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Conical bushings on dynafocal mount

RobinHou

Well Known Member
This is not a RV but a Pazmany, so I hope this post does not violate any posting rules. If it does, please remove it.

We are replacing sagging bushings in my friend's Pazmany PL-1B. The engine is a 150hp O-320 with Dynafocal mount, but we are not sure what type (I or II). However, the airframe engine mount has cups looking like engine block conical mount using bushings looking like Lycoming 71032.

71032 bushings have .5" hole but the mounting bolts are .402" like the ones used with Dynafocal engine mount with large cups. We are thinking using some type of metal sleeves over the bolts so the bushings do not deform too much under compression. I fount the following online from Great Plains website:

http://www.greatplainsas.com/i71032.html

However, Great Plains uses .5" OD with 3/8" ID metal tube as sleeves since it uses AN6 bolts (.371-.374"). Our bolts at .402" are not going to fit.

Is this a standard Lycoming installation? If so, is there a Lycoming kit (bushings, bolts, washers, sleeves, ...) to correctly mount this Dynafocal engine to its engine mount with conical cups? Part no. for the kit?

If not, any suggestion on how to correctly install these bushings is welcome.

https://picasaweb.google.com/112104387224491745925/N3237NPL1B#5719068234383154386

https://picasaweb.google.com/112104387224491745925/N3237NPL1B#5719068658826101362

https://picasaweb.google.com/112104387224491745925/N3237NPL1B#5719068869924640962

https://picasaweb.google.com/112104387224491745925/N3237NPL1B#5719069068741227522

https://picasaweb.google.com/112104387224491745925/N3237NPL1B#5719069253420287490

https://picasaweb.google.com/112104387224491745925/N3237NPL1B#5719069579336970610
 
Last edited:
No this is not a standard dynafocal Lycoming install but it is rather clever, since the conical bushings are far less expensive. They look like standard conical mount bushings to me.
 
The dimension 0.402" does not correspond to any standard dimension US or metric hardware. Not any I know of, anyway. I think that there is something strange going on here.

Thanks, Bob K.
 
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