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EAA Chapter 245 is rebuilding a Jabiru 3300 engine core as part of a chapter project. (We are building aZenith 750 Cruzer.)
We have found that the Jabiru engine backing plate is bent at two of the engine mount points - though it seems OK where it attaches to the case. Can we straighten the bent corners in a press? Should I contact the manufacturer for this question?
How much would a replacement plate cost? (PN 4A529A0D-4 I think ??).
Are there any used part sources out there? I would assume this back plate part might even be common across the engine models. I imagine there are a number of other parts we will need that could be from a doner engine.
I can't advise you on unbending the plate, however, my question would be WHY is the plate bent in the first place? Was this engine involved in some sort of incident/accident and subjected to high G-Loads or Impact? If so, was there a propeller strike that may have crankshaft ramifications? And so on . . . My inclination would be to reach out to Jabiru if any of the above conditions occurred.
The engine was in a plane where the engine quit due to fuel starvation just off the runway. It was a very hot day and we think he forgot to flip on his electric fuel pump.
The plane mushed into the top of scrub cedars. After the forward motion stopped it slipped nosed down between the trees to the ground. The impact broke one prop blade and bent the engine mount. The pilot walked away with a couple scratches and a bruised knee. (We did not notice the back plate until later.)
We cross our fingers and dialed the run-out on crank and it actually was even better than we hoped. The prop flange is just out of spec so we might end up replacing that.
Ditto Gary and Mike's comments, questions and suggestions!
Nick Otterback would likely the be the most knowledgeable person at Arion Aircraft, the US distributor/repair center for Jabiru. Mike gave you the contact link, but I've heard some comments that emails may not get a quick response and it might be best to just call during business hours and ask for Nick specifically. They can get you a new plate, but there might be a good chance they have a run-out engine they're parting-out and the plate off that would be much less expensive ... if (hopefully!!!) that's all you need. Nick/Arion would be an excellent shop to go-through your entire engine if indicated!
I've also had luck obtaining used parts from Skycraft in the UK. I don't see the plate listed online, but a query might be in order if you have no luck elsewhere.
Let us know how the rebuild goes ... I'd be very interested to learn if there was any further internal engine damage.
Hi John, I agree with what has been said by others but, it would be interesting to see if you can get the plate flat again. It would cost nothing to try and if you succeed and verify that it is flat in all aspects, check for cracks. The plate looks pretty bad though. My experience is that once something is bent, it is very difficult to undo all the compound bends that at first seemed easily fixable. If you don't have much invested in this engine I would shop for another engine and keep what you have that is good for spare parts or sell them.. Lastly, take the crank to a good engine shop and have it checked for cracks and run out. This is cheap insurance plus if you sell the parts you have paperwork from the shop.
I'll bet that even if it was successfully "flattened," it'll take some machining to get the resultant "waviness" out.
Agreed. Wonder how much it would cost to have a new T-6 plate made at a good machine shop, vs purchasing one from Jabiru?