G'day, I have a Grove MZ66B - I have been going through the process of trying to get it operating better. I have also been trying to check the lubricant levels/condition. Please see below two photos of the drive motor for the turntable. One photo is closer than the other. Is the plug at the top under the elbow in the pipe the filler hole for the gear oil in the drive motor???? Are the other two screws which are parallel with one another - just like fill and drain holes on a vertical drive motor used as the drain holes??? It seems to me that they would not be low enough to drain the oil??? Thanks for any help, MX45.
Cant get 2nd photo to attach? Anyway there is a second 'plug' screw further behind the cylindrical drive motor at the same level with evidence of faint oil weepage. Thanks again for any help.
SWING MOTOR HELP - I opened the filler plug and the stench that came from there may have been oil at some time but just sludge now - I am judging by the odour and the thickness that the oil has not been changed in the 3000 hrs or so the machine has done. I tried to use my sump pump to suction the oil out but the copper pick up tube would not fit with the angles and plastic tube as at first too big and then when I did get a section of nylon air line in to use as a suction pick up it would not go far enough - go 300cc out of what is meant to be a litre - maybe there was only 300cc left but I dont know. IN any event the nylon line got caught on something and snapped on the way out. In my attempt to get the remainder out it irretrievably went back in. I guess it was always a good idea to split the gearcase and wash it out now it is even more necessary. Does anyone reading this know if those twelve bolt head with half inch sized heads are what retain the hydraulic motor and top plate cover to the gearbox??? I expect it would have a gear affixed to the bottom of the hydraulic drive and should simply unbolt and then I can remove it to the side and have access to the gear box from above to clean it thoroughly and retrieve that plastic tube and probably 15 years of gunk and no servicing????? Are there any catches to pulling this apart anyone knows about???????????????? Anyone????????????????? Thanks for any assistance to guide me through this, MX45 Can any of the supervisors rename my thread to swing motor - better suits my needs.
I changed your thread title as you requested MX45. Yes, that pipe plug is the rotation planetary gearbox oil level plug. Would also be used to fill gearbox to that level by removing one of the opposite plugs, fit oil hose to one of the open plug holes, and fill gearbox until oil comes out opposite plug hole. You have no access to the drain plug with unit fitted to machine as drain plug is in the very bottom of the unit if it has one at all. As for cleaning the old oil from the planetary box, you would have to remove the unit from the machine. I can't recall for certain where the rotation gearbox was located on the MZ66, seems I recall it was in one of the side door compartments and not in the center of the machine under the boom. If that's the case, you need to secure the turntable rotation by either using a house lock pin (if Grove fitted one), or extend the boom a bit and lower boom until boom tip contacts the ground, which will prevent house from rotating when gearbox is removed. If swing gearbox is located under boom, it's a different method altogether. Once turntable is secured, you start out by removing small motor on the very top of swing gearbox (not shown in pic). Once you have motor removed, you'll have some threaded holes to install lifting eyes. Yes, you're going to have to employ some form of lifting device as that gearbox is a bit weighty. At this point, remove the large head bolts (15/16" I believe) that secure the planetary gearbox to turntable base. Once these bolts are removed, lift the entire unit from machine. Now you have two choices, 1) a simple rinse, or 2) more thorough cleaning. For simple rinse, open fill plug hole, lay gearbox on its side and drain as much old oil as possible. Then add some Varsol or Naptha to fill hole, install plug, and roll unit on ground to rinse inside of gearbox. Drain solvent, repeat until it comes out clean. If you go with choice #2, that's a bit more involved.
