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Source for pressure gauge

Discussion in 'Fisher Engineering Discussion' started by aveguy, Jan 31, 2013.

  1. aveguy

    aveguy Junior Member
    from VT
    Messages: 13

    Doing some debug on my plow. Can you folks recommend a source for getting a pressure gauge kit together? I am thinking 3000 or 5000 psi gauge and typical set of fittings required to tie into Fisher MM1 Insta-Act system. I would like to aquire as cheap and quickly as possible. I see gauges on ebay, but I would have to add an unknown set of fittings. Was hoping there might be a kit available. Fisher list kit 56686 but I can't find a source or listing for whats included. Thanks
     
  2. kimber750

    kimber750 PlowSite Veteran
    Messages: 3,638

    Any local hydraulic shop should have the parts you need.
     
  3. dieselss

    dieselss PlowSite Fanatic
    Messages: 10,958

    Sometimes ace or other box stores. If not might have to order online
     
  4. RepoMan207

    RepoMan207 PlowSite Fanatic
    from Maine
    Messages: 5,031

    Depending on how much you want to spend. I have the fisher one, it comes with ALL the fittings, guides, and hose. The only thing that is extra is the XLS / XV adapter.

    Short of that, Grainger has the gauges themselves. You'll just need to piece together the fittings, and hose.

    Fisher part # : 56686 & the XLS / XV adapter 6-4F50X Parker. I paid $45 for the kit, and $8 for the XLS / XV adapter.

    [​IMG]
     
    Last edited: Feb 1, 2013
  5. aveguy

    aveguy Junior Member
    from VT
    Messages: 13

    Thanks repoman for the picture of the fisher kit. If I had been able to locate one of those locally I would have just bought it, since it was simple and complete. It took me a while to find a local hydraulic shop that could set me up and it cost a little more. But I now have a gauge, fittings, hose, etc. In the long run the extra cost was worth it ... bacause the guy that sold me the stuff is very nice & knowledgable about all sorts of hydraulics including fisher . And he is also willing to help/advise me if needed.
     
  6. aveguy

    aveguy Junior Member
    from VT
    Messages: 13

    Ok, here is my follow up post which explains why I was looking for a pressure gauge.

    (In case you don't want to read the long story below, I will tell you up front that I had an inner o-ring seal leak on the pump pressure relief valve. The solution was to remove and clean the valve and replace both inner&outer o-ring. Than adj pressure using a gauge.)


    While reading please keep in mind that I have zero experience with plows and hydraulics. But I do have decent mechanical and electrical skills and tools. Just nothing specific to plows.

    Description of equipment:
    Plow is a ~2002 MM1 straight 8ft with early Insta-Act. I bought it 2nd hand in ~2007 from a dealer and had them mount it on my 2002 1500HD chevy sliverado crew cab. Up to now the plow hasn't had any issues. Which explains why I don't have any experience with plows, cause I haven't had to fix much of anything. I am only plowing my own drive way and I don't beat on it. I changed the filter once and the oil twice since 2007. Which I realize isn't often enough, but like everyone else.... life gets in the way.

    Statement of problem:
    Midway through the last snow event, I noticed the lift rate was slowing down. And by the end of the job it was having a hard time lifting the blade. Left and right seemed fine. The next day I when I started my investigation it was lifting better than the night before. However it still seemed a little slow. ie took 4-5sec to lift rather than 2-3sec. In other words everything was working, but just seemed like the performance was off a little. Honestly if I hadn't noticed the more significant degradation the night before, I might not have given it a second thought. But the cumulative clues left me with an uneasy feeling that there was a problem lurking.

    Known issues prior to the event:
    Here are some issues and concerns that I knew existed and needed to be addressed. I was hoping that correcting these issues would fix the problem or at least eliminate them as the source of the problem.
    1) Small leak in gland nut seal on lift cylinder. The leak has been there for a while but the night of the incident I thought there was more oil leaking than normal. The cylinder was rebuilt back in 2007 just days after I purchased the plows because it had a leak issue. I suspect the original owner or shop swapped/updated the lift cylinder because it is a gland nut style where as my left/right rams are the older packing nut style.

    2) Small leak around the base of electric motor. It's had a suspect pump shaft seal leak since I got the plow. A few years back I purchased the tool and seal but never got around to changing it. So I figured it was time to do it.

