So I've been trying to track down the source of the growl/vibration that developed on our 73 Pettibone 36mk.. It's worse when cold and when under load. I believe its one of the two main pumps, or possibly the gearbox that drives them.. so I pulled the pumps out (vickers tandems), and took a look inside, hoping to find something that stuck out, or something clearly wrong with them. Everything looks to be ok, they spin smooth and the bearings look/feel good. One of the pumps had been replaced about 18 years ago when the machine developed the same symptoms i'm experiencing now. This pump looks a bit different internally then the other one which is original, but one thing that concerned me was some significant blueing on the shaft in two spots (see pics). Any idea what caused this?? Some sort of heat treating/machining process? or could this be caused by a problem with the pump, like it ran dry and starved for oil or something? Everything else seems to be in order.. Can these pumps go bad and cause a heavy vibration and growling without having any obvious signs of a problem internally...? Shaft of pump 1.. Pump 2 shaft.. no blueing Any thoughts/ideas/experiences are welcome.
I don't know, if all the bearings are good and there's no signs of scraping on the rotary group, it would be hard for us to say what's going on with the pumps as we can't see all the components involved. Just a thought, seems if one pump got starved for oil at one point, wouldn't the other one do the same?
I would say the bluing is normal from the heat treat process. Look for chatter marks on the housing, cracks in the rotor behind the vanes and worn and eroded side plates.
That's not normal. You're right, it had been run dry. The shaft is not the same after being hot. The shaft probrably out of balance.
Ill get some more pics tomorrow.. It just seemed odd that there would be blueing just in those two spots.. Good point that they both would have run dry, but I can only imagine that, if it did run dry, it was right after it was replaced.. (the pump with the blueing is the pump that was replaced, though that was about 18 years ago) Perhaps whoever changed the pump didn't let the feed line prime and it sucked air for a bit or something..?? I can't think of any other time it would have been run dry, and this might explain why the other one doesn't show the same signs. There were some minor scores and scrapes on the side plates but didn't look too severe.. ill post a few more pics tomorrow at some point.. This is the first time i've been into one of these pumps so any input is appreciated. I pulled the inspection plate off of the gear box and disengaged it from the drive shaft.. Everything seemed to spin smooth and freely.. No metal in the oil at all.. I can't rule it out without pulling it completely out of course.
it looks as though the spots in question are both near the splines on the shaft..... is i possible that the splined areas were heat treated to harden them and that is just the result of that process?
How do the hydraulics work? Are the jerky or operate smoothly? Are you sure it a hydtaulic issue? Broken, missing line clamps, loose sheet metel fasteners, poorly routed hyd lines can transmitt vibrations and sounds thru a machine. I have spend hours chasing hyd noise around new excavators only to find the above.
Well lately the slew got really jerky.. Perhaps other operations did as well, but swing is most noticeable obviously. Its not chassis noise, or line noise.. I'm suspecting the pumps, or gearbox, because it is consistent with RPM, and hydraulic load. Also, this machine, when you first start it it wouldn't have any hydraulic pressure for a few seconds.. like if you pulled a lever, nothing would happen. Never knew why, but I guess residual pressure would bleed off and the system would have to build pressure again.. I don't know its an old machine. Anyway, If you give it some throttle you can feel/hear immediately when the system builds pressure. Now, when you feel the hydraulics build pressure, it simultaneously starts growling. In other words, its quite until the pumps have a load on them. The noise started probably about a year ago.. and has been intensifying ever since.
More pics: End plate Housing: I think this picture makes it look worse then it is.. To me, I would think this is normal wear, but again, my first time in one of these pumps. View of other endplate:
For reference, this is the machine in question.. (Not the boat, the crane!) My gut feeling, is that the condition of these pumps suggests that they are not the problem.. I have a feeling I'm gonna be putting a gear box in this thing.. I have one spare, brand new pump. I'm gonna swap that in with one of the other pumps, if the noise continues, ill swap the old pump for the other old pump (if that makes sense. (I doubt both of them are bad) ..If the noise continues Ill have to look into the gear box. The problem here is that each time I change a pump I have to pump out most of the hydraulic fluid (150 gallon tank) also, the radiator had to be removed, to get to the pumps, so I have that to deal with. Probably gonna be a time consuming diagnosis.. also expensive once it gets to the "replace parts until noise stops" stage.
I'm going to guess that the heat that turned that shaft blue was from the drive box and not the pump. I don't see anything about the pumps in your photos that would cause me any concern. It looks like the support bearing on the gear that drives that pump has failed and the pump shaft was supporting the the gear by itself. Usually the gear support bearing is in a plate that can be unbolted from the multi-drive and removed for access to the gear. I would suggest checking that out before putting the machine back together. Good Luck!
