HVAC Questions? Ask an HVAC Expert for Answers ASAP
by wheel do you mean pulley for a belt?
If so yes, here are the things to check, if there is a belt, replace it, even if you have to go generic, it has a size and length, Skates belting or a belting company can get you one, if you have a ridge on the inside of the pulley, the pulley is worn out, causing the belt to slip, as the cut in the pulley is worn out, replace pulley, next, the pulley could have a bearing, for get replacing just the bearing even with no ridge, just to make it work as best it can, replace the entire pulley and bearing assembly, next is there an idler bearing, for tightness of the belt, if so replace it,
you get the rattle, if available get a new cage if it is that kind of setup, squirrel cage is what they are called and commonly the motor shaft is in the bore of the wheel, if the bearings are worn out in the motor the fan is dull and not cutting air like it should, replace the whole thing, I always replace motor and fan, or motor and pulley, get the most efficient setup you can, and repair it once,
This particular setup is a motor with a pin that goes into a squirrel cage - a two-piece setup. We're getting heat, but the air isn't blowing as strong as it should because of the squirrel cage rattling.
That I am afraid is not good, get a new wheel ordered if available ASAP and do not run this one but just enough to get by, what happened is like I said the bore of the wheel is oversized and even worse you have a pin instead of a set screw or something to tighten you gotta line it up and slide the pin in, so the cage is rattling around on the motor shaft, and right now it is tearing the bearings up in the new motor with the hammering from this looseness, you can use it, but sparingly, don't freeze or get too hot, but get a new wheel, also the wheel being loose on the shaft, causes the cage to spin in a non uniform manner, which creates turbulence of the air, and that is not good either, and also the amount of air, it could very well be the looseness of the cage on the motor shaft, but just for grins, they are identical, sometimes motors are replaced with multi speed motors and the user has to pick which speed, but with a pin, and you got that in, it is probably the same RPM, and all that, I worry about squirrel cage setups, most do not understand without restriction on the intake side of a cage blower, this is a blower not a fan, and with nothing restricting it, it will actually try and suck all the air out of the world, the way to tune them in, is to use a clamp on amp meter and start doing your return plumbing until the amps match the motor amps, then you got a near perfect situation but right now you are in need of a new cage bad, the new one might be tight, they make these things with a tolerance or a few thousandths of an inch, if you are near size for size on the new motor shaft say it is on the big side of the tolerance and the cage is on the small side of the tolerance it could be near size for size where it would need to be sweated on, so if it is a tight fit, talk to me first, we need a bronze or soft material sleeve to push the new cage on the motor, we do NOT WANT TO BEAT IT ON, if it needs to be forced something is not right, so stop, that is worst case, most likely it will go right on, got some anti seize compound laying around? that would keep the cage from rusting or sticking to the motor shaft next time it fails, and make it slick to get on, if you need it, you can use light oil or even use Crisco oil to wipe on the motor shaft for a lube to get the cage on if tight, just do NOT BEAT on it, now maybe you don't beat on stuff but don't be mad at me, way too many do beat on stuff, so I have to make sure, if you don't beat, then that message is not for you,
Let me know how it goes, and remember when changing out a motor usually the driven end is worn somewhere, if the driver is worn, the rest is just as old and has as many hours so always try and change out most moving parts, if not real expensive, if a few bucks for a bearing here and there, makes it all new, do it,
If you cannot get a new cage we have options, maybe, first if you have a small local machine shop if there is enough material left in the bore of the old cage he might be able to machine you a sleeve to reclaim the bore, shouldn't be a huge deal to do, another thing is he could knurl the shaft, that is a process which puts many "tits" on the shaft and they expand, holding the over sized cage tight, but you want to knurl it not use a pin punch and start making pot marks on the motor shaft unevenly, that is not good,
a knurling tool is like two wheels with spikes on both, it is clamped in a lathe tool holder, then the motor rotor is centered up in the chuck jaws, then the knurling tool is pressed against the shaft giving it a bunch of tiny spikes to tighten it up
Ok, so just to confirm - the rattling is from the cage not fitting on the motor shaft correctly, so get a new cage before it tears up the motor shaft and worse the motor
Is it possible to get a sleeve for this motor shaft and save the wheel? Would this be a less-expensive option, or am I best off getting a new wheel?
