The Forestry Forum

General Forestry => Chainsaws => Topic started by: ely on April 20, 2009, 08:59:25 PM

Title: 4 stroke or diesel
Post by: ely on April 20, 2009, 08:59:25 PM
did we have a discussion here once about a 4 stroker or even a diesel chainsaw? did someone make these.?
Title: Re: 4 stroke or diesel
Post by: sawcollector on April 20, 2009, 09:19:04 PM
Comet diesel from Sweden was sold in the '50s. A fellow collector friend of mine has one. You filled the handlebars with propane to feed the open flame burner under the cylinder to warm up the jug before attempting to crank it. It is huge and heavy.
Dolmar showed a four-stroke at some shows a few years ago but never marketed it that I know of.
STIHL looked in to a four-stroke but did not develop it.
Title: Re: 4 stroke or diesel
Post by: ely on April 20, 2009, 09:23:14 PM
cool, am i correct in assuming this saw  had a crankcase with an oil sump.
if so i wonder how it does on its side felling trees. duoble pump pickups maybe?
Title: Re: 4 stroke or diesel
Post by: joe_indi on April 21, 2009, 01:05:28 AM
I wonder whether it is possible to make a diesel engine similar to those on aero models.
The compression ratio is decreased but this is compensated by the 'diesel' fuel ' having a lower flash point due to the blending in of ether.
I am not saying that ether should be used, but maybe a percentage of gasoline.

Title: Re: 4 stroke or diesel
Post by: Ironmower on April 21, 2009, 06:24:48 AM
Quote from: ely on April 20, 2009, 08:59:25 PM
did we have a discussion here once about a 4 stroker or even a diesel chainsaw? did someone make these.?
Yes we did. I asked a simular question not to long ago, 4-stroke & rotary saws. Don't know how to link ya, but I believe it's on page 3 ;) :)