The only thing i see is on the housing pic. Is that a crack or just a reflection from your allen wrench? How is the other pump? As John suggested, check the drive box. Drain the drive box oil and see if there is any metal contamination in it.
Is this scuff marks on the rotary group? Better take a close look at the bronze shaft bushings on the end plates of that rotary.
Vickers pumps Vane pumps usually maintain efficiency and reliable operation almost until the day they poop in the bed. Never recall any noise or vibration with any failures that couldn't be directly linked to bad alignment or coupling problems. That said, because of the age of the equipment and the labor involved you could choose to rebuild or replace the pumps-every part in most Vickers vane pumps are available from vickers and usually from after market sources. More bang for your buck with the vane design. If you decide to go this route and have trouble sourcing parts you can PM me. Tom
Yeah.. I was going to check those, but to pull those plates off I have to remove the whole gear box.. I opened the inspection plate on the top of the box, disengaged the drive shaft, and spun the unit by hand. Felt smooth and quiet, but then again.. no real load on it.. I did notice a little bit of play in those drive gears, not sure how much is normal.. if any.. I drained the oil and it was totally clean.. No metal in it what so ever.
I did notice the scuffing.. Will take a closer look tomorrow..
What about oil Tell us the history of the oil you are using. Have you changed this recently? Is this the same oil that is recommended? Has there been any other recent repairs done on the hydraulic system? Perhaps the viscosity is not of the proper grade and or the oil could have water or air entrapped in it. Also did you bleed the suction line to the pump - are you sure the suction has no air trapped in it? It may also be possible that your suction line has a small air leak to it but NOT a external leak. THe oil rushing by to the suction of the pump can expose a loose or bad suction inlet o-ring or the like causing the noise and the possible damage Let us all know what fixes this as we all stand to learn something from this.
Look very closely at the bronze shaft bushings in the end plates. Look for a slight groove worn into one spot on the bushings.
Can someone help with a problem Hi I'm new to site and not sure if I'm postin in right spot but if so can someone help me I have 3 tm 250 and one has a problem with winch backing off. I bought this crane from copetown and the guy said it was certified ready for work good machine. Ha ha not even close but how ever i take machine to job a lift one section of roof trusses up 10 feet then boom up soon as I boom up winch falls 5 feet. I no eh real nice guy I bought it from tryin to kill someone if ask me. Any ideas would be great thanks. I've since learned that when winch is tight to bumper ready for travel as soon as I move out riger peddal winch will back off. Also if u tighten winch and shut motor off and start back up winch will back off. Other than that crane operates smoth and gentle since iv re powered it an actually made a crane out of it but this has got me stumped any help would be great thanks
Tm 250, Sounds like Sprague clutch in winch is not holding or it was installed backwards.
I could be wrong, perhaps I'm not looking at this correctly, but I don't think that the end plates in this pump support the shaft at all.. Like in my pic of the end plate, you'll see the center bore of the end plate is much larger then the the shaft diameter.. The shaft is supported by bronze bushings inside the the rotary housing, an inch or so from the splines.. This particular bushing doesn't look to have significant wear or damage.. There's a spiral groove cut in it for oil to flow through, aside from that, just minor wear. I haven't really been able to mess with this thing much the past few days, but tomorrow I'm going to play with it more and see what I can come up with. Ill post results tomorrow evening.
The end plates are forced by hydraulic pressure against the ends of the rotor. The rotor does show some wear spots but in the photos I didn't see any corresponding damage on any of the vanes. The rotor does not touch the inside of the ring, only the vanes do. The is a chatter pattern set in the one ring in the close up photo. I have seen that before and wonder if you can feel anything with your finger nail. If not I would think it is OK. From your description, that the gears in the multi-drive are tight I probably would think that is OK also. The growling noise could be telegraphing from some other component. You mentioned it only happened when swinging. Possibly the swing motor, the cross over reliefs or the swing reducer. Good Luck!
John, I think you misunderstood.. the growling is constant.. as soon as the hydraulics build pressure a few seconds after start up, the noise starts. It intensifies with rpm and load. I did mention however that lately the swing has become a little jerky and erratic.. I'm hoping this could have been filters perhaps, which I'm replacing, because nothing in the pumps suggest that they were performing poorly.. even If they are the source of the noise. As for the "chatter pattern" I can't really feel it..
