Too much compression

[jwp]

I have a 55 rancher that is always giving me fits to crank because it has too much compression for me to easily pull the saw to start it. I got it out a few days ago and tried to pull it and just could not get it to turn over fast enough to crank. Finally I took out the 024 av and cranked it to cut up some fire wood.

Would you guys put in a compression release or just trade saws letting the husky go to someone that has a stronger arm?

 

[blsnelling]

The 55 is not a high compression saw. Is your starter rope as long as possible? That makes a real big difference.

 

[TK]

Common complaint on 55's. Even though the comp #'s aren't high, they can be a bear. I believe it has to do with a smaller recoil pulley diameter where the rope coils around amongst other things. Smaller dogs on the pulley also putting pressure closer to the middle of the flywheel. The torque required in the design makes it seem like higher compression.

 

[jwp]

You may have a typo. If you meant to say starter rope, then the rope is long enough. I can start the saw fairly easily after it is warmed up or if the weather is hot. But when the weather is cold the oil in the saw is stiff and the compression is more than I can handle. I have never put a compression tester in the plug hole to see how much compression is there.

If there is a spark plug extension that would drop the compression, then that might be good enough to drop the compression.

If anyone has any ideas how to drop the compression using something simple, then let me know.

 

[jwp]

I can easily believe that the saw is not a high compression saw. I makes perfect sense that the starter pulley is too small making the saw seem to have high compression.

 

[half_full]

I just sold a 55 that was like that. Pull the rope slowly to get it just past where you feel the high compression. Then let it rip.

 

[jwp]

I will give that technique a try.

 

[BigDee]

I had an older saw that got harder to pull over. Finally I pulled the jug and found it heavily carbonned. I guess I had set it up too rich. After I scraped it clean, it was much easier. And lower compression too I guess. It did not seem to run differently than before.

 

[redunshee]

Picked up a 266xp that was hard to pull. I had to put my foot in the foot pad to start it. Friend of mine doing some logging with a 372 tried to drop start the 266 and almost dropped the saw. No way can you drop start it.

 

[old guy]

I have a poulan wildthing I bought to lend out that is like that, it will start on 4 pulls if you can pull it over.
Have no problem with 2 other larger poulans.

John

 

[mountainlake]

A rancher 55 has decent compression, mine is 155# and it's not perfect.. As Brad said make sure the rope is a long as possible without bottoming out the spring. More rope gives it more torque to get it spinning. Steve

 

[CR888]

+1 on what Brad said. The longer rope can make a big difference...it sorta changes the gearing. Maybe he could chime back in and explain 'why' a longer rope makes it easier. A smaller rope means if you say pull the cord a foot the crank will turn more than if the rope was longer (wrapped around starter), a one foot pull would turn the crank less thus making it easier. I'm terrible at explaining things but u may get my drift.

 

[cutforfun]

Picked up a 266xp that was hard to pull. I had to put my foot in the foot pad to start it. Friend of mine doing some logging with a 372 tried to drop start the 266 and almost dropped the saw. No way can you drop start it.

I have yet to find a saw that i could not drop start, i find with high compression and larger saws they start better that way.

 

[mountainlake]

To put it simple, the farther out you get from the center of the crankshaft the easier it will be to turn over. More rope is farther out. Steve

 

[mtlogdog]

my vote is you have oil and crud in the starter coil ive had the exact problem before i srayed brake cleaner with it off the saw and pulled it over while doing it. done this a couple times you might have to spry some wd40 of a silicone lubricant that does not atract dirt just a thought

 

[066blaster]

On other small engines that I own the shorter the rope the easier the pull. I got 18 horse v twins I can start with 2 fingers . Only has a foot of rope. I would think a chainsaw would be the same. Pull some rope through your starter handle and tie a knot to make it shorter and give it a try. Someone correct me if I'm wrong . But only if you know your right . They do start harder in the cold . Bring it inside for a while.

 

[066blaster]

It's like on a bicycle it's easier to pedal with the chain on the small sprockets . It's easier to pull with less rope coiled up in there.

 

[066blaster]

+1 on what Brad said. The longer rope can make a big difference...it sorta changes the gearing. Maybe he could chime back in and explain 'why' a longer rope makes it easier. A smaller rope means if you say pull the cord a foot the crank will turn more than if the rope was longer (wrapped around starter), a one foot pull would turn the crank less thus making it easier. I'm terrible at explaining things but u may get my drift.

Sorry but your wrong. Let's put it this way ,the more rope coiled up on the starter for each revolution of the starter you may turn the crank shaft 4 times ,less rope you may turn it 2 or 3 per starter revolution a 1:4 ratio is harder to pull than a 1:2. ever wonder why the starter gear on your car or truck is so small?

 

[dl5205]

It's like on a bicycle it's easier to pedal with the chain on the small sprockets . It's easier to pull with less rope coiled up in there.

Blaster, in this case the starter pulley is acting like the cogs on the rear wheel of the bicycle, not the chainrings on the front. Bigger diameter gives you a longer lever (radius) to turn the crank with.

On your automotive starter analogy, the saw starter pulley would compare to the flywheel gear, not the gear on the starter drive.

 

[066blaster]

Blaster, in this case the starter pulley is acting like the cogs on the rear wheel of the bicycle, not the chainrings on the front. Bigger diameter gives you a longer lever (radius) to turn the crank with.

On your automotive starter analogy, the saw starter pulley would compare to the flywheel gear, not the gear on the starter drive.

Yes but we are taking about the rope coiled up on the pulley not the pulley itself . It changes the ratio and creates more work if it's longer. Did you ever notice the first foot is the hardest, cut off a foot and eliminate it. Like I say I have 3 big 4 stroke engines with short ropes because they broke they pull way easier now. So I will hold my position on this.