6 cylinder surprise

[Blueadventures]

Definitely a good development; however will add a little weight which may be offset by the shorter less mass of the prop flange / spacer.

[johnm]

and this ............... I assume

 

 

[onetrack]

It's incredible what the machining abilities are, of the new types of cutting tips. Physical Vapor Deposition (PVD) and Chemical Vapor Deposition (CVD) coatings have revolutionised machining with their ability to cut like diamond-tipped tools without the level of breakage that DTT's suffer from. Cylindrical grinders have become obsolete today, as you can now acquire tips that will machine chrome like butter.

[facthunter]

Why would a billet Crank weigh More than a forged one? I can't see why it would have to. (refering back a little way). Nev

Edited April 30 by facthunter

[Blueadventures]

24 minutes ago, facthunter said:

Why would a billet Crank weigh More than a forged one? I can't see why it would have to. (refering back a little way). Nev

If question is about my posts reference to weight it was referring to the additional material at the forward end on the case (crankcase) that would allow for more distance between the two bearing there to add better support and that would mean the prop adaptor flange and its spacing to be shortened as explained by Paul.  I reckon you would enjoy a day or two in Pauls workshop; I know I would.  Cheers.

[facthunter]

Thanks. Often cranks have sections that are much weaker than the general section and that concentrates stress in those  areas. Poor design. Usually where a throw goes to a crank pin section. Billet is not really like a bit of grained timber as some imagine if it's rolled properly.  The ends of each rolled length should be discarded if there's any chance of a Scarf being there..  Nev

[BrendAn]

1 hour ago, Blueadventures said:

If question is about my posts reference to weight it was referring to the additional material at the forward end on the case (crankcase) that would allow for more distance between the two bearing there to add better support and that would mean the prop adaptor flange and its spacing to be shortened as explained by Paul.  I reckon you would enjoy a day or two in Pauls workshop; I know I would.  Cheers.

I have been there. Great bloke's . They do some brilliant work. The radial engines are a work of art.

[BrendAn]

On 27/04/2025 at 7:20 PM, GolfWhiskeyHotel said:

I follow this forum at irregular intervals , but given the latest news re: Jabiru Gen 4 , I thought "I wonder what everybody is saying".  So I came for a look.  Now I know what everyone is saying . NOTHING.  Not one post?  But People are being told

"Your engine will require a new crankshaft" , please join the queue.  Has no-one anything to say?   I hear that 3 or 4 hundred engines are involved. Worldwide.  Seems to me to be a postworthy subject wouldn't you think?

My aircraft is not involved of course, being a J160 with 912uls engine. (coming up to its third year and MARAP yet to be completed) . Happy Hours in the sky................ Geoff

 

Edited May 2 by BrendAn

[facthunter]

Recalls and extending warrantees are a good thing. Nev

[madhatter]

I recently purchased a gen 4 3300 however it now requires a new crankshaft. The engine only has 37 hours total time. I requested an exchange engine but was turned down so it will be torn down to correct the issue, very disappointed in Jabiru over this. I will incur a lot of expense and down time because of this, if this was Lycoming, Continental,  or Rotax it would be exchanged. I can install it myself, I've been maintaining aircraft for 52 years. Even with this I am impressed with the 230D aircraft. 

On another subject: I believe the new E-PROPS propeller being developed would be a game changer on a Jabiru. I was able to perform an analysis on Flight Design with an E-PROPS propeller which resulted in it being approved for all FD aircraft in the US. The performance increase is substantial for cruise speed, rate of climb, vibration, etc. The other important aspect is it has a very low moment of inertia which is less than half of that on the fiberglass prop for the 230D. This significantly reduces the gyroscopic forces on the crankshaft. The E-PROPS propeller and spinner only weighs about 5 lbs.

If Jabiru doesn’t approve the use of it within a reasonable time I will convert to experimental and document the analysis like I did with Flight Design. 

[facthunter]

The DEAL in Australia seems a much better one, regarding the Crankshafts.  Nev

[BrendAn]

18 minutes ago, facthunter said:

The DEAL in Australia seems a much better one, regarding the Crankshafts.  Nev

Why. Jabiru are only supplying cranks. Nothing else.

[facthunter]

That's not how I read it.  The warrantees are extended for the Listed Engines.  Nev