Prop Unfeathering Accumulators - Question

[Frank Benvin]

Here is the page from my parts manual 1967 337b

[mshac]

Originally Posted by Frank Benvin

Here is the page from my parts manual 1967 337b

Thanks Frank. My manual is similar to yours.

I can see that the rear is mounted on the engine mount frame somewhere (with what appear to be hose clamps), but the front doesn't give much reference to where its installed.

Actual photos is what Id really love to see!

[mshac]

Actually, it looks it would require special governors as well as the accumulators, so I guess I'll just deal with the "shaky start up" upon unfeathering. Not willing to spend $3k on this little "improvement".

They were standard on O2s. If I were getting shot at, I'd want them for sure. The seconds they save on restart could save your life!

If I was gonna do ME flight training on a regular basis in it, I'd still consider them though.

[hharney]

Most of the accumulators on these planes were removed back in the day. No one wanted the maintain them and they just weren't needed. The start up isn't so bad without them and just go easy on the starter when you do this. Make sure you follow the procedure in the book for in flight restart, works like a charm

[Jhogan0101]

Here is one with accumulators trying to restart front engine.
@ 7:30

https://youtu.be/tAB486BKI10

[mshac]

Originally Posted by Jhogan0101

Here is one with accumulators trying to restart front engine.
@ 7:30

https://youtu.be/tAB486BKI10

You could see how hard it was on the starter, and they never even got it running again, at least in the video. Based on the narration, I assume they eventually did.

If the accum. was working, as soon as the prop lever was moved up out of the feather position, the oil pressure in the accum. would move the blades to their normal operating position, which would force the prop to start windmilling. Engine is spinning at this point, ready to start, without ever touching the starter. Just get the throttle/mixture setting correct, and it will fire right up!

I read you have to service the nitrogen in the accumulators every 90 days. Seems as if theirs had not been serviced recently. So glad I have my own nitrogen tank for servicing struts, would work for the accum. as well.

[Kim Geyer]

The rear accumulator was mounted on the RT side of the engine mount. the front was mounted in the nose wheel well forward of where the nose gear would be when retracted. The plane also had Woodard governors on it
Kim