Recent Acquisition

[Wiplash]

Over the holiday weekend I stumbled upon what I hope turns out to be a good find.

So this fella recently moved to my area from California with 2 aged airframes along with an aging kit. Several bags full of gauges, bolts and fuel system parts. There are axles and a tote of loose parts with a Mac case, two Holley carbs and more odds and ends. One airframe has a complete Mac engine that turns and has compression, I'm sure will need rebuilt though.

It's all in my garage now... Hope to have enough to get at least one airworthy gyro out of it all.

[scottessex]

Looks like some real pieces of history! :)

[dragonflyerthom]

Nice find.

Hope you get them airborne or at least one.

[Wiplash]

Is there a visual que to determine if this engine is a 72hp or a 90hp Mac?

[Passin' Thru]

Is there a visual que to determine if this engine is a 72hp or a 90hp Mac?

Yes. Look in the exaust stack; one divider rib in the center, it a 90. two divider ribs equaly spaced, it's a 72. ;)

[Wiplash]

Much obliged :yo:

I'll give it look in the morning...

[Wiplash]

Looked into the exhaust ports and they have 3 ribs... :eek:

Hope that's not a bad sign, I know there are certain engine components that shouldn't be used. I don't have the manual with me but I should be able to view it this weekend.

Been tinkering with the airframes. before they get torn down for rebuilding. One of then gyros has a head that I've not seen before.

Anyone familiar with this design?

[Timchick]

It looks like someone tried to build a head with some rotor head parts. I know I would not use that design.

[Wiplash]

Thanks, I definately won't use it. It's an interesting idea. The only part that spins is the spindle on top which has two bearings. At least one problem it has is there doesn't seem to be a place for the rotor to teeter. Although the teeter could be built into the hub bar. There seems to be alot of travel in the cyclic and the head seems to have a large range of movement. About 1/3 more than the other gyro which looks to be a standard Bensen from nose to tail.

[Timchick]

The other gyro in the first photo at the beginning of the thread looks like a normal Bensen rotor head. I don't know what that other one is.

[Wiplash]

Stood them up on the axles for tinkering before they get stripped down. They both have a 2x2 mast but included in the package is enough 1x2 and 2x2 for a 3rd airframe. I'm assuming from a KB kit.

The Stop sign tail is toast, about all it could be used for is a template. I'm thinking of using the aluminum tail. Any reason I shouldn't use it? There are some rusted pop rivets that I'll replace.

I'm confident the "Bensen" has flown. I am equally confident that the other one has not. They both look like they had been forgotten about in a barn for years without being properly pickled.

[scandtours]

Cylinder exhaust ports (if not exhaust muffler is used) should be turned 180 degrees.
Use cooling cowls

[Wiplash]

Thanks for tip.

It did come with cooling cowls but no exhaust.

Being a 2 stroke it suprises me that people run these without an exhaust. I don't intend on running it without one.

Here's what appears to be a complete kit. Threw the Bensen hub bar in there show. The news paper that some of these parts were rapped in had advertisements for "Star Wars", "Porkies" and "Best Little Whorehouse in Texas"...

.

[Wiplash]

Anyone have a drawing or picture of the porp hub puller? Or a good description of one?


Thanks,
Todd

[Timchick]

The way the piston wrist pins are in is determined by the way the cylinders are mounted (exhaust ports up or down). If you plan on running that engine make sure the wrist pins are in correctly.

[Wiplash]

Thanks Tim!

Duly noted.


Anyone have a drawing or picture of the porp hub puller? Or a good description of one?

Todd

Umm, that would be a prop hub puller...

[scandtours]

The way the piston wrist pins are in is determined by the way the cylinders are mounted (exhaust ports up or down). If you plan on running that engine make sure the wrist pins are in correctly.

Good you mention it, Tim

[dabkb2]

I have a hub puller, I'll get a pic tomorrow

[scandtours]

Anyone have a drawing or picture of the porp hub puller? Or a good description of one?
Thanks,
Todd

Actually it's a must tool for all McCulloch owners.

[Wiplash]

Thanks.

Hmm, I bet I have a drawing of that in my KB plans... Hope so, there's a little more to it than I imagined.