    3) Changed the filter and oil back in 2007 when I first got the unit. And changed oil only again in 2010. Not the best record given it should be done every year. So for sure it was time to do it again.

    The work sequence:
    1a) Talk to everyone who will listen and explain the problem. That includes the lunch table guys and the wife. Note to self, the guys at work are more interested than the wife.

    1) Checked reservoir fluid level, and to my surprise found it wasn't down very much. Which means my lift cylinder and shaft seal leak couldn't have been all that bad. But went ahead and disassembled cylinder and replaced gland nut with the newer single unit/blue seal $20. I was hoping that the leak might have reduced pressure and/or possible air issues. At this point I only changed the gland nut/seal and retested. The performance was still off.

    2) Now I think maybe the electrical system, electric motor or pump are weak. So before I did anything else, I measured the voltage & current at the motor under load. Voltage was a little lower than I expected at 10.5-11.0V @ 155amp DC under full relief load. The no load voltage was ~14.5v which indicated that truck was charging. I wasn't sure if the >3v drop at motor under load was normal or not. But it put me on notice to clean all terminals and a possible weak motor relay. The good news is that the motor was turning and wasn't shorted since the 155amps was under the 190A max spec. Keep digging.

    3) Time to drain all the fluids, replace inlet filter and the shaft seal. While removing the electric motor I realize that shaft seal leak has allowed some hydraulic fluid to push into the motor. Also the motor internals are very dirty, full of carbon dust due to the fact that the brushes are 75% worn. Hum... maybe the motor is weak? Take it to local DC motor shop who says they will test and inspect for $10. Good news, they clean, test and replace brushes for $55. Motor is good to go which will help eliminate any concerns it being the problem. Also the brass bearing race on the valve body for the motor shaft looks good. After rebuild the motor draws 170A which is up from 155A. I assume the increase is due to improved/cleaned contacting in communtator, brushes, etc.

    4) Some sludge in base of reservoir, minor dirt on the existing inlet filter. Not enough to cause the issue at hand. But enough to reinforce the fact that I need to clean and change oil more often. Shaft seal replacement goes well, I had the Fisher tools which makes the job a lot easier and ensures a quality repair. Since I had to remove the hydraulic pump to replace the shaft seal, I opened it up to clean & inspect. More good new, the pump looks good. No visible signs of wear at least to my untrained eye.

    5) Now at this point I asking myself if I should pull all check valves, relief valves, cylonoids and values to clean and replace all o-rings. I decide not to. I was convinced that all the other work was going to fix it. I also did not want to risk breaking something. In hind sight I wish I had taking it all apart. But I was thinking/hoping the problem was a weak motor and/or old fluid.

    6) Put it all back together and test. Slightly better, but the performance still seems off. Time to buy a pressure gauge.

    7) Purchased a gauge and inserted it into the lift cylinder circuit. Measures 1400psi which is below the 1750psi spec. Also noted that the pressure build slow and the rate of build slows even more as pressure builds. Now at least I can see the problem. Note to self... diagnostic test equipment is ALWAYS required regardless of what wife thinks.

    8) Attempt to adjust pump pressure by turning relief valve. Pressure is adjustable, but can't achieve much more that 1500psi. Also pressure still builds in a weak non-linear manner. In the back of my mind, I am now thinking hydraulic pump must be weak/worn, regardless of what I thought when I inspected it. No experience here so not sure what to make of this. Getting late so knock off for the night. Start digging into Fisher docs I downloaded the other day. Train myself to read hydraulic schematics and symbols. It comes easy due to my extensive knowledge of electrical/electronics, everything has an analogous function.

    9) From this study I decide there could be a leak-by issues in one of the valve seals. Now I find myself wishing I had pulled everything and replaced all o-rings. I decide to start with the pump relief valve. I remove and clean the valve/seat/ball/spring and replace both inner&outer o-rings. I suspect a worn inner o-ring seal leak since I can just barely see some signs of wear on the o-ring. Reinstall and adj pressure using a gauge and retest. Pressure build faster and in a more linear manner. Pressure adjustments are more responsive and I am easily able achieve 1750psi on the gauge at the spec default screw turns. PROBLEM FIXED! :)

    10) Run in the house and annouce that the plow is fixed... wife still not interested :(

    p.s. I have a bunch of pictures if anyone is interested.
     
