J'Red CS2171 / Husky 372 Vibration at Idle

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Hard to make out everything one this little phone, You know what you see. I see it's a new catcher. Possible from a 2185? It dose seem to look wide? Eye it up when the bar is on.

Make sure the springs are twisted completely in place, 100%.
Then check the inside bolt of the spring to the head also. I would pull the 90°, green fitting and blow vent out with air and put a little silicon on the edge. (Dont get inside) They vibrate out and will also make the saw vibrate hard.

*Edit: 90° fitting rather.
what did I say
90 % fitting...lol
 
Woes it look like the flywheel has ever sheared the key. I talked to my buddy that works at a small engine shop by me. He said some saws have had someone hit the break at wfo. Says it sheared the key and ruined the crank (out of phase). Claimed to have seen it a few times. He said it was more common on saws that had a replaceable key. Said it was harder and didnt shear as easy and alowed more twisting shock to the crank stopping so abruptly. It makes sence in my head how that could twist the crank out some. Stopping fast and hard ar 14000 rpm gotta shock the heck outta stuff.
 
If you are worried about your crankshaft being tweaked out of phase and lack dial indicators and such to accurately check run out...try this redneck/field test......adjust your chain rather tight then remove the spark plug....now slowly pull the engine over and pay close attention to the chain.....does it remain adjusted tight like it was? Or does it get tighter or loser as you complete the revolution? If it stays the same likely your crank is not at fault.....if it changes back and forth you have problems...
 
Do you have hard or soft AV's? I also noticed you didn't have the sleeve over the adjustment screws. The limit caps removed also give you a smaller target to hit.
 
Do you have hard or soft AV's? I also noticed you didn't have the sleeve over the adjustment screws. The limit caps removed also give you a smaller target to hit.

Yep all those things can certainly add to frustration when trying get your screwdriver on the adjustments.....another thing that may help is to turn the idle up to 2500-2600 or so just below the chain engagement....this will smooth the vibration out a bit...won't be hopping all about at a slow idle....
 
Yep all those things can certainly add to frustration when trying get your screwdriver on the adjustments.....another thing that may help is to turn the idle up to 2500-2600 or so just below the chain engagement....this will smooth the vibration out a bit...won't be hopping all about at a slow idle....

Not sure I've found a direct culprit yet. I'm fixing what I see one-by-one and will reassemble the saw when I've replaced the crank seals. Basically, I'm not feeling a vibration when I'm operating the saw, it occurs more when I sit it on the ground and try to tune it. I've tried it with a high idle and ran the L screw back and forth from lean to rich and the vibration remains. At first, what it reminded me of was the carb not being properly secured. As if one of those little mounts on the bottom of the intake had gotten broken. Since I'm this far into it, I'm debating whether to just go ahead and split the case, check the crank and replace everything and start from basically new.
 
Do you have hard or soft AV's? I also noticed you didn't have the sleeve over the adjustment screws. The limit caps removed also give you a smaller target to hit.

There are two different AV springs for these saws .........Standard ones with part # 503 63 76-01 for the front and # 503 89 56-01 for the rear spring. There are also Hard AV springs are part # 503 63 76-02 for the front and part # 503 89 56-02 for the rear. It would stand to reason that you would certainly encounter more vibration at idle if it was fitted with the hard springs rather than the standards. You might want to look into this before splitting the cases......

Interestingly, the difference in price between the std and hard springs is around $8.00 on the front mounts and only about a buck difference for the rear...
 
Not sure I've found a direct culprit yet. I'm fixing what I see one-by-one and will reassemble the saw when I've replaced the crank seals. Basically, I'm not feeling a vibration when I'm operating the saw, it occurs more when I sit it on the ground and try to tune it. I've tried it with a high idle and ran the L screw back and forth from lean to rich and the vibration remains. At first, what it reminded me of was the carb not being properly secured. As if one of those little mounts on the bottom of the intake had gotten broken. Since I'm this far into it, I'm debating whether to just go ahead and split the case, check the crank and replace everything and start from basically new.
My 372's will dance around on hard ground, no way can I keep a screwdriver in a needle slot, doubt you have a problem. Tune them holding saws or resting bar on a piece of wood. Thought you where talking about vibration running and cutting with saw.
 
I agree,some saws will vibrate considerably if sitting on a hard surface. Also I would want to check the crank with a dial indicator. A twisted crank will cause excessive vibration in many other 2-strokes too,such as bikes and snowmobiles,not that uncommon...
 
I'm going to check it out. Putting a MMWS ported cylinder on this thing so I want to make sure it's 100% before I build it up.
 
Back
Top