Thanks Willie, the turntable does have a locking pin and as luck would have it is still with the machine - so I will use that and drop the boom to ground to secure against another murphy's law act. I have no choice but to split the gearbox having failed in getting the old oil out and I cant imagine it coming clean without being split. However I was wondering if I could split it in place - ie remove the hydraulic drive motor on top and having removed the twelve smaller holding bolts lift it off completely - no it wont be light - and then I could get access to the top of the gearbox??? That would allow me perhaps to get access to the top plane of the gearbox and use cleaning agents, etc to throughly clean the gearbox. Having lost a piece of nylon air line (very hard) as well as the state of the oil it just has to be done. so much for me just checking the oil level!!! I cant imagine any seals lasting any time at all with nylon cutting them up. The photo shows the larger bolts at the bottom and the smaller bolts at the top - my thought is to remove the top bolts and try to remove the top motor first p is that right??? The drive is in the side compartment - so access is OK - but lifting something??? I have an excavator with hook but could be tricky??? I will see what it looks like once the top motor is off but would be pleased for preparatory advices on what is ahead of me. Oil out through the drain hole will not do the job at hand & so maybe losing the nylon air line does not matter as it has to come apart anyway rather than taking a short cut. So tell me about choice 2 - albeit he harder choice. I will supply pictures as I go along willie, Regards, MX45. nb I would supply a picture of the oil but if you can imagine a black hole with a pungent odour you would get the picture - I think it is the worst condition of any oil I have ever had to change.
MX, if you're going to bust into the gearbox, proceed with due focus and take notes as you go, there's a good bit of goodies inside those things. And you will likely have to remove the entire unit to properly flush it inside because with swing gear box planetary units, any debris (metal wear) or fragments always drift to the bottom bearing of the unit, thanks to gravity. If you disassemble the unit with the lower housing still fitted to the machine, not likely you'll be able to properly clean out the very bottom of the unit. If you remove the house covers on that side of the machine, I don't see an issue with you disassembling unit on machine as opposed to yanking it as a whole to keep from having to deal with the weight of an assembled unit. The first thing you would do would be remove hyd motor (not show in pic). Then you'll be left with the swing brake and planetary housing still in place. The swing brake would be the housing that the hyd motor is mounted on, it should have a hyd line going to it. Once you've removed the hyd motor, disconnect the hyd pipe going to the swing brake, remove the bolts that fit the swing brake to the upper planetary bearing carrier and remove swing brake unit. Now you're down to the planetary unit. Before you disassemble that unit, you need to put some marks on the components for reassembly. Don't bother with a center punch to make marks because the planet gear ring is hardened steel and will knock the tip off a center punch. Instead, use a die grinder with a cut off wheel to grind some marks on outside of planetary housing components as noted with red lines in pic below. This will help you to orient parts when you go to reassemble. Once you get these reference marks made, remove the 1/2" bolts that fasten the bearing carrier to top of planetary housing, remove bearing carrier. At this point, this is where I'd much prefer having the planetary unit removed from the machine. By now you'll see a good bit of parts inside there, and myself, I wouldn't hesitate removing those parts, but pay close attention to the location of the various components. Yet, even if I pulled the guts from that unit with it mounted on machine, you still cannot properly clean the very bottom of the unit where all the debris has settled. I would much rather remove those bolts that mount the planetary housing to the turntable base and yank it so I could rinse the housing with solvent and flip it upside down to remove debris. Keep in mind, I'm only offering brief description of the process you're going to have to follow, you will find components that you will have to decide how to deal with them when you encounter them, hard for me to note a detailed description for disassemble and reassemble. And you will need some new o-rings to seal the parts that you have disassembled.
Thanks Willie, I am going to be saying that a lot in this coming week or two, Can I remove the hydraulic motor and brake assembly as a unit from the bearing carrier???????????? Please say yes? That would save some disassembly??? Regards, MX45
It's been a long time since I've worked on Grove units MX45, I really don't remember how those were assembled. But with most swing boxes I've worked on, when you mount the hyd motor it covers the bolts that mount the brake unit to the planetary housing bearing carrier. I think it will become obvious to you once you start disassembly as to what will be required. Be sure and take some pics as you go.
Starting - G'day Willie, Probably wont get much further this week as very full week but here attached is the start I have made. Protection Panel removed - a number of the small bolts removed but I cant get to the ones at the back as insufficient space to turn a spanner - so whole unit has to come out to be worked on. Loosened the bottom large bolts - very tight - however the last one under the half inch frame around the main hydraulic cylinder is very difficult to get to. I have had a 450mm adjustable wrench on it and with hammer cant break the bolt loose - not much room to move under the boom??? If you have some ideas they would be welcome. I have marked the units as you suggested and will probably spray a little paint as well to be certain I line everything up the way it is supposed to on the way back together. I could use a large cold chisel to move it but that will damage the bolt head???? Socket too tall to fit it and the arm??? I have sprayed it with WD 40 but I think it is simply a function of being tightened to over 120ft lbs and not been moved since it went in??? Any ideas welcome to move that bolt - it is high tensile - Regards, MX45 NB Four photos showing the troublesome nut, marks on parts, acrow prop under basket just in case, and boom overhead to which I will attach a chain and block to lift the unit up and lower down to wheelbarrow.
