'85 Whisper Chipper, new bearings and gapped but still not feeding well

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Hi All,
I've been going through the forums while rebuilding a recently purchased 12" drum Asplundh whisper chipper. I picked it up last year and it worked well, but often would have to throw the same branch in a few times to get it to disappear. I used it around the farm quite a bit but at one point I was just getting too frustrated having to keep putting the same branch in before it would chip part of it, then again...and again.
Based on the research here I figured it was the knives or the gap. One bearing was howling so I decided to replace both and start from scratch.
I got the new bearings in, and set the cutter bar 7/32" from the rotor. Then I installed the blades to be about .030 from the bar. After I torqued everything down I found the gap between the knife and bar was .026 so I moved the cutter bar down to get .028 which from other posts on here makes for an aggressive cut. I am the only one that uses this machine and its just for our property so if it doesnt get much use.
After all that work I fired it up in anticipation and it was disappointing to see some improvement but not much. The chips are about half the size of what they were before, the Ford 300 doesnt bog down at all as it ripped some 5" red oak, but it also only got through half of the 7' long bare branch.

What did I do wrong? I flipped the cutter bar to a new side, the blades all looked good and quite sharp (they were replaced a while before I bought the machine), a few little nicks but all and all a good edge.

I'd like to get it to the point where i can toss the branch in and it disappears while i go get the next one...chuck and duck. Any help would be much appreciated.

Thanks,
George

Hi All,
I've been going through the forums while rebuilding a recently purchased 12" drum Asplundh whisper chipper. I picked it up last year and it worked well, but often would have to throw the same branch in a few times to get it to disappear. I used it around the farm quite a bit but at one point I was just getting too frustrated having to keep putting the same branch in before it would chip part of it, then again...and again.
Based on the research here I figured it was the knives or the gap. One bearing was howling so I decided to replace both and start from scratch.
I got the new bearings in, and set the cutter bar 7/32" from the rotor. Then I installed the blades to be about .030 from the bar. After I torqued everything down I found the gap between the knife and bar was .026 so I moved the cutter bar down to get .028 which from other posts on here makes for an aggressive cut. I am the only one that uses this machine and its just for our property so if it doesnt get much use.
After all that work I fired it up in anticipation and it was disappointing to see some improvement but not much. The chips are about half the size of what they were before, the Ford 300 doesnt bog down at all as it ripped some 5" red oak, but it also only got through half of the 7' long bare branch.

What did I do wrong? I flipped the cutter bar to a new side, the blades all looked good and quite sharp (they were replaced a while before I bought the machine), a few little nicks but all and all a good edge.

I'd like to get it to the point where i can toss the branch in and it disappears while i go get the next one...chuck and duck. Any help would be much appreciated.

Thanks,
George
O
 
Could you help me with trying to replace the bearings on a 74 Whisper Chipper. I’m trying to restore one from the dead living in the elements for 18 years exposed. I’ve got the engine running but now the bearings are frozen shut.
 
Could you help me with trying to replace the bearings on a 74 Whisper Chipper. I’m trying to restore one from the dead living in the elements for 18 years exposed. I’ve got the engine running but now the bearings are frozen shut.
Hey, I still have mine, amazing machine, simple and damn near bulletproof. BUT: Violently dangerous, be careful, and then some.
That being said, the bearings are pretty simple but a royal pain in the butt. You’ll need a torch to heat it up, overhead crane or mounting point to raise the massive (500 pound? ) flywheel, but before all of that spend the first week just applying Kroil to the bolts and bearings.
I’m not sure if your machine is the same as mine but without welding up bracket to hold the flywheel there’s no way to disassemble and reassemble it.
 
She feeds and chips great but I still have to put an exhaust on her…..
 

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Thanks buddy, those pictures are a big help, mine is quite similar a 74 Whisper chipper.
I’m trying to bring mine back from the dead…sat out back for 18 years unprotected. Has a good engine and good clutch. Now I can’t remove the sheave from the belt side!
 
Thanks buddy, those pictures are a big help, mine is quite similar a 74 Whisper chipper.
I’m trying to bring mine back from the dead…sat out back for 18 years unprotected. Has a good engine and good clutch. Now I can’t remove the sheave from the belt side!
Kroil and patience. The pulleys and housings are all cast iron so they are quite brittle. Parts are hard to source so go slow. Clean everything up as best as you can, then heat it up and begin soaking it with kroil, and I mean Kroil, don’t cheap out on it, PB blaster is great, but it’s not Kroil. Couple times a day tap the surfaces and respray with Kroil. I’ve don’t this repair on two different machines now and you just have to go slow
 
Again thanks for the info! One more question if you will, how do I remove sheave after I have removed the three bolts…is it just stuck on from rust?
 
Again thanks for the info! One more question if you will, how do I remove sheave after I have removed the three bolts…is it just stuck on from rust?
"Three bolts" implies you have a QD or Taper Lock (or similar) bushed sheave. If so, there will be tapped holes (QD) or half tapped holes (Taper Lock) for forcing the sheave off the tapered OD of the bushing.

