RedMaine 1 #1 Posted February 1, 2015 My 520xi mounted snowblower is vibrating like crazy. The collars on the jack shaft both came loose and cracked. I pulled the front half of the unit apart after taking the chain off and the jack shaft feels smooth and has no lateral movement. I noticed my chain is very stiff and worn on one inside edge. My impeller was bent a few years ago and I did my best to straighten it out on the maching. I didn't have a wheel puller and could not pull the sprocket fron the impeller shaft. It is my belief that the impeller is still bent enough that it is way out of balance.. could that be causing the vibration? Could the chain be causing the vibration? The chain was very loose. The vibration is so severe that the drive pully is coming loose and dropping its key. I have to tighten the set screws very tight and that makes me nervous. There is a very light bend in th ejack shaft as the pully does move very slightly up and down while rotating.. Any ideas? Where to start, what to eliminate? I think the blower has maybe 25 hours on it since new. Thanks!! Mark Share this post Link to post Share on other sites
JERSEYHAWG / Glenn 4,487 #2 Posted February 1, 2015 Is it a single or 2 stage? With the high revs of that blower it sounds to me you put it back together "without" really fixing the problem. Stuff bent and now its literally shaking itself apart. No good. Straight and balance are 2 very important parts of that blower. Lets here how others chime in,,,,dam shame on something with so few hours. One step at a time. Fwiw,,,,I would not run it anymore till its repaired. Glenn 1 Share this post Link to post Share on other sites
shallowwatersailor 3,213 #3 Posted February 1, 2015 (edited) I'm not sure if you have a single-stage or two-stage unit. I had to replace the outside bearing on my new-to-me single stage snowthrower this year. There was a lot of vertical movement inside the flanges on the chain side with the outer case of the bearing actually turning. I assumed that the bearing had gone bad. It also appeared as if it had been taken apart previously. After pulling it apart, I found that the bearing actually was bad (dry and gravelly) - but the flanges had been assembled wrong. Logic has it that the flanges would go on either side of of the housing. But that is not correct. Both flanges need to go on the same side and are bolted to only one side of the housing. The bearing on the belt side had been assembled the same way. I ended up pulling the whole jackshaft out and reassembling it. The only thing I changed is the location of the flange with the zerk fitting is now outside contrary to the parts drawing. Before I pulled it apart I did notice that the chain was not running true to the auger. I replaced the chain and idler pulley at the same time. Now everything running is in line. That may be why you chain has wear on one side. The last picture is the old and new chain with the same number of links but showing how the old has stretched. Before with just one flange. You can see the grease bath it was running in. After showing the two flanges on the same side. Chain comparison: Edited February 1, 2015 by shallowwatersailor 2 Share this post Link to post Share on other sites
Rick_in_CT 156 #4 Posted February 1, 2015 Mark, I just sold my two stage, but I have plenty experience with them. Not sure why the collars on the bearings would crack, are you sure the eccentric locking rings were tight when the bearings were last installed? The fan does not really turn all that fast, so unless you can really see that it is plain bent, I don't think that you are going to get a good vibration from it. You state that it is vibrating like crazy, would you say that the vibration frequency is pretty fast, or is it slow. If it is fast, I would be more suspect of the chain drive and its related components. Check that the bearings in the sprockets are free and well greased. These are not sealed bearings, and you can force some grease into them. The chain also needs to be well lubricated, and the links need to freely bend. If the chain is not good, replace it. You can get a 10 foot length of #40 chain at the hardware store. The length of my chain was 46 links, not counting the master link. Each link was counted as one full dog bone. I aligned the sprockets by using a straight edge across the face of two sprockets at a time to make sure that they are all on the same plane. The chain tension can really create a wicked vibration if not correct, plus it will give you an audible roar if incorrectly tensioned. The following is from the operator manual, copy is attached. Verify the Drive Chain Tension Verify that the drive chain has between 1/8†and 1/2†deflection in the area shown in Figure 4. If the chain is too tight or too loose, adjust it; refer to Adjusting Drive Chain Tension, page 21. If everything rotates freely by hand, and there are no noises when rotating by hand, I would check the sprocket alignment, chain quality, and then play with the chain tension to see if you can get rid of the vibration. Also check the bearings in the four V-belt pulleys in the carrier. Let us know what you find, and if you have any more questions. I'm looking to see if I have some additional pictures I can send you. Rick 522xi Snow Blower Operator Manual.pdf 2 Share this post Link to post Share on other sites
