---------------------------------------------------------- Tailwind-List Digest Archive --- Total Messages Posted Sat 08/23/03: 1 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:59 AM - Re: Dynafocal Rings (William Bernard) ________________________________ Message 1 _____________________________________ Time: 04:59:01 AM PST US From: "William Bernard" Subject: Re: Tailwind-List: Dynafocal Rings --> Tailwind-List message posted by: "William Bernard" Jim, the mounts I used are such that there is a "front" and "back". I presume that the rubber is stiffer for the part of the mount loaded in compression. This part goes on the front on the bottom side and on the back on the top side. In looking more carefully at the mount, the bottom mounts seem to be compressed pretty evenly, it is only the top two that are off. And they are not off by the same amount. At this point, I see two main possibilities: either the mount ring was made poorly, or it warped during welding. The tubing shows no distortion and it seems that if the mount would warp, it would be at the bottom since those cups are only attached by one side, not two. I'm still studying the thing and deciding what to do. The plan so far is to try to look at another cessna mount and see if it shows the same thing. I probably will leave it and run the engine for a while and see if there is a problem. I suppose it would be possible to cut out the top two rings and re-weld them in a better orientation. Bill ----- Original Message ----- From: "Jim and Donna Clement" <168x@merr.com> Subject: Re: Tailwind-List: Dynafocal Rings > --> Tailwind-List message posted by: "Jim and Donna Clement" <168x@merr.com> > > Some lord rubber mounts have a set position, like top left side and so on. > Different part numbers for each in a set. Were they used with the mount? Try > matching them up tops and bottoms. Twin Comanche is the only one that I know > of that uses the type 2. You must have the right one, the rubber mounts are > a mixed set. Jim > ----- Original Message ----- > From: "William Bernard" > To: > Subject: Re: Tailwind-List: Dynafocal Rings > > > > --> Tailwind-List message posted by: "William Bernard" > > > > > Jim, From what I can tell, the rubber mounts are down tight. The 7/16" > bolts > > can pull a lot! The bolts were not unduly difficult to insert, but it did > > require a bit of lifting of the engine to get the lower ones in. I found > > that I had to insert the top two bolts first and then the lower ones by > > raising the case slightly using a hydralic jack. The bolts then went in > with > > only light tapping with a plastic mallet. > > > > The bolts pulled up snug and all the mating surfaces appear to be in > contact > > their full diameter. I cannot see into the center of the mount ring, so > > there may be some misalignment there. The most visible 'defect' is the > > observation that the rubber mounts are not compressed evenly. > > > > I'm pretty sure that the mount was not off of a twin. I got the whole > mount > > (damaged, but the ring was intact) and so was able to determine that it > came > > off of a single engine of some type. > > > > Bill > > ----- Original Message ----- > > From: "Jim and Donna Clement" <168x@merr.com> > > To: > > Subject: Re: Tailwind-List: Dynafocal Rings > > > > > > > --> Tailwind-List message posted by: "Jim and Donna Clement" > > <168x@merr.com> > > > > > > Bill, I don't know for sure about the new Cessna's, but the old ones > > should > > > fit. Maybe they gave you a mount from a twin Comanche, they have a > > different > > > angle than the E2D. If it is the wrong one, I would think the bolts > would > > be > > > real difficult to get through the holes in the engine. Are you sure the > > > rubber mounts are seating evenly in the mount? Jim > > > > > > > > > ----- Original Message ----- > > > From: "William Bernard" > > > To: ; > > > Subject: Tailwind-List: Dynafocal Rings > > > > > > > > > > --> Tailwind-List message posted by: "William Bernard" > > > > > > > > > > > I've noticed something about the way my engine mounts and I wonder if > it > > > is anything to worry about or fix. > > > > > > > > The engine (O-320-E2A) is mounted on a dyafocal ring that is supposed > to > > > be off of a Cessna 172. I got the ring a couple of years ago from a > > salvage > > > yard. The engine went on with only the usual difficulties. The > observation > > > is that the rubber mounts are compressed unevenly - more on one side > that > > > the other for each mount. > > > > > > > > Comparing the ring on the Mustang II ( where the engine was previoulsy > > > mounted) shows that the angles of the mount pads are different, being > > > focused to a point further forward on the Cessna mount ring. > > > > > > > > I know there are Type I and Type II rings, and I've also read that > > Cessna > > > used a different ring on the mount for the new production 172s. > > > > > > > > Does anyone know how to tell the difference between the different > types > > of > > > mount rings? Is the asymetric compression of the mount rubbers anything > to > > > worry about, or do I need to be building a new engine mount? > > > > > > > > Thanks for the opinions. > > > > > > > > Bill > > > > N40WB > > > > > > > > > > > > > > > > > > > >