I doubt they have sleeves pre made, the cage should not be expensive anyway, PLUS you get some more benefits, you get a new wheel that has sharp brand new air scoops, they do wear dull over time and don't move as much air, plus it is factory balanced on a mandrel, so wherever you put in on the shaft, it is in balance, plus it will cost less to move more air, now you wouldn't think that made much of a deal, but electric motors as efficient as they are, use the most power in most all homes, there are exceptions but your vanilla home the fridge, freezer, dish washer, fans, blowers are the energy users, so just get a new factory wheel from where you got the motor, they should have it if they had that furnace motor, NOW if they come back with some out of this world price, let me know, but if it is $100 or less, go so we can get it in and do a test run, while we have a connection, I think you can find me or ask for me but not sure, how to do that, but I will keep it open on my end not the chat window, but the question, and wait for you to tell me how much for the wheel, we can get it, and we can test it, never know if might make another noise, but I am sure this will take care of your main problem, I just want to know you have a stable furnace before it starts getting colder and colder, so let me know, Will
http://www.mhparts.com/coleman-evcon.php?pg=2 the prices for and Evcon are on the last link, they had three but no way to put in exact model says call them so you would have to do that, but I wanted to get you some prices so we know we are in the ballpark, they run $63 to $97 so not bad, not great but not bad, a machinist would take 2 hours to bore the existing unit out so a sleeve would fit, then build by machining a sleeve to size, and the pressing it in, if everything went slick, so you would be talking maybe $150 or so for labor and then a little for parts, so cheaper to get the new blower, also if it was done in my shop we would balance it on mandrel in a stand, and if a machine shop around here did it, they would bring it to us,
I will look some more and see if I can get this DG number to pop up exactly, sorry I didn't back earlier I got real sick to my stomach for some unknown reason this am, and it was bad, I finally kind of slept a little and it now feels shaky but ok
http://www.expertappliance.com/partfinder.php well here is your wheel at this place but $164 !!!!!!!!!!!!!! Shop more, it either a really nice heavy built blower wheel or they are marking up to the public something awful I will keep looking too, also try Graingers and Johnstones Supply, some places will sell them with the dimensions, you give them the length and so on, and those are just as good,
http://www.furnaceparts.com/Store/Category/blower%20wheel.aspx these look better but you best call them,
keep in touch if you need anything, Will
di you find a new wheel? I got a bad case of stomach flu and just now can sit up and work the computer it was bad, so how is the hunt for a new wheel going, ???
I have found a new wheel, and am waiting for its arrival. We shouldn't need to balance it on the shaft of this motor, correct? Shouldn't it fit and balance properly upon receipt and installation? Sorry to hear you have had the stomach flu! Thanks for keeping the messaging open for me - I can sure use any help we can get! Hubby and I looked at the existing wheel while it was running the other night and it's definitely out of balance. Why we wouldn't have noticed that with the old motor doesn't make a whole lot of sense to me, but I'm an accountant not a mechanic. He's the handy man ;-)
No problem, the reason it probably didn't look out of balance is there is less slop in the fit now, [still slop but not as much], now one thing that comment brings up is important, it is the SAME SPEED right? Now as far as balance the new wheel should have been manufactured and balanced on a balanced mandrel, so no matter what it is put on, as long as it is put on a balanced and straight shaft it should be just fine, the speed of a furnace should be 1100 rpm or less, rarely above 1200, just worth checking if possible, but no panic needed, the biggest thing we have in front of us in getting the new wheel on the new shaft, it could be tight, remember no beating, we will get it on there right, and I will keep this open as long as it takes, and yes I was sick, all of a sudden but feeling better today, a bit at a time, thanks for asking, Will
Thanks again. The motor is identical, so yes, it is the same speed. Just waiting for the new wheel now. Was hoping it would be here today, but it's not yet - hopefully tomorrow! Top speed was either 1000 or 1100 - single speed motor.
