Rotax Oil Injection Bottle Bracket Cracking

SamL · 14-04-2008, 04:51 PM

My gyro is fitted with a Model 99 582 Rotax. This one is fitted with an oil injection (pump) system.
The engine has only done about 140 hours and has already broken 2 mounting brakets.

The last one I had guseted to strengthen it and still it has broken through.
I am having this latest one fully guseted on both sides and will then cross my fingers.

I have spoken to Rotax who are wipeing there hands of this problem.

I do know of several Trikes with the same problem.
Is anyone else having the same problems?????

Regards Sam...

niquenaque · 14-04-2008, 05:35 PM

Sam,

Why not remote the bottle onto the mast to save you the anguish?

You'd need a oil resist flexible hose for the connection - see Enzed or similar for a solution there.

Hope this helps,

Nic.

rotor · 14-04-2008, 05:50 PM

Saw radiators rubber mounted to a 582 that had the same trouble ... seems they have a lot of vibration ... not sure how you'd fix the problem other than mounting it remotely as Nique said - it appears to be a fairly weighty/bulky little item to hang out there - I can see why it has that problem ...

SamL · 14-04-2008, 11:44 PM

The silly thing is that it is made from Stainless Steel. Then it is both punched and folded. The bracketing system is made up of 2 brackets. 1 upper and 1 lower. Its the upper one that keeps brakeing.
I will take some photos of an earlier cracking bracket, and the failed guseted bracket as soon as I can.
Failing this brand new fully gusetted bracket, I will re-engineer it using mild steel.
Keep you posted.
SamL

disco · 15-04-2008, 08:57 AM

Sam the exhaust on your gyro looks awesome. Mine's got springs and the paint flakes off from the heat.

what paint are you using? and what's the go with those clamps where the springs are on mine?

Mitch · 15-04-2008, 12:43 PM

Dean,

You can get them from CPS (California Power Systems ?) USA.
I believe they are called Exhaust Ball Joint Brackets.

They cost approx $35USD per bracket joint.

They are brilliant!

Hoops on the exhaust get ground off (not needed).

Mitch.

SamL · 15-04-2008, 10:17 PM

Quote:

Originally Posted by Mitch

Dean,

You can get them from CPS (California Power Systems ?) USA.
I believe they are called Exhaust Ball Joint Brackets.

They cost approx $35USD per bracket joint.

They are brilliant!

Hoops on the exhaust get ground off (not needed).

Mitch.

They are Brilliant aren't they Mitch, Butterfly is looking good their mate

SamL · 15-04-2008, 10:33 PM

Back to this silly

bracket.

I took some pictures today. Bracket on its own is the second one which started cracking. I have circle highlighted the starting hairline cracks. I also have the current pictures of number one fitted with gussets and cracked in 4 spots.
This one origionaly had small hairline cracks when I had it gusseted.
Number 3 is currently now being welded and brand new with full length gussets.
My engine runs like a dream and I have spent lots of time balancing it, so there should be no reason for this to crack other than poor Rotax design engineering.
This is a real problem, and if not checked could cause full seperation of the upper mounting bracket. This failure could cause the oil filled bottle to fall onto the hot exhuast below, or even break and fly through the prop.
The concequences are apparent and should be taken very seriously by all owner operators.

In my opinion an A.D. should be circulated and Rotax be made to do something about it, before someone gets hurt or worst!!!!!!!!

SamL..............

niquenaque · 16-04-2008, 12:03 AM

Sam,

Why not start one now?

We hereby disown the aforesaid bracket and demand its replacement - chuck it on the AOPA web site and see rotax 5hit themselves... Complain ferociously to the local agent, if it is an issue that is a safety thing and we issue an official ASRA AD on them and send it on to the SAAA, RAA, AUF and CASA, I think Rotax will begin to do something about it, they most likely need a boot up the behind to get them moving on this issue.

Have you tried annealing the stainless after delivery to you? I know Rotax should do this but they most likely don't. You'll note that it starts cracking in the first mm of the steel first, bit like what I've said prior about machineing defects eating into the mm away from the machined surface - don't do it to alloy!

Peak revs on your machine are around 7k and the cruise I'm guessing is 5k.. hell of a lot of cycles for a little steel bracket holding up a bottle.

Could you put longer bolts in and put some rubber mounts either side of the bracket to kill off some of the cycles to mitigate the issue? Its the only way I can see you reducing the effect short of my prior recommendation.

Cheers,

Nic.

Gyrodes · 16-04-2008, 11:17 PM

Sam,
For what it is worth you need a brace from the upper two bolts with the ordinary nuts and the nyloc's down to the two rubber mounts at the bottom, fallowing the contour of the plastic tank. Make sure you have the metal to metal contact. This would give you triangulation support on that bend. I have observed plastic and metal doing the exact same in other applications. I did exactly the above and it no breaky after 15 years on the rig. Now those down the hole hammers try every thing out especialy welding done with migs. I find that DC stick is the only welds to hold up in that application. The bracing you show in the picy is not the answer as it will still have a high flex point.
I would say that the flexing is in the vertical direction, the brace will help support it.
Cheers, hope this helps. Des Garvin