914 block cracks

[Russ]

Was told yesterday of 2....3 Rotax 914's based caboolture Q, all having cracks in blocks. Might pay any folks here to closely inspect their engines.

 

Seems extremely strange, being those 4bangers are regarded as near on bullit proof.

 

 

[facthunter]

They are different from the 912. You can assume nothing. Nev

 

 

[SDQDI]

Any idea of the hours on them?

 

 

[bexrbetter]

Depends where and what the cracks are. I have seen a number of cracks in blocks and heads on a wide range of vehicles over the years that weren't really critical, more just the parts stress relieving themselves and going no further.

 

Not confidence inspiring I admit but just the way it is sometimes.

 

 

[SDQDI]

Depends where and what the cracks are. I have seen a number of cracks in blocks and heads on a wide range of vehicles over the years that weren't really critical, more just the parts stress relieving themselves and going no further.Not confidence inspiring I admit but just the way it is sometimes.

Yep now you mention it I've known some people who have cracked and they still seem to function not too bad:joystick:

 

 

[Guest ozzie]

Continentals are well known for cracking in various areas. Several ADs on them concerning length and position.

 

 

[planesmaker]

Rotax put out a service bulletin several years ago on it. They must be inspected regularly. It is important for maintenance people to check all current SB's when doing maintenance.

 

Tom

 

 

[planesmaker]

I would like to know what aircraft they are in and how they are operated. Does seem odd they are from the same place.

 

Tom

 

 

[Russ]

$12k for new cases.....yikes. Known problem of a certain production batch.

 

 

[Kyle Communications]

914 are a 912 80HP engine the 912ULS is a different beast

 

Must be in gyros at Ycab...I haven't heard anything about it in planes

 

 

[facthunter]

Most aero engine cases will crack with time in service. ( A FAIR bit of time hopefully) Some particular ones have it happen in the first engine life. There would have to be a design fault or some particular set of circumstances causing it in a low time situation. There should be a claim on the maker, unless some abuse was the issue. As has been said the older 912 (particularly the 80 HP) were super reliable. Nev

 

 

[M61A1]

Yep now you mention it I've known some people who have cracked and they still seem to function not too bad:joystick:

Once they've cracked though....you never completely trust them again.

 

 

[Russ]

Update......Floods have record of serial numbers of problem engines, the "fix" is replace the blocks, no help by Rotax I,m told, .......bit harsh.

 

 

[facthunter]

They charge a top figure for their engines. Proper back-up is not too much to expect from a "quality" company. Nev

 

 

[Downunder]

My 2 year old 912ULS is now under this Service Bulletin for cracks in crankshaft http://www.flyrotax.com/portaldata/5/dokus/d05775.pdf

 

Periodic checking of the crankshaft journal (power take off side) for ROTAX Engine Type 912 and 914 (Serie)

 

Sent me the checking tool free but had to pay postage.

 

Overall, I can't say I'm too impressed at all ....... Paid a premium price, expect a premium engine.

 

Probably devalues it somewhat too......

 

 

[Oscar]

Given the odium heaped on Jabiru engines and customer support by certain forum members over a considerable period and the upholding of Rotax as a gold standard for both, this comes as somewhat of a reality check...

 

 

[microman]

Are we talking about cracks in crankcases or fretting crankcases? - the latter problem has surfaced in quite a number of 912S engines here - as Russ says there was a problem with a batch of engine numbers.

 

 

[facthunter]

Nothing's perfect, even Pratt & Whitney, when it's worked on designed and operated by human beings. Especially when it is a reciprocating piston engine. Nev

 

 

[Russ]

Just maybe.....it,s fretting along the top joint areas, oil seepage is apparent there.

 

( another flyer had just that ) on his 914.

 

 

[Bob Llewellyn]

Given the odium heaped on Jabiru engines and customer support by certain forum members over a considerable period and the upholding of Rotax as a gold standard for both, this comes as somewhat of a reality check...

I'm sure the billet 'cases on the jabiru are not as good as the cast* cases on the 914... everyone knows castings are better than billet

*Rotax use die castings, which inevitably suffer some degree of inclusions and shrinkage stress.

 

Contacoming use sand or permanent mold (glued sand) castings, generally in 355 (Al-Cu); the alloy overages in service, and it's a contest between the alloy getting so soft cracks don't propogate*, and the shrinkage stresses relieving by breaking something. The Jab cases have near twice the yield strength, and don't age at anything like the same rate (ie they retain their properties for longer!).

 

*Instead, the barrels blow off - late 2nd life or 3rd life...

 

Depending upon the location & size, Contacoming cracks are allowed to be welded, using a piss-weak filler; it's a band-aid fix, most of the time. Rudi's mob (at Sale) have a much better weld repair process, but these days CASA couldn't handle extending the approval to Rotii, even if Rudi were willing to have a go (he might be?).

 

$12k for a crankcase? Is it a hand-forged unit for a Merlin? Sand castings run about $11/kg, so the basic casting cost would be about $100; amortising the dies would be about 50 cents; machining would be a few hundred; the rest must be gouging.

 

 

[Oscar]

I'm sure the billet 'cases on the jabiru are not as good as the cast* cases on the 914... everyone knows castings are better than billet *Rotax use die castings, which inevitably suffer some degree of inclusions and shrinkage stress.

Rudi's mob (at Sale) have a much better weld repair process, but these days CASA couldn't handle extending the approval to Rotii, even if Rudi were willing to have a go (he might be?).

From what I hear, Rudi is pretty much out of the game these days - but my info. is not authoritative there.

 

 

[Downunder]

$12k for a crankcase? Is it a hand-forged unit for a Merlin? Sand castings run about $11/kg, so the basic casting cost would be about $100; amortising the dies would be about 50 cents; machining would be a few hundred; the rest must be gouging.

A person on another forum was asking about the jackets he saw Rotax reps wearing and if he could get one.

 

Someone replied sarcastically it would be $50 dollars for the jacket and $300 for the embroidered name!!!

 

 

[Russ]

It,s a pity "known problems" are not warranty protected even when your wty time has expired, or even at min, a 50.....50 cost share, maybe.

 

Being left out in the cold is a hard pill to swallow, yr or 2 back our LG fridge/freezer was not happy, out of wty as well, a courtious call to customer relations, and they picked up the bill to my surprise........love LG products.

 

 

[Bob Llewellyn]

It,s a pity "known problems" are not warranty protected even when your wty time has expired, or even at min, a 50.....50 cost share, maybe.Being left out in the cold is a hard pill to swallow, yr or 2 back our LG fridge/freezer was not happy, out of wty as well, a courtious call to customer relations, and they picked up the bill to my surprise........love LG products.

"Zis problem is honly a problem if ZE ENGINES ARE OPERATED INCORRECTLY!! (!!!) Zere is NO FAULT VITH ROTAX, BECAUSE ZEY ARE ROTAX!!!!!!!!!!!!!!!!!!!!!!!!!!"

Nothing to do with effective monopolies and fear of litigation of course...