028 clutch/drum interference

[JonCraig]

Bought an 028Super parts saw & pieced together what it was missing. New bearings, seals, clutch drum, oil pump gears. Clutch was on saw.

I put it all together painlessly. Trying to tune it, I can’t get idle low enough to keep chain from spinning. Not my first rodeo. I’m no expert, but I’m very confident in what L, H, & LA do.

If I turn the idle low enough that I can hold the sprocket still with my hand, the rpm sounds very low compared to my other saws, and saw dies within ~20 seconds.

It almost feels like the clutch drum (new, Oregon) is too tight to the clutch. I have tried with two 028 clutches. 1 came off a working saw, so I don’t suspect the springs. Results are the same.

Am I missing something dumb? We’re there variants in 028 clutches and/or drums?

Tried to take a picture best I could to show the clutch shoes to drum clearance. Note that where it touches is because I don’t have anything to hold the two perfectly centered.

Another thing crossed my mind, and I don’t like the thought of it... Would a bent/warped crank cause this? Seems like maybe not, since the drum is also referenced to the crank, the two should move together...

Thoughts?

 

[mathewsdxt75]

If you can't hear the drum dragging while not running, I would suspect weak clutch springs. Is the drum bearing lubed and not dry and sticky?

 

[JonCraig]

Clutch bearing feels good. Tried oil first, then tried grease. No difference.

 

[mathewsdxt75]

Wouldn't hurt to measure the crank where the bearing rides compared to where it don't to see if it is worn.
When the clutch is tightened up ,does the drum feel free?

 

[JonCraig]

Just ran it w/out clutch (didn’t over-rev) and crank doesn’t wobble. Think I’m good there.

With everything installed, it feels totally normal. No excessive slop in drum bearing, and with saw off, spins totally free and spins for a good few seconds before gradually slowing.

It’s gotta be either the drum too small or the springs, right? Couldn’t be much else?

 

[HarleyT]

I don't see any pics.

 

[HarleyT]

Put on the old sprocket and compare.

 

[mathewsdxt75]

I'm assuming the parts saw didn't come with the old drum.
I just replaced the drum on my 028wb. I'll go measure them.

 

[JonCraig]

I'm assuming the parts saw didn't come with the old drum.
I just replaced the drum on my 028wb. I'll go measure them.

Correct—just the clutch, which was a bear to get off.

That would be great if you could measure, thank you!

 

[pioneerguy600]

I believe your clutch is off an 032.

Nix that, the 032 and the 028 both use 1113 clutch shoes.

 

[J.W Younger]

Bought an 028Super parts saw & pieced together what it was missing. New bearings, seals, clutch drum, oil pump gears. Clutch was on saw.

I put it all together painlessly. Trying to tune it, I can’t get idle low enough to keep chain from spinning. Not my first rodeo. I’m no expert, but I’m very confident in what L, H, & LA do.

If I turn the idle low enough that I can hold the sprocket still with my hand, the rpm sounds very low compared to my other saws, and saw dies within ~20 seconds.

It almost feels like the clutch drum (new, Oregon) is too tight to the clutch. I have tried with two 028 clutches. 1 came off a working saw, so I don’t suspect the springs. Results are the same.

Am I missing something dumb? We’re there variants in 028 clutches and/or drums?

Tried to take a picture best I could to show the clutch shoes to drum clearance. Note that where it touches is because I don’t have anything to hold the two perfectly centered.

Another thing crossed my mind, and I don’t like the thought of it... Would a bent/warped crank cause this? Seems like maybe not, since the drum is also referenced to the crank, the two should move together...

Thoughts?

View attachment 633543 View attachment 633545 View attachment 633546 View attachment 633547

!st pic 8 o'clock position, is that spring ok?

 

[mathewsdxt75]

My clutch is 2.630. Drum is 2.701.
My drum is a different oregon part number . My drum is for 3/8.
My clutch has the same shoes as yours.

 

[pioneerguy600]

Oregon # 30384 is the correct drum for a 028, set comes in .325 from Oregon.

 

[JonCraig]

My clutch is 2.630. Drum is 2.701.

One clutch is 2.629. Second is 2.638. Drum is 2.709.

Sound to me like we have the same clearances.

I have 1 more 028. I think I’ll try swapping the clutch/drum tomorrow and see how it acts.

Thank you for taking the time to measure yours!

 

[mathewsdxt75]

That sure does seem like they are identical.
Not a problem.

 

[J.W Younger]

My 028 is like a poppin johnny, even with the idle at 2400 it will move the chain 2-4 inches on the hard pops.

 

[JonCraig]

My 028 is like a poppin johnny, even with the idle at 2400 it will move the chain 2-4 inches on the hard pops.

This intrigues me. Because after gasket delete, the squish on this one is right around 0.020, and sounds very “poppy”. I wonder if this is ultimately what I have going on?

 

[J.W Younger]

This intrigues me. Because after gasket delete, the squish on this one is right around 0.020, and sounds very “poppy”. I wonder if this is ultimately what I have going on?

When yon said the clutch spun for a while when you shut it off it has to be the shoes moving out.

 

[pioneerguy600]

Even if everything looks near perfect I would install new OEM clutch springs if you really want to try curing this chain creep. I have had good results doing so and made more than a few customers happy. Old used springs may look good but they have been stretched and contracted thousands of times by now in a saw this old.

 

[JonCraig]

Even if everything looks near perfect I would install new OEM clutch springs if you really want to try curing this chain creep. I have had good results doing so and made more than a few customers happy. Old used springs may look good but they have been stretched and contracted thousands of times by now in a saw this old.

Yeah. I’m going to run by the dealer today and get some. Can’t hurt, and it’s only $10...

Any tricks to installing the new ones? I seem to recall cussing a lot last time I installed springs in a clutch...