Yes, those bolts can be a bugger to get to. I think I would begin disassembly process with it mounted on machine. First, remove the hyd motor with crossover relief valve mounted on motor. Then remove brake from bearing carrier. At this point, you may be able to pull the bearing carrier off of the planetary gearbox housing. If you can make it that far, you may be able to slip a good size drift shaft behind planetary box, place tip of drift on top of bolt head, and give drift some good hard whacks with a sledge. Sometimes this impact helps relieve bolt tension and allow you to remove bolt with proper size box end spanner, not an adjustable spanner or open end. Remove all the bolts you can, working your way to the ones on the backside. If necessary, use a gas ax to put a little heat on the mounting ring that bolts screw into, don't have to get it red hot, just a little heat on the outside of the ring right where bolts thread into it.
G'day Willie, I put the big cold chisel to the nut which could not be got to easily and soaked it in WD 40 for a few days. I managed to take an edge off but in a way that assisted as I was then able to get a 3/8th drive 21mm socket and bar on to it by wriggling - pure luck! Of course I still could not move it - but got a very thin piece of alloy tube - must have been strengthened in some way - and put it over the end of the bar and wobbled a lot. It cracked twice getting it loose but all good now. But out of time this week so I will get back to it in a couple of weeks and let you know my progress or lack of it. I think the tension the alloy tube soaked up as I pushed on it actually assisted the breaking of the nut - seemed to store the energy to maintain the tension on the bolt. Very lucky for me - I had been looking for answers in the tool store that were economical. Be back soon, Regards, MX45
OK - after some other dilemmas got back to the drive - block and tackle over the top - disconnected the bearing carrier and the main connecting hydraulic supply and the connecting hydraulic line - that allowed me to swivel the whole unit which was necessary to get it up and out. I hve just tried to attach three photos - hope it worked. Any advice Willie now I have the bottom section removed. I did have a washer fall out as I dismantled - you can see it on top of the bottom assembly in the third photo. It either goes there or under that large planetary gear? Thanks MX45
It's been a long time since I've been into one of those units, don't recall the disassembly procedure. Pic is really bright, hard to see details, is it just the pic or does that shaft look a bit gnarly on the end? The washer you refer to is likely the thrust bearing washer, will likely be one above and below the planetary unit, possibly even a flat needle bearing thrust bearing that rides on washer. On some units, that shaft in the center which drives the sun gear will now pull out of the planetary unit, then the planetary unit will lift out of the ring gear case. If you have to pull the output shaft, there's typically a retainer bolt accessible once you pull the planetary unit. Many times that bolt is tight, might have to drop the dissassembled lower section back in place on machine so it will engage the ring gear of the turntable, put a couple of bolts back in the planetary case to secure it and put some meat to the bolt to break it loose. Be sure and take pics of components as you disassemble, might help you when you put it back together.
Thanks Willie - I have dismantled the gears and they pulled out easily. Not so easy to see the thrust washers as the oil was so dark and clingy that it made them blend in with the gearing. However it makes sense the way I have pulled it apart and set it piece on piece as it came out. All degreased and sitting in a plastic container. Gears look fine - there is a little movement in the bearings but no real noise or marks of consequence that I can see. The bottom of the main drive shaft does not have any visible marked oil leakage and there is no real evidence of significant oil leakage under the drive unit. The gear at the bottom appears to be held on by two screws but without the oil seal warranting replacement and bearing serviceable I think it is better left alone. I have to wait for two new o rings as they did not have them in stock. So no rebuilding for a week or so until they can arrive in town. Of course if that oil seal should fail it would be a complete dismantle again??? What are your thoughts??? MX45
Now that you mention it, you may be right, that bull gear on the bottom may be retained by some bolts, remove them, remove bull gear, and shaft goes out the top. With no access to diagrams, I can't verify that. Things are actually looking pretty good in there, which is a good thing. Concerning your second question, should I or shouldn't I, ahh, that's the age old question. No way to answer it, but it's one of those things, if that seal starts leaking promptly after you put it back in service, it's always discombobulating when one finds ones self kicking his arse with his own boot leather. It sure would be nice to take it all the way, and go ahead and fit a new seal in the bottom. I will warn you though, not that I can say this unit will be this way, but typically that output shaft is rather snug in the bearings, takes a good bit of persuasion to push it out or drive it back in. Keep us posted with the progress.