Forest Road 594 #5 Posted February 2, 2015 I rebuilt my 2 stage a few years ago. A bent impeller shouldn't cause a crazy amount of vibration. A bent or severely worn chain and sprockets will. It's money well spent to replace the chain every couple of years. Before it starts to show any wear. If the chain & sprockets are worn they definitely need to be replaced. If any of them are bent you're certain to have vibrations. New idler as well. When was the last time you greased the impeller bearing? How worn are the auger support bushings? Might be time for a full rebuild. Good luck 1 Share this post Link to post Share on other sites
RedMaine 1 #6 Posted February 2, 2015 Wow! Thanks for all the thoughts.. It is a 2 stage.. and I pulled the front (the 8 bolts) off, after disconnecting the chain. Well, that was eye opening.. the chain is shot.. many links were frozen and even after a bath of pnetrating oil, the chain stil lhas issues.. So, that will be replaced.. Second, the jack shaft is turning freely and has no issues.. Must have been the chain causing the vibration. While the front was off I could feel that the impeller and its bearing spun freely.. I am ordering a new chain today.. #40 Rick, my blower should have 46 links? I willcertainly count them before getting it.. Also, I think the alignment is not perfect, and the chain was wearing on one inside edge. The sprockets all look fine. No noticible wear. After pulling it all apart and expecting a foot of new snow today, I put it back together (with the lubed old chain) and re-adjusted the tension. It felt a hundred times better. But still needs a new chain. Thanks for the help and confirmation!! Share this post Link to post Share on other sites
Rick_in_CT 156 #7 Posted February 2, 2015 Mark, It was good to speak with you this morning. I think you are on the right track with the new chain. Attached is the complete parts listing. Good Luck, 522xi Snow Blower Parts Manual.pdf Share this post Link to post Share on other sites
Forest Road 594 #8 Posted February 2, 2015 Your sprockets should have broad clearly machined tips. If they have sharp ice pick like tips they're shot. My blower is on a 314h. Same blower different mounts. It has a nylon block for chain tension. Some members have replaced that with an idler sprocket. It's also on my list . 1 Share this post Link to post Share on other sites
RedMaine 1 #9 Posted February 2, 2015 I ordered 10' of #40 roller chain from amazon along with a breaker and a few master links. We got another foot of snow, and it is snowing till late tonight. When that is done, and the chain is here, I'll examine the sprockets.. I am fairly sure they are not pointed. Maybe I can take some pictures and post them.. Thanks for all your help. 1 Share this post Link to post Share on other sites
RedMaine 1 #10 Posted February 4, 2015 OK.. got the chain and aligned the sprockets.. WOW! they were WAY OFF!!! how does that happen?? Anyway.. hereare the before and after pics.. Share this post Link to post Share on other sites
Rick_in_CT 156 #11 Posted February 5, 2015 Mark, It looks like the upper jack shaft had moved forward towards the blower housing. This would happen if the collars on two bearings came loose. I compared your pictures to some that I have and the gap between the top sprocket hub and the bearing are greater on yours than what I had. On mine the hub was pretty close to the bearing. If the jack shaft moves in, it is also moving the v-belt pulley in, which you don't want to happen either. Your pictures after the re-alignment look much better. If everything is locked down, I think you will be in much better shape and it should be quitter. If it was running with that miss-alignment, it should have been pretty loud. It wouldn't be to long before some expensive damage was done. Let us know how it works once you get the chain on it. Rick Share this post Link to post Share on other sites
Rick_in_CT 156 #12 Posted February 5, 2015 Mark, I wanted to double check with you on the bearings on the upper jack shaft. Are you familiar with the eccentric locking collars on these bearings? Before you tighten down on the set screw in the collar you have to rotate the black collar in the direction that the shaft rotates until the collar tightens up, then you rotate the shaft until the drilled pilot hole/dimple in the collar comes up top, then using a drift pin or similar at an angle, you drive the collar tighter using the drift pin and a hammer. This is to snug up the eccentric. Once snug, you then tighten down the set screw. It is best to use some Loctite on the set screw. Use a hand breakable Loctite, like threadlocker blue. When you want to remove these bearings you loosen the set screw, then using the punch you drive the collar in the opposite direction of the shaft rotation. Just wanted to confirm that you have the bearings correctly locked down to prevent that shaft from moving in the future. Rick Share this post Link to post Share on other sites