  7. kimber750

    kimber750 PlowSite Veteran
    Messages: 3,638

    Congrats on fixing it yourself. Thumbs Up
     
  8. Tony350

    Tony350 Senior Member
    Messages: 546

    If it makes you feel any better about the wife not being interested at least we are. Glad you got it fixed. I would like to add a pressure gauge to the toolbox as well. I didn't even know fischer made them.
     
  9. aveguy

    aveguy Junior Member
    from VT
    Messages: 13

    Pictures of the plow and repair are at the link below. The pcitures where never taken to serve as a tutoral, but rather as an aid to ensure that I could put it back together. In some respect the pictures are not really any better than the exploded views in the Fisher docs. However some of the pictures of the pump internals and elec motor maybe of interest if you haven't seen one before. My new gauge is also shown.

    http://s952.beta.photobucket.com/user/mar_myphotos/library/auto/Plow

    p.s. I am starting to get a lot of rust. Time to start thinking about repainting it this summer. Are there any good threads on the best practice for repainting? Do folks save/replace the decals?
     
  10. BBC co

    BBC co PlowSite.com Addict
    Messages: 1,883

    how long of a process start to finish would some one guess this takes if replacing all o rings etc
     
  11. aveguy

    aveguy Junior Member
    from VT
    Messages: 13

    Are you talking experienced(Shop) or inexperienced(DIY)? Per my prior post you will note that I was inexperienced. I had a lot of wasted time figuring out what was wrong and what to do next. I also did not replace all o-rings.

    But if I had to estimate how long it would take me to do it again...
    1) 30min drain, disconnect and remove electric motor & valve body from truck.
    2) 45min to remove reservoir,pump and replace shaft seal & inlet filter.
    3) 1hr to strip out all valves/solenoids and replace o-rings.
    (I didn't do all, so just guessing based on the ones I did do. Some orings are small and hard to handle. Would be nice to have a tool to push them on/over the valves. Anyone know of such a tool?)
    4) 30 to reinstall unit on truck, fill with oil and pressure adj.

    So lets say 3 hrs. to be on the low side, so I would plan on at least half a day or more. In addition there maybe other complications which I might be unaware of, given that I did not do full 100% tear down. For example I do not know if it is possible to set the left/right cross over relief pressure(4000psi) using a gauge or if it's set only using screw turns. Pump relief pressure(1750psi) is easy to set with a gauge, but for dynamic cross over I assume you would have to trigger the cross over relief valves with external pressure to blade left/right and monitor the gauge pressure. Not sure how to do that yet or even if the pro's do it. But I would suggest prior to removing the relief valves, your count the number of CW turns to bottom out. Compare your turns to Fisher recommended initial settings. If they are reasonably close than after reinstalling just reset them back to original turns from bottom. That at least should get you in the ball park, than put gauge on it.

    Fisher sells a complete set of o-rings in what they call "Backup O-ring Kits" which I think was around $20. All the o-rings are commingled in a single bag. Took me 0.5hr just to sort and bag them by size. It's worth the time to pre-sort them.
     
    Last edited: Feb 10, 2013
  12. BBC co

    BBC co PlowSite.com Addict
    Messages: 1,883

    Wow Thanks for the fast, detailed response!
    I'm on the DIY side first plow, bought it used self installed etc been a learning curve as you know. So I really appreciate and thank you for taking the time to msg me. I think I have narrowed my current issue down to water in the hydro oil, check the fill nut and it's brown and thin but has oil texture and feel.

    Was wondering also If I was just to replace the filter and completely change all the oil in the system could you DIY those steps for me? Because my current idea was to just drain the reservoir and refill cycle a few actions redrain etc. but that is due to being clueless as to how to even change the filter nvm the rest.

    also I have a break issue if your really good with general truck diagnostics, details are in this thread last few pages if your bored want to do a little light reading b4 bed ;) http://www.plowsite.com/showthread.php?t=136987&page=147

    Either way regardless of any further input I appreciate the help! Thanks!

