I wouldn't. That's the other reason to index the prop correctly. 2 and 8 viewed from the cockpit is about 10 and 4 viewed from the front and is correct for propping.
Kevin1 --- In [email protected], "Andy Anderson" <an...@...> wrote: > > How would you like to hand prop one that stops in the 2 & 8 position. It > is scary enough hand proping from the 10 o'clock position. You young bucks > probably never were trained on hand proping. We had no other choice on > light aircraft "back in the day". And I really did walk 5 miles to school > up hill, but only in one direction. > > Andy > > > > David, > > > > 11 and 5 viewed from the cockpit is not correct and will cause vibration. > > Viewed from the cockpit is should be more like 2 and 8. > > > > Kevin1 > > > > > > > > --- In [email protected], "drdlhammond" <drdlhammond@> > > wrote: > >> > >> Hi Kevin, > >> > >> We had the prop off during the March 2010 annual and it was re-mounted > >> in the same spot on the hub. Engine vibration following the annual was > >> no different than prior to the annual. The increase vibration was noted > >> following replacement of the rubber motor mounts. > >> > >> After re-indexing the magnetos during the annual (to obtain proper > >> impulse coupling for hand propping the engine), the prop stops at the 11 > >> and 5 position as viewed from the cockpit. Again, the engine vibration > >> post-annual was not different that pre-annual. > >> > >> Thanks, > >> David > >> N95CV > >> > >> --- In [email protected], "Kevin" <kgassert@> wrote: > >> > > >> > And make sure the prop is mounted in the proper spot on the hub. When > >> your engine stops does it usually stop with the blades at about 10 and > >> 4 looking at the front of the aircraft from outside? > >> > > >> > Kevin1 > >> > > >> > > >> > > >> > --- In [email protected], "BobD KSVE" <bevbobdtn@> wrote: > >> > > > >> > > David, > >> > > When I bought my coupe N3047H, it had a bad vibration. After doing > >> what you are doing, motor mounts, clearances, engine stuff, dynamic > >> balancing, we removed the prop and took it to a prop shop. They > >> promptly red tagged it!! (someone had drilled a couple of extra > >> holes in the back of the hub) > >> > > > >> > > A new prop and dynamic balance and empty wallet later and I could > >> finally make out the writing on the gauge faces while flying. > >> > > Bob D. > >> > > 1946 415E N3047 "Honey" > >> > > Susanville, CA > >> > > > >> > > > >> > > --- In [email protected], "drdlhammond" <drdlhammond@> > >> wrote: > >> > > > > >> > > > Hi John, > >> > > > > >> > > > How can I/we tell if the rubber motor mounts are bad??? The AP > >> thought they looked normal (i.e. compared to others he had > >> replaced). His torque wrench was "validated" about 1-2 months > >> prior to my job (he questioned both the 60 inch pounds - too tight > >> - and his wrench but a second, older wrench was almost identical). > >> Should we further tighten the mounting bolts? > >> > > > > >> > > > Both magnetos checked good during the March annual and both have > >> been acting "normally" since (i.e. no difference has been noted > >> during engine run up prior to take off). Yes, the right exhaust > >> pipe vibrates enough to touch the cowling at its exit hole (has > >> since I bought the plane a little over 2 years ago). Otherwise, > >> we have not found anything that touches the cowling. I will pass > >> along the suggestion to check for valve spring and lifter > >> malfunctions. > >> > > > > >> > > > The engine vibration reminds me of the old K&B 0.35 > >> nitro/methane/castor oil model airplane engines we used in the > >> late '60s and early '70s. These engines were mass produced and > >> inexpensive. Regardless of how well the prop was balanced, they > >> vibrated! At the time, older modelers told me these engines were > >> not internally "balanced" and thus their vibration. How much > >> engine vibration is "normal" for a 43 year old 4 cylinder 4 stroke > >> engine??? > >> > > > > >> > > > Thanks for your input! > >> > > > > >> > > > David > >> > > > N95CV > >> > > > > >> > > > --- In [email protected], John Cooper <john@> wrote: > >> > > > > > >> > > > > On 8/14/2010 10:32 AM, drdlhammond wrote: > >> > > > > > We could NOT tighten the mounting bolts to the prescribed 60 > >> inch > >> > > > > > pounds (we had metal to metal contact between the engine and > >> the > >> > > > > > mount). At 45 inch pounds there was very little clearance so > >> we > >> > > > > > settled on 40 inch pounds. > >> > > > > > >> > > > > OK, there's something wrong there. Bad rubbers, bad torque > >> wrench??? > >> > > > > > >> > > > > Once that's corrected, there are many possible causes of > >> vibration. > >> > > > > How's your mag check? Any baffles, exhaust or intake parts > >> touching the > >> > > > > cowl? Broken valve springs? Bad lifters?.... > >> > > > > > >> > > > > -- > >> > > > > John Cooper > >> > > > > Skyport East > >> > > > > www.skyportservices.net > >> > > > > > >> > > > > >> > > > >> > > >> > > > > > > > > > > ------------------------------------ > > > > Yahoo! Groups Links > > > > > > > > >
