[rebel-builders] Dyanfocal engine mount "vent" hol

[Wayne G. O'Shea]

I'd use them to your advantage Dave.. spray some tube seal in there to stop
any rust action and a dab of sealer to close them off. Can't weld them now
that you're powder coated.

----- Original Message -----
From: "David A. Ricker" <daricker@ns.sympatico.ca>
To: <rebel-builders@dcsol.com>
Sent: Saturday, December 18, 2010 5:09 PM
Subject: Re: [rebel-builders] Conical engine mount


[quote]Hi Simon

That's about what I figured and I'm surprised that they were left open.
Perhaps that's a comment on process control?

From your experience is closing them a "must do"?

Cheers,

Dave


On 12/18/2010 11:20 AM, Simon Smith wrote:
[quote]Those are vent holes for the weld process and we usually close them after
the mount is completely welded. Dick none of the 4 cyl. Lyc's have
detachable mounts. I hope this helps.
Si
Rebel N431SS& N572TA
----- Original Message -----
From: "David A. Ricker"<daricker@ns.sympatico.ca>
To:<rebel-builders@dcsol.com>
Sent: Saturday, December 18, 2010 8:22 AM
Subject: Re: [rebel-builders] Conical engine mount



[quote]Dick

I'm a bit confused by your description of the 4 cyl mount. I have just
received a mount (and a cowling, maybe more about that later) from MAM
for the Elite project, on the invoice it's listed as a Dynafocal mount
not Conical as I read your message to say. Am I understanding your what
your wrote correctly?

Now, a question of my own, the mount we just received has a small (about
1/16 - 1/8" dia) hole/gap in the weld between the support tubing and the
ring which accepts the lord mount. The hole looks to be intentional as
it is there on all 4 rings, any thoughts as to the reason? FWIW, The
mount is powder coated.

Cheers,

Dave

PS. After ordering a cowling, engine mount and window rings in January
2010, they arrived this week.



On 12/17/2010 10:42 PM, Dick Wampach wrote:

[quote]Marc you say Lycoming B2C for your Rebel I assume a 4 cyl.

About 5 years ago I contacted Murphy. Nancy sent me photos of the only
two
mounts that they market.
Most if not all of the smaller (4) cyl engines have the four mount lugs
cast
into the case of the engine (non removable). As I understand "Conical
engine
mount"
Most of the bigger engines(6) cyl have four bolt on lugs attached to
the
engine case with 4 studs. Commonly called "Dynafocal" mount's
There are 2 types of lugs out their:
Cessna uses the one with a 18* merging angle. That is to say
they all point to the front of the engine at approximately the prop
flange.
Piper uses a 30* lug which merges at about the center of the
crankshaft.

I hope this clears things up or all of you builders!

OK; so Murphy uses the 30* Dynafocal Motor mount configuration. One is
referred to as a "A", the other is a "B" configuration. The Lord
rubber
mounts are not interchangeable.
The P.N. for use with Murphy 30* system Mounts J-3804-20 from PA-23-250
PA-24's PA-25's, and a few others.


SO if your problem is that you can not use the Murphy engine mount with
your
O-540 all you have to do is buy new mount lugs from Lycoming for a few
thousand $$ (an expensive option).
Or modify the mount to fit your 18* engine (not a good option).
Third and best choice was to use the lead that Nancy Puff gave me.
For the cost of freight only, Aero Sport Power in Canada, about 50
miles
away from the Murphy factory. They had a need for the used but not
abused
18* mount lugs and were willing to exchange certified 30* parts with
me,
great people to deal with.

Dick Wampach SR-108 N331RW



-----Original Message-----
From: mike.davis@dcsol.com [mailto:mike.davis@dcsol.com]
Sent: Friday, December 17, 2010 3:05 PM
To: rebel-builders@dcsol.com; rebel-builders@dcsol.com
Subject: [rebel-builders] Conical engine mount


-------- Forwarded Message ---------
Original: DATE..... 12/17/2010 6:52 AM
Original: FROM..... Marc van Hulzen