QD:
Taper Lock:
 
Hey Mike,
I got the knives sharpened (took about two weeks for them to finally get to them after I dropped them off). I set them in and did about a .030 thickness, maybe even a little less. And we are back in business - same as you said, anything longer than about 8' and 6" thick will bog it down. I'm using the chips around my house so I like the smaller size, but if I was using it to clear branches in bulk or professionally I would have set them to .032 to get larger, faster chips and being easier on the motor.
I actually bought the bearings off Amazon, they showed up and they were the right size, but missing the metal shield. I ended up sourcing the correct ones on eBay for $310 for the pair. Found new old stock belts for $60 for the 4 as well.
The bearings were SKF 6316 2RS1/C3 Deep Groove Ball Bearings the 2rs1 is the metal sheilds on both sides and the C3 is the grease they are packed with. There are other variations including one that has a wider heat range, but I wasnt about to spend $450 per bearing...
Not only does she chuck and duck now but she also whispers. I just have to figure out a new exhaust as the original one rusted out so its just a 4" header sticking out. Any suggestions on that?

A note on getting the fly wheel off....WOW. I used chains to secure a 30 ton bottle jack against the fly wheel to pump against the shaft. Heated the hell out of it then as it cooled it went POP. I also welded up a bracket to be able to move the massive weight away. If anyone wants to buy it let me know...will trade for an exhaust...
I’d be happy to buy that welded up jig you built from you. If you’re serious how can I reach you?
 
Hey, Nedsim is right it’s a taper, I believe there are three bolts but 6 holes, mine was really on there and the threaded three (unused) holes weren’t strong enough to break the rusted faces apart. Theory is you remove the three bolts, put them in the unused tapped holes, then slowly thread the bolts in and it will push the sheave off. Mine took lots of heat and kroil and time. It’s cast so you can’t really put
Too much pressure on it
 
Hey, Nedsim is right it’s a taper, I believe there are three bolts but 6 holes, mine was really on there and the threaded three (unused) holes weren’t strong enough to break the rusted faces apart. Theory is you remove the three bolts, put them in the unused tapped holes, then slowly thread the bolts in and it will push the sheave off. Mine took lots of heat and kroil and time. It’s cast so you can’t really put
Too much pressure on it
I did exactly that and yes I broke the sheave through, however now the sheave bushing is stuck. Also does that sheave bushing lined with a rubber ring around the shaft? Reason I asked I heated it and was wondering if I melted any rubber inner lining.
 
Hey Mike,
I got the knives sharpened (took about two weeks for them to finally get to them after I dropped them off). I set them in and did about a .030 thickness, maybe even a little less. And we are back in business - same as you said, anything longer than about 8' and 6" thick will bog it down. I'm using the chips around my house so I like the smaller size, but if I was using it to clear branches in bulk or professionally I would have set them to .032 to get larger, faster chips and being easier on the motor.
I actually bought the bearings off Amazon, they showed up and they were the right size, but missing the metal shield. I ended up sourcing the correct ones on eBay for $310 for the pair. Found new old stock belts for $60 for the 4 as well.
The bearings were SKF 6316 2RS1/C3 Deep Groove Ball Bearings the 2rs1 is the metal sheilds on both sides and the C3 is the grease they are packed with. There are other variations including one that has a wider heat range, but I wasnt about to spend $450 per bearing...
Not only does she chuck and duck now but she also whispers. I just have to figure out a new exhaust as the original one rusted out so its just a 4" header sticking out. Any suggestions on that?

A note on getting the fly wheel off....WOW. I used chains to secure a 30 ton bottle jack against the fly wheel to pump against the shaft. Heated the hell out of it then as it cooled it went POP. I also welded up a bracket to be able to move the massive weight away. If anyone wants to buy it let me know...will trade for an exhaust...
You placed a 30 ton bottle Jack against the flywheel, weren’t you afraid of cracking that cast iron flywheel?
 
You placed a 30 ton bottle Jack against the flywheel, weren’t you afraid of cracking that cast iron flywheel?
My flywheel isn’t cast, it’s milled steel. But to get the FW off I tried bolting chain segments to the FW then the jack pressed against the chains and shaft. not all jacks will work horizontally, the orientation matters. I left it on there for a few days tapping it, jacking it, heating it and Kroil. The jack was maxed out, broke the original 1/2” chain. Finally one day it went “booooooooooMmmp” and popped off
 
I did exactly that and yes I broke the sheave through, however now the sheave bushing is stuck. Also does that sheave bushing lined with a rubber ring around the shaft? Reason I asked I heated it and was wondering if I melted any rubber inner lining.
I don’t believe mine had rubber, a trick used in other situations- get a can of r-134a or similar refrigerant, pierce a hole in it and use it to cool down the material. (Disclaimer: don’t do this it’s bad for the environment……..)
 

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