PAW vibration problem
#1
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A very good friend of mine picked up a PAW I think a 29.Bad vibration problem
I think caused by that(( iron piston weight of)) Engine is very out of Balance
My thought unbalance a prop and see what position on the crank this will cancel
some of this out any thoughts on this my paw 19 and 40 do not suffer this problem
His may be a very old one but runs ok except for the vibration problem very apparent
on test stand will shake a plane apart.
I think caused by that(( iron piston weight of)) Engine is very out of Balance
My thought unbalance a prop and see what position on the crank this will cancel
some of this out any thoughts on this my paw 19 and 40 do not suffer this problem
His may be a very old one but runs ok except for the vibration problem very apparent
on test stand will shake a plane apart.
#2
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Martin,
I have a PAW diesel sitting somewhere. It is a 1.5cc counter-piston type.
This engine has no crankshaft counter-weight at all, just a full circle, constant thickness crank-web, with a crank-pin sticking out.
Maybe on a control-line plane it will not matter, but in an R/C plane, it can cause your radio to "glitch".
Yes it has the heavy meehanite piston.
I have a PAW diesel sitting somewhere. It is a 1.5cc counter-piston type.
This engine has no crankshaft counter-weight at all, just a full circle, constant thickness crank-web, with a crank-pin sticking out.
Maybe on a control-line plane it will not matter, but in an R/C plane, it can cause your radio to "glitch".
Yes it has the heavy meehanite piston.
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The PAW 29 and 35 are not counterbalanced as well as the .40. I suspect with smaller motors the vibration is not such as issue. I know that Joe Wagner advocates the unbalanced prop idea--putting the heavy blade opposite the piston when the piston is at TDC. Haven't tried it myself. I have the .033, .06 and .40 and they are quite acceptable. Jim
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I have a number of PAW's and do not have any vibration problem. Is it a new engine? By the way, Dan, your run-on sentences and punctuation are atrocious! You sound like an Indian refugee. This is not like you! Stayin' up too late?
Max
Max
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Slow day and reading old posts. I have owned 4 PAW .15 Texaco engines, one .15 Special, a .40 and a .60. Only one had a vibration problem. It was a .15 Texaco and the second I purchased. My first PAW .15 Texaco flew away in 1995 and a purchased two more. Running these two engines in on the test stand one had a bad vibration with the 9/5 run in prop. The vibration disappeared with an 11 and 12 inch props. I also ran in in a PAW .15 Texaco for a friend and it had no vibration problem. Both the .40 and .60 purchased after the .15 engines were smooth running with run in props and larger props. I use the one that vibrates with the 9/5 prop to test home brew fuels and such. Jack