crowe
ArboristSite Operative
How many of you guys have had a saw run backwards? I have an old 090 of my dads and every once in a while if I take it out to give it it's monthly start up it will run backwards. What causes that? Later, Wade
Saw running backwards
- Thread starter crowe
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Crofter
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Wade; just sharpen the backs of the cutters too and your good to go!
Frank
Frank
sedanman
Just cut the piano!!
A friend of mine had a Bultaco motorcycle that would do the same thing. Seems if the timing is set very close to tdc and the motor "kicks" instead of starting forward it will kick backwards and run. A two cycle engine does not care if runs forward or backward. You should have seen us try to ride the Bultaco backwards! Another friend of mine relied on the kick to get his r/c planes to start, he'd whack the prop in the wrong direction then feel the nosecone to see if the engine was running the right direction.
Fish
Tree Freak
I only see this on Russian/Polish chainsaws.
Dennis
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If I understand it correctly its a timing issue...usually correlated with high compression.....Not to bring snowmobiles into the conversation...but, some of the new sleds with reverse...actually kill the engine and start it backwards when you put it in reverse...( I know this will be corrected in a hurry if I am wrong....Ben??......lol) I have a Super 930 that I want to run backwards...but from what I also understand they never have the power that they do running the opposite(correct) direction.
logcutter429
ArboristSite Operative
I had a 2094 jonyred that would do it about once a week, odd aint it.
John in MA
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My Jonsey 111S came to me (and we think from the factory) missing one piston ring. I corrected that, then tried to start the saw. It sure wanted to run backwards! As soon as I flipped off the decomp it fired and broke the starter rope off. Found out that the timing was way, way off. Much better now.
I think it was Dave who had a poorly-timed 111 nearly take his hand off. Ouch.
I think it was Dave who had a poorly-timed 111 nearly take his hand off. Ouch.
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Bultaco motorcycles also if stalled on a hill could take off running backwards downhill. That would surely stain the undies!!!
running backwards
I was backing by boss's ( 671 detroit powered)dump truck up a slope when my foot slipped of the clutch....it died and started back up backwards blowing smoke out the air filter and sucking up the exhaust. the worst part is the oil pump is turning backwards as well "not pumping oil" probably not good in the long run but what the hell most detroit's don't have any oil pressure anyway.
jeff
I was backing by boss's ( 671 detroit powered)dump truck up a slope when my foot slipped of the clutch....it died and started back up backwards blowing smoke out the air filter and sucking up the exhaust. the worst part is the oil pump is turning backwards as well "not pumping oil" probably not good in the long run but what the hell most detroit's don't have any oil pressure anyway.
jeff
sawyer40
ArboristSite Member
This thread brings to mind a story dad always told about the fordson tractor he had hooked to a blower on the silo. When it was cold it would misfire and run backwards so any thing you put in the blower would come right back at you. then he knew enough to let it warm up shut it off crank and restart it forwards.
Tom Dunlap
Addicted to ArboristSite
My first Partner P100 would do that once in a while. Pretty weird.
Tom
Tom
paul soccodato
ArboristSite Member
alamo-kid,
i find it very hard to believe a 4 cycle engine ran backwards.
i find it very hard to believe a 4 cycle engine ran backwards.
Paul,
Detroit makes a 2-stroke diesel.
Detroit makes a 2-stroke diesel.
I read once that the early hand crank start automobile engines had a lever that controlled the spark timing. If you didn't set it in the right position to start it, the engine would fire backwards and try to take your arm off. That'd wake ya up real quick!
My2cents
ArboristSite Operative
Remember those tiny Cox model airplanes. They would start in reverse as often as foward. The directions read if this should occur just throw a rag at the propeller to stop the engine and try again!
running backwards
This thread also reminds me of a friend years ago that was building a modifyed pulling tractor. He located a surplus Allison aircraft engine in a salvage yard here in texas and installed it in the tractor . He and his partner pulled that thing "miles" behind a pick up trying to get it started with no luck, it would only backfire. After contacting the salvage yard the man said "what ever you do don't pull it backwards" It seems this was an engine off a twin engine plane with counter rotating props and they bought the engine that rotated the wrong way.
"ever tried to steer an Allison powered farm tractor wide open in reverse"
My boss "with the detroit dump truck" had two of these engines that came off Haliburton "frac trucks" he was also going to build one of these tractors but never got around to it. We drank a bunch of beer one saturday and tried to start one up on a stand. ???? thing hit once and almost turned over on us after that he traded both of them for a Cat powered dump truck....much safer on saturday afternoon.
jeff
This thread also reminds me of a friend years ago that was building a modifyed pulling tractor. He located a surplus Allison aircraft engine in a salvage yard here in texas and installed it in the tractor . He and his partner pulled that thing "miles" behind a pick up trying to get it started with no luck, it would only backfire. After contacting the salvage yard the man said "what ever you do don't pull it backwards" It seems this was an engine off a twin engine plane with counter rotating props and they bought the engine that rotated the wrong way.
"ever tried to steer an Allison powered farm tractor wide open in reverse"
My boss "with the detroit dump truck" had two of these engines that came off Haliburton "frac trucks" he was also going to build one of these tractors but never got around to it. We drank a bunch of beer one saturday and tried to start one up on a stand. ???? thing hit once and almost turned over on us after that he traded both of them for a Cat powered dump truck....much safer on saturday afternoon.
jeff
tony marks
Addicted to ArboristSite
guess i believe u boys. but its kinda like ufos . i ll believe it more when i run accross it.if i had one do that . it goes in the trade colum pdq.have enough problems keeping them running in the right direction.
daveb
ArboristSite Operative
Re: running backwards
I've seen detroits run backwards also, and you're right about the oil pressure, about 5psi at idle and 25 wot.
Gypo Logger
Timber Baron
My2cents post reminds me of when I was 15 and building model airplanes. I think it was a Pilatus Porter with a Cox .020 engine.
Anywho, it ran backwards and rocked out on my right wrist, requiring a few stitches. The funny this is, a Husky 266 chowed down on my left wrist ten years later. I once had a diesel airplane motor that was very tempermental at that time. It seemed to be a tourqey lil thing.
John
Anywho, it ran backwards and rocked out on my right wrist, requiring a few stitches. The funny this is, a Husky 266 chowed down on my left wrist ten years later. I once had a diesel airplane motor that was very tempermental at that time. It seemed to be a tourqey lil thing.
John