    :mechanic:
     
    Last edited: Feb 10, 2013
  13. aveguy

    aveguy Junior Member
    from VT
    Messages: 13

    I don't know which plow you have but the inlet filter kit for mine is 66763-1. Most of the Fisher kits ship with installation instructions. You should be able to get the pdf for that kit off the fisher website. If not let me know and I will scan a copy. The instructions do a good job of explaining the steps. After you read we can talk and I can add a few pointers. Lot of good docs on fisher site and well worth spending some time to figure out which ones are for your plow.

    With regard to flushing... don't do it they way you outlined. You want to manually flush the rams to get all the old oil out. Here again the last page of that instruction sheet tells you how. In a nut shell get the blade off the ground just enough so it will turn left/right 100% w/o hitting the ground. You can short chain it or put a 4x4 block under center or jack or what ever, just make sure it's safe once it's up. Than make sure the lift cyclinder is 100% down once off ground. Disconnect the hoses at the pump and drain the lines into a bucket. The lift line wont have much because when down most was pushed back into tank. But there will still be some fluid in it's hose and very base of lift cyclinder which will drain out. The majority of the fluid will be removed from the r/l rams when you hand push the blade left and right after. This way all the old fluid is removed from all the lines and rams. The cylinders/pump are self bleeding for air via the vent port on valve manifold body, so no worry there. Make sure you have the hose secured into a bucket, because when you hand shift the plow blade it's going to squirt out hard.

    If the plow is new to you(how old?) I would recommend removing the resovior base after draining in order to clean it out. Than at that point you can inspect/replace the inlet filter. The plastic filter stem can be a little hard to insert into base of pump. But it will go and we can review more when you get ready. Replace with real plow fluid(blue stuff) rather than ATF, others may feel differently but I think it's the best stuff for the job. It takes about 2.5Qts but I always get a gal($20-$24).
     
  14. aveguy

    aveguy Junior Member
    from VT
    Messages: 13

    I went to the link you posted to read about the brakes. But all I saw was one comment that said you lost them and it was at the shop. Not enough detail to draw any conclusions. Are they going to the floor and no stopping power? Or are you getting a grinding noise? Is it at the shop, what are they saying? Looks like a newer truck, what year? I was expecting a rust bucket and was going to suggest a broken line. But not at that age.
     
  15. BBC co

    BBC co PlowSite.com Addict
    Messages: 1,883

    Thanks, was a pin hole in a rear brake line so back to the plow.

    I got the Filter Kit 66763-1 read thru it. Plow appears to be early 2000's it's an LD they no longer sell them that may narrow it's age down a bit. has the Instact pump. I purchased it in 1/2011. Looked to have been sitting awhile was low on fluid, filled it then and never been low since. [​IMG]

    [​IMG]
    So I was looking at the drain in the reservoir and if I am removing the reservoir to replace the filter, would it be possible to just do that then chance any issue with the drain plug arising looks a little rusty and may need heat to break it loose but not sure. Any idea what the cost of a new reservoir would be?

    And to remove the reservoir the diagram is showing 4 - 3/8" or 5/16" screws holding it to the manifold,, to replace the filter these are the only ones that need to be removed?
     
    Last edited: Feb 13, 2013
  16. aveguy

    aveguy Junior Member
    from VT
    Messages: 13

    Hi BBC co,
    1) Correct, there are only the 4 small bolts holding the reservoir to the base of manifold. Please keep in mind that the manifold is AL so mind your torque, or you run the risk of stripping stuff. There is a large o-ring around the manifold and the opening to the reservoir canister which will create some resistance while sliding the reservoir on/off the manifold interface. Make sure you lube all oring with hydraulic fluid before installing. I noticed that your plow appears slightly different than mine. It looks like you have a black steel frame member sitting directly below the reservoir canister. That may make it difficult or even impossible to remove the reservoir without first moving the manifold up. It's hard to tell from the picture if there is or isn't enough room for reservoir to clear the frame while pulling the canister down for removal. Maybe someone with more experience can chime in.