G'day Willie - I have time to think - there is a circlip on top of a washer over the bearing on the inside of the bearing carrier - I am guessing the circlip would allow the gear to be pressed out the bottom although possibly the two slot screw heads on the bottom of the gear that enages the ring gear might reveal another connection. My leaning is to leave it alone as the bottom of the bearing case has no evidence of an oil leak and I use the machine sparingly when running. Just got overquoted a few times to remove a few tree limbs in the figures of hundreds and then thousands of dollars. So for $8k delivered I thought the machine was worth it. I have used it many times now for jobs I would have had to contract out. Easily paid for itself and I still have the machine albeit it requires some TLC. The bottom bearing as much as I can see has no big scar marks or sense of hardening being gone from wear - but of course cant see it all. So when the o rings come in a week or so I will put it back together - with pics and troubles as I find them. Once I have got it back together with some good peace of mind about oil and not sludge I can get back to trying to adjust the pot that works on the control panel for swing - it is way out of whack giving trouble. That is another story. Hopefully I wont cause myself grief by making a damaging error on rebuild. Thanks, MX45
I got ya, and I can't see the retainer ring you speak of in the pic, but I know what you're talking about. That probably is the removal procedure, remove retainer ring, press shaft out the bottom, and "press" is required, that shaft is typically snug in the bearings. I'd dump some kerosene in the housing, rotate the shaft to rinse the bearings good, dump it out, repeat until it drains clean, then invert the unit to let kerosene drip out until dry. The reason I say this is any debris, wear filings, etc, settles to the bottom in those bearings. If you're not going to drop that shaft, at least clean out the junk in the bottom of the unit.
G'day Willie - got to take the little fella to his swimming lessons next so last contact today - I used degreaser and let it saturate the bottom bearing - washed out with garden hose - sprayed with WD40 whilst on side and did get metal filings out - turned the bearing centre shaft and sprayed again. then repeated today with WD40 again. Will probably give it a few more turns yet to be as sure as possible - WD40 has a fine plastic long nozzle so I could get inbetween the rollers. Oil that came out had like two layers when drained - one thick sludgy clingy and the other still black as night but thinner??? Sort of some elements of the oil clagged together and separated from the rest??? Cheers - MX45
Yep, you're seeing what I'm describing. All the "dregs" of use settle and wind up in that lower section, where the output shaft bearing are. WD40 is a decent solvent for that application, clean it as best you can and proceed with assembly, hopefully you'll have no worries for a couple of years.
G'day Willie, Well got some time today and made some errors. Got the whole unit back together and aligned all the marks but after a couple of hours of trying it was obvious it was not aligned??????????????????????????? So story is when you think about it the planetary gears although aligned with the ring gear and all the external marks are aligned I had naturally moved the drive gear when cleaning the old oil and debris out. So thinking, thinking, thinking! I took the top half of the drive off - the brake and hydraulic drive which allowed me then to remove the planetary gears which then allowed me to move the base unit to line up the bolt holes - not possible before - and then reseat the ring gear on the aligned marks and bolt the brake and hydraulic motor back on. But wait there is more. In doing so I noticed the ring gear was off set but thought the new o ring would press into place. Bad mistake. So with oil migrating up the sides and out from the joins took it apart again. O ring destroyed and caught on the lip and cut to pieces. so picked the best of the two old o rings - not too bad and put in much more carefully and made certain it was seated without pressure before bolt tightening - which I was getting more proficient at as the day wore on. Oil came up out of the boltholes but I am presuming I spilled oil in there and as I tightened it came up with nowhere to go. I cleaned the outside with WD40 and will check tomorrow for any new oil seepage - I hope I dont find any. Tricks - took forever to try to get the drive aligned so the gears would engage. Tolerance for the moulding of the drive unit and base is very tight. Used grease on the mating parts and meant to be slide fittings to make it easier - I think it would have been very difficult without doing this. NOt a unit designed to be worked on readily but OK I guess if you do it all the time. I will let you know in a few days how it turns out if I have a bit better luck. MX45
Yep, those are finicky little critters to work on MX45, but it's all good, even the mishaps, just more of life lessons learned which is a good thing. I do hope you get it sorted out without any more gremlins.
