Revolution Pro Engine Mounting

[Rcmaster199 at aol.com]

Hi Dean, the Rev Pro's engine mounting is quite similar to what you  
described on Dr J. The early beams in the Rev Pro were fiberglass and  vibration would 
loosen the engine bolts all the time. The fix was to epoxy the  bolts in 
place which is what gary Kirby did on his.
 
The better fix was to use aluminum beams which is exactly what Andreas  Gietz 
went to on mine. Blue loctite secures them well.
 
As far as isolation, the rear of the beams are secured through a set of  
fairly large (about 1"od) grommets (like servo grommets just bigger). The  grommet 
is installed onto the firewall, and a through bolt secures the beam's  back 
end (from inside the fuse). The front of the beams are secured with lords.  
Early Rev Pro's used a 3/8" Lord mounts but my kit has 5/8". The rear end of the  
beams does not seem to be as affected as the Lord mounting you used on the Dr 
 J
 
Isolation with this rig is pretty good on the YS 140L that Gary is running.  
Gary and I added an extra ring at the nose, mounted vertically, and Gary has 
had  no problems. I haven't flown mine yet but it's getting close. Weba 160 on 
mine.  And BTW, the L isn't enough power for the present F3A schedules, but is 
fine for  the masters schedules.
 
Matt

The one  I had didnt used Lord mounts at the rear but had the firewall milled 
to accept  some very stiff rubber isolators that sandwiched on either side of 
the  firewall. It doesnt have a tie rod at the back. I didnt/dont run the  
mount, the beams with it were pretty iffy looking but mine was an early  kit.

Dean Pappas <d.pappas at kodeos.com> wrote:  
Does someone have a picture of the Rev  Pro setup?
Back around '91,  had a 9 lb-6  oz Dr Jekyll with a 120-AC, with the engine 
the motor mounted on  two 6" long rails. The front of each rail had a 5/8" lord 
mount to  the nose ring, and the back of each rail was tied to the firewall 
with the  same lord mounts. The rubber bits were aligned fore-and-aft. The  
mount had a horrible resonance at idle. I can still remember Dean Kraus  yelling 
"shut it down - shut it down" the first time I ran the engine  up. It shook 
that badly. The fix was to put a strap across the rear end  of both rails, and 
put a large screw in the middle of the strap that  stuck back through a rubber 
bushing in the firewall. This forced the  back of the mount to rotate, not 
wobble up and down or sideways. All of a  sudden, it was a really good mount. 
 
What is done in the Rev Pro mount to  keep the back end of the motor from 
wiggling up and down or  sideways?
 
Regards,
     Dean




Dean, the beams are quite similarto what you described in the Dr  J
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