Perfect, on thing to check while you are waiting, the motor is probably mounted in what is called a "cradle mount" where there are two isolators on each end, or there is a three bolt clamp, which holds the motor up by one end, on the cage. I cannot tell on your model which way it is, but you can check while you are waiting to make sure none of the rubber isolators are hardened or cracked, letting the motor flex. It used to be that a new motor for a blower came with the mounting pads, whatever type, but this day and age hard to say. Just something to check for if you have not already. I know my Trane was a real bear it quit on a Saturday Morning and no kidding, 16 degrees, my Daughter was like 5 and my Son was one, it was an OEM motor, special connector on the power end, nothing open, so I went to my shop and built a Frankenstein Monster, cut the special connector off the end, and hard wired it to a generic motor that is still in there today. I got by for about a week before I needed the new wheel, it wobbled but did not strike, so I ordered it on Monday and next weekend took it all back out and replaced the wheel.
Another trick you can use in an emergency is to get some really thick black grease, and pack it around the shaft, slide the old wheel on and it will self adjust most of the time for a while. If you have any shaking which appears to be unbalance, look to the mountings.
The balance clips are just slid on the louvers so make sure not to move them. Remember when you are looking at the wheel in the cage, you have the restriction plate off and air turbulence will make it look worse than it is. Balance and alignment are two concepts that are very hard to explain. If the wheel is running in out of center and has a wobble, that is not necessarily balance. If you need to do anything else, it will be to tighten the bolts a little a time to get the motor hanging in the middle the best you can. This will not be a precision perfectly round perfectly orbital motion by eye, but it should not shake. Some wheels have a natural frequency on the way up and down, that matches the duct work and gives a half second hum, but that is normal. They build this stuff cheap and want a fortune for it.. But from what you described, I am 90% positive the wheel to shaft is too loose. Take a look at all the grommets, if they did not supply them new, and make sure none are cracked or hardened, and don't over tighten them. They are isolators and should have some tire shape to them. Past that I am sure you will be fine. It does take a little patience to get it all up in there, and again this is not a 737 turbine blade so don't expect perfection. It should not shake violently and it should never touch. The rest is pinned so no adjustment there. You might get you flashlight and look the cage over for any cracked welds or anything out of place. Just trying to think ahead. Most of these go back with new motor and wheel with no problem, I found no recall or call for change out of the cage, on this model so it should be fine.Wish you lived down the street and I would be over and help you get this back together. Just let me know how it goes, and we will get it going.
See the three bolt mount, that should be like yours, the only other way is a cradle mount motor with two clips that hold the motor in the cradle on either end. You want to make sure you don't squeeze those mounting isolators, you tighten them a little a time and spin the wheel by hand, [make sure you have the BREAKER OFF< there may be an off/on switch right there, and as you tighten the bolts, spin the wheel, and you can tell if you are pulling it up or cocking it, it really should not be a huge process.................... just trying to stay ahead of things in case anything does not act the way you want.
Would you believe the supplier "forgot" to ship the squirrel cage? We called on Thursday and they said they'd ship 2nd day air, no extra charge, and I should have it on Monday. Thought I'd keep you posted.