Well - the swing still works which is a nice positive and no strange noises - not that you would hear them. Small oil weep in bottom o ring but I will silicone the outside once cleaned and not worry about it. Should work well enough. Now to the issue that started me looking at everything here. Electrics question. I have schematics and I have the instructions for adjustments on the controls. I adjusted the other controls and had success getting them working much better. However the swing control had a relay that activated the solenoid to allow the hydraulics to work as the signal from the control box was insufficient. What I used to have was no swing left or very late engagement and sporadic. Swing Right was full swing or nothing - no speed control. After adjusting for getting left swing working as best as possible I have right swing going full and no speed control but also have no stopping on return to centre - you have to move it left to get it to stop -which it does. On left swing I have creeping swing which is late to engage and no speed control. Now here is my theory - the centre potentiometer is out - my solution is to somehow - and maybe someone knows how - to move the centre position of the rheostat/potentiometer to engage left swing earlier and right swing later and perhaps that will re-centre the pot enough to allow the rest of the electronics to do the work they are supposed to. How stand my theory Willie and does it make sense, have you done this before?? ON anything like this??? The alternative is to put a pot inbetween the relay down at the solenoid controls and inbetween the relay and the solenoid and trial and error set it at a point I am contend is slow enough not to create speed/stopping danger. I think I can re-set the other pots for adjustment to less sensitivity in order that the right swing does disengage on return to centre - is this in fact a better route than trying to adjust the pot on the control lever??? If so what sort of pot would I use??? Thanks for any feedback. New control would cost money not to be spent on a machine that serves use just for trees on my pty. Regards, MX45
Well, I'm not certain about the MZ66B, I used to work on some MZ66A machines, don't know how similar they are. The A series used OEM controllers, possibly the B series did as well. I assume boom, swing, telescope, and drive use the same type of proportional controllers, if so, I would consider putting the goofy controller on telescope, and putting the telescope controller on swing. You can tolerate a little goofy operation with telescope, but swing needs to be smooth and consistent going both directions. If it does have OEM controllers, I can't remember the proper adjustment procedure, I'm more familiar with PQ controllers that JLG uses. Do they have 3 adjustment pots? Maybe Threshold, Max, and Ramp? As for the potentiometer, yes, if I've ran across one that's slightly faulty, yet still works, I have moved them "off center" at the drive gear to keep a machine operating, sometimes it works, sometimes not. If it's a three terminal potentiometer, you should be able to test it's operation with an analog ohmmeter to determine if it's faulty or not. If necessary, maybe shoot an email to Hindley Electronics here in the US, tell them you're an Aussie that doesn't have a good local parts supplier, and that a bloke in the US recommended them, they can possibly give you some info on type of potentiometer to purchase to replace your faulty one, and possibly how to properly adjust controllers. Be sure and include the OEM numbers that are printed on the circuit card in your email. https://www.hindleyelectronics.com/
One further symptom - on the ground controls the swing does not swing left at all and the right swing does stop on switch going to off??? I have adjusted the resistance of the two main resistors to standard on the ground controls.