Coalrulz Thanks for the tip with my 250 grove I would say must Be not holdin cause I don't believe that the winch has been apart in a long time. It is full of oil and it is a free fall winch thanks again any idea whare to get parts a sprage possibly and brakes
So today I ran the machine.. I installed my spare new pump, along with one old pump, the one thats in the pictures. Filled up with hydraulic oil and gave it a test. Same growling as before.. I pulled the old pump and installed the other original pump.. filled up again (all new fluid, $1,300 worth) Fired it up, this time when the system built pressure i felt a slight vibration and some noise, though this time it was a bit less severe, then after a few minutes and cycling the boom, winch, etc, the noise and vibration went away. Smooth, no growling... So, I figure that perhaps the pump was the problem, and when I started it for this last time the initial noise was just air being worked out, maybe a little pump cavitation?? I'm cautiously optimistic at this point, I think I may have it solved.. This weekend I will re install the radiator and the fixed counter weight, (had to be removed to gain access) and put a lot more time on it. Hopefully it works out..
Vickers pumps Glad you got your problem resolved-quite possible you have a bad shaft seal on that one pump. Does not have to leak oil to be able to suck air in-air entrainment will generate a lot of noise as you describe and erratic spongy operation to some functions. Tom
I put a bit more time on it this weekend after getting everything else buttoned up... Still smooth, and I was able to swing the boom a bit, which seems to be back to normal. It was real jumpy and erratic prior, so I imagine the two problems were related. Now that the hydraulics are quiet I'm beginning to hear a few other noises, ha, but I think the serious one is taken care of.
So it is fixed? Did you put new oil in it the very last time you operated the crane after you installed the "other original pump"? Was this the first time you tried with new oil? What type & viscosity grade oil are you running? Perhaps the old oil had air entrapped in it and water as well please try to shed just a little more light on this problem that I am glad you solved.
Oil didn't appear to be the problem.. It was clean and clear.. no air or water. Before I pulled the pumps I pumped out all the old oil and bought new stuff.. Can't remember what oil it is exactly but its 20wt, which is what the manual calls for above 40 degrees (being this machine lives in the boat yard, the majority of its operations are in the warmer months. Also, with the new oil, we still had the original problem on our first test. Second test problem was solved so I don't believe it was the oil.. Apparently it was the pumped that I posted pictures of that was causing the problem.
Guys I know this is an old thread but I have a few comments. I worked on industrial hydraulics equip for most part of 15 years. These vane pumps are pretty much trouble free. any wear around the rotor, for whatever reason has nothing much to do with proper operation as long as the vanes are free to move in and out. ANY wear on the rotor ends will usually prevent full pressure from developing. Pump noise (growling, whineing etc) may be caused by restriction on the inlet. The inlet strainer is more or less to protect the pump and the serious filtering is done by the system "filters". Almost ANY RESTRICTION on the inlet will cause cavitation of the pump and produce different kinds of noise. BE SURE THE INLET STRAINER/FILTER IS CLEAR AND NOT BLOCKED AT ALL. Also be sure there is no bend or crimp in the input line to the pump. Also the best piece of troubleshooting equip is A NEW KNOWN ACCURATE PRESSURE GAGE. Many pressure gages that are left in the circuit will not be accurate and may cause you to have pressure or speed operating problems. Been there got the shirt. Taught Hydraulics/pneumatics for ten years and always told my students to buy/steal get by any means a good new accurate gage. Keep it in your tool box and use it to replace old gages TO BE SURE. These gages take a pounding and you can hear the beating they take by putting a screwdriver to the gage and to your ear while it is operating and check em out. Some gages have a valve so you can cut them out of the circuit when not needed to save them from this pounding. Hope this is good info and I know it is an old thread but had to add my 2centavos ...... Check your gages while the equip is shut off and see that they do read ZERO. If there is a pin there to stop the gage from reading lower.......PUT IN A GOOD NEW GAGE FOR SURE.......JUST DO IT.
i had an ongoing issue with a 633D scraper doing a similar thing, turned out to be a split return elbow inside the hyd tank under the filter housing causing the oil the airate and cause cavation like syntoms I've alot had a "rebuilt" vane pump from a hyd shop be very noisey, after going through all the steps like above ended up stripping the pump and finding the vanes in around the wrong way! trust noone
Good to know.. However, in this case the feed lines are very heavy 4 inch hose that would be nearly impossible to put any significant bend in, let alone a kink or crimp.. I never touched any strainer between the pump and the tank.. In the end, replacing the pump ultimately solved the problem. We have about 125 hours on the machine since replacing the pump and no issues (knock on wood).
Good news guy. Glad you found the problem. I wish I knew what the problem was with the pump. Aways good to file that info away for later reference.