their "special OEM motor" nothing more than an unnecessary plastic connector on the leads, which is a problem for the home owner who is normally not going to take a pair of side cutters to the end, and wire the motor up with wire nuts, just drives me nuts, anything to keep the customer coming back and at their mercy. I don't have a problem with a company keeping their parts in house, but to modify it and then mark it up from a $40.00 motor to a $400.00 motor, is not profit, that is lack of ethics and why businesses feed reasons to our wild left, to have a legit complaint. Sure if they invented something that saved you some money, improved on something, did SOMETHING besides taking a standard motor and putting a gun to your head, I could understand the value, but the lack of ethics, knowing they have most users by the nap of the neck, when it is freezing outside, is just plain bad business. Thanks for letting me know, I was beginning to worry about you, it is supposed to get cold here, next week, real cold, don't know about your area but I would be much happier knowing you were in good shape and worry free, so keep after me when it comes in, if anything gets to be a problem we will get it taken care of, by the way, unfortunately we are not allowed to contact customers directly [I understand they don't want experts making deals with customers, fair enough] but I do check my email on Holidays, weekends whenever a problem could be a huge problem, so if anything comes up, just keep sending me a few notes I will find them, actually I think they pretty much trust me, I have had opportunities to go around them, but that is not my way of doing things, read my bio and with a little figuring you can probably find my personal address, which I have no problem answering if a critical situation needs attention, I will be checking Christmas Eve, Christmas Day, for those who end up with problems of toys not working or assembly issues, from 30 years in the service business, I have worked every Holiday, more than once, spent Christmas Eve, Day, in power plants, nursing homes, whatever, part of the deal, appreciate you letting me know they "forgot" to ship your part, truth be known, NO ONE is stocking much of anything, right now, and my guess is there was no wheel to ship, or they had to dig one out of some warehouse somewhere, or even buy it from a competitor, I will sure be glad when things get back to more normal commerce, a little confidence, and a brighter outlook, I think it is coming, but it sure is taking a long time, people are hurting so bad in some cases, it really is a sad situation, but we will get it all worked out, now we finally woke the hell up,,,,,,,,, talk soon, Will
Good afternoon, Will; the wheel finally came last night. Hubby tried to get the old wheel off of the shaft this morning and it's not budging. Said that it moved position - we assume because of the vibrations over a week of having to run it as it was to keep from freezing our hineys off. He's going to wait until I'm home to do anything further on it.
OK , well no panic, tell me if I am wrong but I was under the impression it was pinned, to me pinned means a roll pin, through a shaft, usually in front or behind a flat washer. Not unusual but not as typical as most residential blower wheels. The wheels I looked at for your model number had a square head bolt, that would mean threads in the wheel shaft, the bolt screws into the threads and then into either a flat on the motor shaft, or an indention in the motor shaft. Common trick, which gets a lot of people in trouble, is the double set screw. THe manufacturer will put a short set screw in first, down the threads into the motor shaft, THEN they will put a SECOND set screw on top of the first, to double lock the set screw from backing out, but because you have had this wheel off, you would have found that, as when it is not found, what happens is the victim removes the top set screw, is unaware of the lower screw, and puts a set of pullers on the wheel or whatever device and begins to pull the wheel off by using the pullers, the pullers push the shaft and grasp the outside or inside of a wheel or coupling half, with enough force, it usually comes off, but the lower set screw drags right down the shaft, making a mess of things, that is for future reference, because I know you would have seen it installing this new motor, and old wheel.
I was mistaken. It has a set screw. Hubby set me straight.
Fortunately it is only one set screw.
Now the question is, how difficult was it to get the old wheel on the new motor shaft? I think I explained tolerances, if the motor shaft was on the large side of the tolerance it could be .001 to .002 on the large side, the bore of the wheel could be on the small side, meaning the opening could be another .001 to .002 on the small side, add that up and you have four thousandths of possible interference, or size for size when measured by a micrometer, meaning one tight fit. If this happens, usually the outside component is warmed to about 225 F to swell it, and let is slide on the shaft, or dry ice is used to shrink the shaft, either way or both,, but I cannot imagine that the tolerances are that tight on this, most of this stuff is pretty much sloppy if anything, and it would not surprise me if the new wheel ran out, where it was even visible to the naked eye, but that is not really important, if the fit on the shaft is close enough that it is reasonable, and not flopping around on the shaft,
He said it wasn't hard.
He had to push on it, but didn't have to force it.