What do you think Willie - firstly since the left swing does not work from the ground controls and it delivers current from a different circuit as I understand it & only when the cage controls are adjusted right up does the Left Swing start to operate and then only at a slow speed - it could be that the Left Swing Solenoid is the culprit. Now I know it has had this problem since I first got it and that the previous owner put in a 12 v relay in circuit that put 12v through to the solenoid when the controller(either cage or ground) sent a signal and it works at full speed. I used to feather the switch but that can be tricky when you are close to something - prefer to feather it at a lower speed. Idea is to put a pot inbetween the relay 12v output to the solenoid and by trial and error operating the ground controls - choose a speed that is slow enough to be safe and set the pot in that position??? If I read the current ability of the relay and knowing that they handle the operating loads then I could pick a pot of the same ability and install and then just adjust the cage controller back so it does not continue right when controller is returned to centre - ie turn the adjustments back down????????????? Your thoughts please????? MX45
If I understand what you're saying, your theory is it won't swing left from ground controls using toggle switch because it's getting phantom voltage signal on other wire which cancels out solenoid operation, possibly from platform controller? It's been a long time since I've worked on a Grove, remember little about them, but if it's like the MZ66A, Grove was fond of using all white wires with leeeetle bittty numbers on them, can be a PITA to work with and follow the wires. I would typically start troubleshooting at the platform as those proportional controllers commonly fail. But in your case, I think I would start with the ground controls and get a base of proper operation before moving to the platform. If at all possible, locate the two wires (A and B terminals on upper platform controller), find where those two wires connect to lower terminal strip to operate swing, then disconnect them from terminal strip. This will remove the platform controller from the swing circuit and allow the swing valves to only be operated by lower control toggle switch. If it still doesn't work proper, we have some investigating to do at the lower base. If it does work proper, that indicates problem is either platform controls or problem with cable going down the boom.
G'day Willie - I got some local advice from the Service Agents - who cant help otherwise since they are 700kms away. I was advised to swap wires at the solenoids and see if the problem swapped sides. The problem remained no left swing and right swing worked fine off LH Swing controls. So eliminates the electrical fault idea. Down to solenoids and hydraulic circuits. I know the hydraulic block in question should be squeaky clean as I had to replace the cylinder holding the hydraulic piston as it had a fine crack in it and leaked a lot of fluid over a year. Now even though the coil is weather proof I wonder if some oil has not got in there and damaged its performance. Reason is the next recommended procedure was to remove each of the coils and swap sides and see if the problem moved. That was to eliminate the coils but moving the coils is not so easy so I chose to measure the resistance of each coil. Good coil measures 3 ohms - bad coil it seems measures almost 7 ohms. I would think that would more than cut half the available current to the movement of the hydraulic piston??? What are your thoughts and solutions Willie, et al????? Thanks MX45
Whoops - good coil measures 7 ohms and bad coil measures 3 ohms. My guess is the lesser resistance coil has a short about 3/7ths of the way up and cant create a strong enough field to move the hydrualic piston but if you connect a relay which allows full power drain then the coil produces enough magnetism to move the hydraulic piston but makes the swing go full speed. So maybe a pot inbetween the inserted relay output and the coil??? The original signal from the controllers must be regulated in some way? MX45
I'm not much use with this issue MX45 as it's been so long since I've worked on Grove machines that I don't even remember what type of proportional valves/solenoids they used. Also don't recall the ohms values of those coils, for all I know, a range from 3 to 7 ohms may be normal, just don't know. I understand what your saying by fitting a relay to coil to boost voltage and thereby make it work, the problem I have with doing that is that it's on the swing function. I would be willing to do a trick like that on, say, telescope, but not swing. The reason being, when the boom is retracted, you could possibly tolerate rapid movement of swing with little proportional control, but once you get that boom extended, the swing movement would be a wilder ride than 8 seconds on a pissed off Brahma. What I would like to do is remove the solenoid coils from the proportional valve as suggested and switch the coils. If problem is now right swing, you would know the coil is faulty. At that point, I would either replace the coil or at the very least switch it with one of the boom telescope valve coils. You can tolerate a little more radical movement with telescope than you can with swing or boom up/down.
G'day Again Willie, Took an easier step - replaced the boom extension coil with the swing left coil. ONe above the other rather than trying to get to one on the opposite side. Too hard unless absolutely necessary. BINGO - boom extension worked very slowly - swing left went back to working properly and I re-adjusted the thresh, ramp, hi, lo to safe standards for the swing - God it is so nice to not have the cage working wickedly. Thanks for your input and I have sent a thanks to the service centre who helped in the 1 2 3 's for working it out. I put the relay in place to get the extension going otherwise would wait a month for it to open. Bit of a spill of Hydraulic Oil on replacing but tightened back up and looks OK. So bit of a process but wiser operator now and machine a bit more trustworthy even if only used on private property nice to be kept safe by advices. I have asked for a coil and will see what price - maybe a cheaper option with a choke of some sort after the relay before the coil. With coil at 3ohms - no current but who knows when current runs??? Coil is first option. If they are pricey here in Australia do you have a contact in USA for coils??? Sometimes over here price is equivalent to extortion. Thanks again Willie.
