began to circulate about the one gallon container used to check for water in the aircrafts fuel filters, that was found empty and blown over on the runway. The container was  found during the investigation, and airline and airport staff were questioned over it, but the questioning was short, and the line of investigation was rapidly terminated.

 

But the rumours were that the LAME who was using the container to check for water, opened a drain cock in the cross-feed line between tanks - and was then called away to a phone call from his wife.

The rumour mill ran that the drain cock was left open by the LAME, and upon the crew selecting different tanks in flight, the open drain cock allowed air to enter the engines fuel system, and the engines started starving of fuel.

 

The supposition was dismissed as highly unlikely, because it was presumed the crew would never change the fuel selection valve so early in the flight.

In the final washup, no major definitive reason was ever decided on, as to the cause of the crash - but the corrosion by-products found in the fuel lines and carburettors, were almost certainly one of the causes of the crash.

Contributing causes would have been initial power loss, as at least one of the engines initially faltered, low altitude soon after leaving Perth, associated with a full load of passengers and freight and engine power loss, and high altitude country of the Darling Scarp, that aircraft must climb over, to head East from Perth.

 

https://en.wikipedia.org/wiki/1950_Australian_National_Airways_Douglas_DC-4_crash

 

 

Edited yesterday at 02:29 AM by onetrack