When you have a tire balanced most wheels on your car are not true, they run out by quite a bit, then add a tire, and you have a bit of run out overall, so the balance guy, makes up for the run out by using weight, to keep things as smooth as possible, yea the world is full of half baked half done right stuff, What concerns me is even though the wheel has been running out pretty bad for a week or so, it takes a while to gall a shaft to a bore, what I think you have, is simply the most common problem, and that is the bore of the old wheel was never straight, from day one, it was removed, it was replaced, it is now even more out of center than before, no big deal, just patience, plus unless he has the entire cage out on a workbench, and I would absolutely recommend if you can slide the blower assembly out, even if you have to cut wires in two pieces and wire nut them back together, because of a special plastic connector, cut em in two, and get the cage out where you can get to it, most are just a bear to work on, standing on your head, or trying to lay and reach the blower,
He does have it out. Can't really work in that unit without taking that whole big unit that looks like a snail shell out.
next comes the patience part, it will probably take a lot of walking a few thou at a time to get the wheel off the shaft, walk it by one side and then the other and back and forth, it will come, make sure we have all the pins and any set screws out, trust me, I have pulled on things for hours and realized I was pulling against something I PUT IN!!!!!!!!!!! Very frustrating, it would also be nice to have the cage on a work bench or table to run it without the wheel and see if you can see any run out in the motor shaft itself, this usually takes a dial indicator, but if you can see a 3/8 to 1/2 inch diameter shaft, run and not be running straight, with the naked eye, that shaft is bent, and we will have to deal with it, dependent on how much, they send motor shafts out running out all over the place, and then with the slightest bump or bang, they are that much worse, but it may be a huge job to get that blower assembly out, I cannot tell from the breakdown, but most I have managed to get out, I like to get the blower out, get it running nice with RESTRICTION ON THE INCOMING SIDE< then I move the wheel to where my amps are right on the name plate, tighten it down and that is as good as it can possibly get.
I assume the motor would run with the wheel off - if I can have him run the fan so we can tell if the shaft is bent my guess is we'll be half way there. The trick is getting that wheel off.
But for only two weeks, it may seem welded on, but it is not, it is just frustrating, nerve wracking and all kinds of thoughts of freezing to death don't help, been there, so relax, there is a way, and I won't leave you until we are in good shape, so I will make sure I check on you through the night or until you tell me something different, right now I am trying to make my damn camera put pictures on my computer, done it a million times, and now it seems to not want to recognize my camera, MICROSOFT< now there is a blood pressure problem right there, so frustrating to go back to something you have done a million times, and now the driver is not right, or the old driver has not been deleted completed, nothing should be this hard to fuss with a damn picture, anyway, your furnace is much more important so I will be here, and if he feels like it, fine, if not we will do it later, whatever you guys tell me, just remember you got me to ask or help or whatever you need, I will sure do anything and everything I can to get this going with you, we used to be a FASCO motor distributor, and you would not believe the thousands and thousands and thousands of combinations of motors and speeds and mountings , unreal all the different ways these things are put together, so we will figure it out, just let me know as you go along if ANYTHING at all, no matter what, is a concern, let me know and we will hash it out, I will be around, just drop me a note, Will
Will, thanks for everything - it took patience to get the new wheel on right - getting the old one off wasn't too bad - used a convertible screwdriver and a hammer to knock the motor out. We were concerned that the new wheel was a bit wobbly when we spun it by hand, but when we turned on the furnace it was peaceful and quiet!! IT WORKS!!! Thank you so much for everything... and if you don't mind I'd like to keep your contact info just in case something else happens.
By the way, my name isXXXXX in the event you hear from me again ;-) Thanks again for all your help!
I'm going to keep this open for another day or two just in case, but I have a feeling I won't need to!
Yea, I got back on here later than I thought a good friend's Father passed today and I just got the news as I left you the last message, yea that is why I didn't want you to worry if it wobbled a bit, hard to say what a "bit" is but when you said rattling AND squeaking it was a great description and I was pretty sure what we had, take your time and I will leave this open and will check from time to time, but if you have a nice whoosh now, it should stay that way for a long long time, one thing you might do, it probably will never be needed, but if you wrote down where you got the parts or stuck the paperwork with the furnace paperwork or under it, if for some reason, storm . whatever and would happen to take the motor out, it is a quick reference relying on them being in business, but better than nothing, for a quick start in a jam, great news, I needed to hear that something worked out today, good for you, and the air will move with less force it won't lower your bill to nothing but it will help, good job guys! Let me know if you ever need anything, I have done mechanical and electrical everything, from antiques to electronics for decades, not much I haven't figured out, one way or the other, good news and good job Will