Good to hear you're making progress sorting it out. :drinkup If you can determine what brand the valve is that the coil operates it's likely you can find a supplier online. I can't recall what brand proportional valve unit that Grove used.
The old 40' Grove we used to have had Sunstrand valves if im not mistaken... Getting a manual for one of those is going to be rough if you dont have one. Call All Crane here in Ohio 800-232-4100, they used to be a huge Grove dealer. i am guessing they can help and might have the parts you need.
Thanks for the feedback - I did swap the whole unit ie actuating piston/cylinder and coil so still a chance it is the piston/cylinder but not likely. I can live with full speed extension but not full speed swing. Everything is marked Parker - Ohio - 1997 - so I expect it is all Parker gear. Local service guy - well I call him local at 700kms away - asked the same thing about identity as many different systems were fitted. I will let you know how I go. MX45
G'day, No joy with the coil at this time - service agent cant identify the coil type from photos of set up and Parker numbers. I will take more and send again. Now for the interesting thing. Talking with a friend about how to drop the voltage/current from the relay output we pondered all sorts of complex controllers interceeding. But we needed more information. So plan devised was to put a 12v globe in series or parallel with the relay output to the coil ( which had it operating at full speed). Now tried a few in series and was not having any joy - too much resistance and no movement from the extension on ground controls. Then talked some more and put in series a 55w halogen light bulb (ex fog light bulb in the spares cabinet) and the ground control worked fine. Light glows when operating. So went and tried the cage controls and was very very surprised to find that they not only worked on extension but the proportional controller also worked with the light globe in series. WOW! BINGO! A 55w halogen globe provides the right resistance/voltage drop/current restriction to allow the controller to deliver its' signals to the faulty coil. So only problem I see is when the globe goes I will lose extension - but then I can contract and repair and go back to work. Hey - how about that luck of having a globe do the job with a relay - $20 solution for much more expensive problem and perfectly fine for my use on acres!!! MX45
LMAO, a literal application of the proverbial "light bulb going off in my head". Now that you've discovered a 55W halogen bulb provides a resistance that makes the coil operational, could you check the ohms resistance value of the bulb with an ohm meter then obtain a ceramic resistor of that value to take the place of the bulb?
I had not thought of that but I have another bulb exactly the same and can measure it and mabye figure it out - but the bulbs' resistance will increase when under power??? Thinking leave well enough alone or as we say here in Oz - if it aint broke dont fix it!!! On another matter Willie - I just hooked up my old backhoe attachment - Dirt King - to the 753 Bobcat - worked well 7 or so year ago when I put it there and meanwhile I bought the Excavator which is safer - but when hooked up nothing works - I mean nothing - I have the quick connects on properly - I have the continous flow light on. There are no movements at all - like something is blocked - or should I have it on something other than continous flow - but that is what I remember. If I am not doing anything wrong what is the most likely cause for me to look for. Already had gremlins today when the bobcat failed entirely. Checked battery and failed under load test - only 6 mths old - but then on taking it out and testing under load it worked?????? Turns out corrosion on the wires connnected to the terminal and the terminal cracked so you think you have pressure with the tightening of the nut but you dont. So new terminal and cut new end to +ve supply wire and OK now - but then the Backhoe???????? So I have downed tools for today and turned to the forums for some guidance. Just getting it out to take some photos of it working and put it on E bay - just because it aint being used. Feel free to edit and relocate my new problem here - I am not sure which forum to put it in - bobcat/backhoe??? Regards, MX45
No worries MX45, start a new thread in skidsteers about your Bobcat problem, thread title it something like "Bobcat 753 backhoe attachment not working", this will catch the eye of the Bobcat guys at HEF. Voodoomojo and Bobcatdan are pretty sharp on Bobcat machines, but not likely they'll spot your question at a thread about a Grove aerial lift.