Chipper question...

Bermy

Acolyte of the short bar
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Tasmania
I know its not a chainsaw, but still machinery...

We have been running the chipper quite a bit lately, for a good few hrs at a time. Yesterday at shut down after about 2 hrs, Bob realized the hydraulic motor/bearing' on the feed roller was hot, like almost too hot to touch, all the other bearings were warm, but not too much, about what you would expect for running it continuously for a couple hrs.

The fluid is topped up, filters got changed last year...no obvious leaks, just a bit of oily moisture around the fitting where the hoses head under the chassis towards the oil tank...

Any suggestions? Is running it that long at one time too long?
My chipper is second hand and the manual I was able to coerce out of the manufacturer is not very detailed.
 
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All greasy greased, no out of the ordinary noises...Chipstar 150MX, Australian made. (2002)
 
I am guessing the hydraulic motor is going out. Most of them are fairly standard, most chipper manufacturers do not design and make custom hydraulic motors so you should be able to find one 'on the shelf' somewhere.

I would not do anything with it yet, just know it is wearing out. I would begin researching it and trying to source a replacement, either new or rebuilt. Or even a local shop that rebuilds hydraulic motors. Do your homework now so that when it does eventually quit working you can replace it and get back to work quickly and cheaply.
 
I would not worry too much about it. The bearings will get warm with use and the pump will get hot with use. Possibly clean out the hydro oil cooler fins with compressed air or a pressure washer, once the unit is cold. Do the same with the radiator, often. Always a good idea to change any and all filters more often than not chippers love to produce dust. When the chipper is shut down and the cutter drum/wheel is free spinning listen for any odd sounds like grinding or chirping. You want to hear a smooth even sound if anything.
 
A wooden dowel on pressed on the bearing housing and the other end in your ear while the feed is running will let you hear crunchy bearings over the chipper noise.
 
I have done that listening thing with a long screwdriver...put the handle end in your ear...not the other end....just sayin':D
 
:lol: @ Gary.

Look at the brand on the motor as well. I had my drive motor that went bad on my dingo rebuilt with warranty for about 1/2 of the cost of new. Call around. I saved like 450.00. Well worth the 1.5 hour drive.
The dowel or screw driver trick for bearing noise is good advise.
 
Yup. They make actual stethoscope kinds too, and are cheap enough to justify having. Good for all sorts of diagnosing tasks.
 
I had a similar issue with one of mine, I just ignored it, nothing happened,it was normal.

Hydraulic motors are very durable, I’ve never had one let go.
 
Well they do go out at times that's for certain. I've had a couple go and being around machinery lots I've seen/heard of it many times.
 
Yup. They make actual stethoscope kinds too, and are cheap enough to justify having. Good for all sorts of diagnosing tasks.

I picked up one of these cheap like $10 at Napa in the bargain. Well worth picking up as Kyle said.
 
Well they do go out at times that's for certain. I've had a couple go and being around machinery lots I've seen/heard of it many times.

Fair enough, in Bermy’s situation what would you do? I had the same on a chipper a couple years back, Ed (Thor’s Hammer) late of this parish said to turn the rollers to top speed to ensure the oil flowed as quickly as poss.

The oil can get hot, it’s not an issue.

(Interested to be schooled on this by the experts, not a hill I want to die on you understand)
 
IMO if it is going bad run it until the bitter end you are going to have to replace it anyways so why not make a few more dollars first.
 
I am guessing the hydraulic motor is going out. Most of them are fairly standard, most chipper manufacturers do not design and make custom hydraulic motors so you should be able to find one 'on the shelf' somewhere.

I would not do anything with it yet, just know it is wearing out. I would begin researching it and trying to source a replacement, either new or rebuilt. Or even a local shop that rebuilds hydraulic motors. Do your homework now so that when it does eventually quit working you can replace it and get back to work quickly and cheaply.

Brian nailed the best course of action IMO. But I agree they can get quite hot just during normal operation. Better if you have more than one hydro motor running on the same fluid so you can compare. I'd zap it with a infrared thermometer and see just how hot it's getting and check it now and then if it was concerning to me. I've noticed a infrared thermometer is how all of the drive motors at the mill are checked, quite regularly, I suspect daily from the amount of times I've seen a millwright doing it at my work station/machine.
 
To answer your question about how long a chipper should be able to run and not be too hot Fiona it is continually. Well, with shut downs for grease at 8 hrs or whatever your manual says and refueling.

Too hot to touch on bearings would be indicative of problems coming on my chippers but there may be a possible exception if a hydro motor was closely attached to it and especially if in really hot weather. I would try to ascertain where most heat comes from by touch.

Listening trick sounds good, and getting a bearing or motor sourced before failure - if it ever fails.

A point of interest is that some bearings are made to take excess grease and let it flow through purging the old grease, while some are sealed and only meant to take a little as replacement for a small amount that weeps out. (If I understand the difference correctly. )
 
One problem when a hydraulic motor goes bad is the flow of metallic dust or even chips sent through the hydraulic circuit. The filter (if there is one) takes care of part of that, but not all. Plus some of the valves and distributors are still in the direct way (before the filter) and that's not good at all for their own function and service life.
Avoiding the oil contamination is a big thing in hydraulic.
It isn't a good advice to run it until it dies because that can lead to a way more costly / complex repair and more down time.

At least, check it out to estimate the internal wear.
 
I would not worry too much about it. The bearings will get warm with use and the pump will get hot with use. Possibly clean out the hydro oil cooler fins with compressed air or a pressure washer, once the unit is cold. Do the same with the radiator, often. Always a good idea to change any and all filters more often than not chippers love to produce dust. When the chipper is shut down and the cutter drum/wheel is free spinning listen for any odd sounds like grinding or chirping. You want to hear a smooth even sound if anything.

One hot, one warm seems to be an indicator of something amiss.

A stitch in time, saves 9.
 
True, but I have never had a hydro pump I could put my bare hand on after a few hours of running, bearings yes but barely. IMO the bearings getting warm/hot is from the friction of the wood being chipped not necessarily bad bearings. The drum/wheel heats up and heat transfers down the shaft to the bearings. If you were to smell something cooking that's a different issue and a sure sign something is shot.
 
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