    2) I have no idea what a new reservoir would cost. Have you already attempted to remove the drain plug and know it to be frozen? For handling simplicity, I would attempt to carefully and gently remove the drain plug while it is still attached to the manifold. I suspect it will come out easy given that the internal threads are probably good(rust free) due the presence of reservoir oil. The majority of what you can see as rust is associated with the nut that is welded to the base of the reservoir canister. The drain plug itself is a treaded shaft with Allen head center that reseeds into the canister base nut. In other words the drain plug itself is pretty well protected and should come out easy. If it doesn't come out, than I suppose you could dump it out the fill plug before removing it from the manifold. I imaging it would also be possible to remove the reservoir from the manifold while full of fluid. But that method is likely going to result in a mess. Long term I think you need a functioning drain plug, hard to imagine having to live without it. Getting the fluid out prior to any eventual manifold removal is also going to reduce the weight of the assembly.

    3) I do still think it is worth the effort to remove and clean the reservoir. And also replace the inlet filter. Otherwise you have no idea what things look like in there and that kind of defeats the purpose of changing the fluid. If there is a black return filter you will also want to clean that. The kit doesn't come with a new return filter, but I suspect you could order one. Just make sure the 66763-1 filter kit fits your plow before buying. I gave you that number as a starting point for looking over installation instructions.

    4) Is that rust or hardened dried grease on the lift ram chrome shaft? Neither of which is helping the gland shaft seal. If possible and w/o damaging the shaft finish you might want to clean that off. After you finish plowing and while controller is still in float mode (blade down, power on) push that ram down by hand to get it protected from the weather. I was told the gland nut will leak a slight amount of hydraulic fluid and helps to keep the shaft clean. I was also told that during long term storage(summer etc) to spray the exposed shaft lengths with WD-40 to help prevent rust. Maybe others with more experience can comment, is WD-40 a good product for this use?
     
    Last edited: Feb 14, 2013
  17. BBC co

    BBC co PlowSite.com Addict
    Messages: 1,883

    ok probably gonna get to it today, have not attempted any thing past looking at it. the kit was given to me buy a parts dealer based on my pictures. I also bought a new lift ram.
    What does the return filter look like it's not the oval one in the kit?
    I was told whit lithium grease for the rams but am open the the wd40.
    I heard wd40 does not interact well with orings in the past not sure about on the rams myself.
     
    Last edited: Feb 14, 2013
  18. aveguy

    aveguy Junior Member
    from VT
    Messages: 13

    BBC co,
    One more thing I just remembered. in order to change the inlet filter itself, you will also have to remove one of the five bolts holding in the hydraulic pump per the instructions. That 1 bolt hold a steel support bracket for the plastic inlet filter tube. I suspect the bracket is just an additional safety to prevent the inlet filter from accidentally working it's way free. The filter tube seems to hold it's self in pretty well, so the bracket must just be for backup. Make sure you study and take pictures of the existing filter orientation before removing. Per the instructions there are several different orientations based on different pumps. You will want to compare your existing arrangement to the instructions and ensure that you know which is the correct orientation. If the existing and the instructions don't line up than you will want to resolve that.
     
  19. aveguy

    aveguy Junior Member
    from VT
    Messages: 13

    Retrun filter is black, round and is much smaller than the oval inlet filter. It's installed near the inlet filter. Not all units have one. You can easily remove the old one(spring clip), inspect the screen and clean. To clean mine I just blow some low pressure air through from both sides. Don't use a lot of air pressure, the screen is soft. I never really found mine all that dirty. Go look at my pictures on photobucket from an earlier post.

    In addition to the very large reservoir oring, there are two small o-rings in the kit, One goes on the inlet tube. The other is the pump outlet o-ring. Since you will not be removing the hydraulic pump from the manifold you will NOT need the pump outlet oring. After all you are only removing 1 of 5 of the pump bolts. Just make sure you get the correct sized one for the inlet tube and don't mix it up with the pump outlet oring. From what I have been able to tell there is NO oring between the oval filter and the plastic tub which you will have to snap together. The oring is only used at the end of the tube that pushes into the base of the pump. I warn you... it pushes into the pump hard. You may have to tap it in with a small hammer and drift stick. Just make sure it goes in straight and that the oring looks good as it passes across the interface. Once in you can turn the tube but even that might require some leverage.

    ya I would like to know more about WD-40 cause it was a dealer that told me to use it. It very well might not be the right stuff for the job.
     
    Last edited: Feb 14, 2013
  20. BBC co

    BBC co PlowSite.com Addict
    Messages: 1,883

    10-4 will do. thanks for the tip on the possible need to remove that bolt