Gear Oil Change

kordokordo Member Posts: 243 ✭✭
Like most of you, I have been changing my gear oil with the little hand pumps that are very slow and hard to use.  It occurred to me this morning that there is something about this process that doesn't make sense to me.  What if I drained the drive and put the lower plug back in and filled the drive from the the expansion/safety bottle at the top of the engine until it started dripping out of the top plug on the drive?  Then I could put the top plug on the drive back in and fill the expansion/safety bottle to the required level.  This would be much easier than using that little hand pump.  I know there is something wrong with my logic since this is not the standard procedure but I don't know what it is.  Anyone have an answer?  Thanks.  

Comments

  • Dream_InnDream_Inn Member, Moderator Posts: 7,671 mod
    If you do not pump it from the bottom up, you will get air in the drive.

    Dream 'Inn III -- 2008 400 Express

  • kordokordo Member Posts: 243 ✭✭
    edited August 2020
    I can see that.  The tolerances are very tight in the drives and the oil has a higher viscosity than normal so an air bubble might develop and stay there much longer than for a regular transmission.  I'm going to have to think about getting a pump, the plunger system is a pain in the a$$.  Thanks for input. 
    Post edited by raybo3 on
  • Black_DiamondBlack_Diamond Member Posts: 5,439 ✭✭✭✭✭
    Going to be difficult to find a pump to handle 90w oil and does low flow too. Needs to be a fixed displacement type, like a gear type if you want it powered. That plunger pump is probably the best option. lol

    Past owner of a 2003 342FV
    PC BYC, Holland, MI
  • aero3113aero3113 Member Posts: 9,071 ✭✭✭✭✭
    Find a motor and rig it to pump the hand pump. Set everything up turn it on and walk away, let the motor do the pumping.
    2008 330EC
  • aero3113aero3113 Member Posts: 9,071 ✭✭✭✭✭
    If you can heat the 90 Wt. oil before you use an electric pump, it should help.
    2008 330EC
  • PickleRickPickleRick Member Posts: 4,038 ✭✭✭✭✭
    edited August 2020
    If the electric pump is adequate for gas/oil/diesel you'll have no issue. 

    Id just make sure you have a pump that is @5psi. You don't want stupid high pressure.  

    I've used regular automotive electric fuel pumps over the years to pump old gas, diesel, gear oil, old engine oil and hydro fluid.  I've used efi 45 plus psi pumps and carb specific 5 to 6 psi pumps.  Just make sure whatever you use is self priming.

    The only difference I found was the carb pump was slow!!!


    Like others have said, warm it up.  On a 70 degree day you shouldnt have an issue of needing to warm anything. On a 30 degree day, you might have flow issues.

    90wt oil isn't much thicker than diesel.  90wt is close to about 40wt and diesel close to about 10/30w 

  • PickleRickPickleRick Member Posts: 4,038 ✭✭✭✭✭
    edited August 2020
    Ive never used a pressure pot pump to add oil but I've used pneumatic pumps for extracting oil, gas, etc.

    They were amazing.  Sadly they didn't last very long once all the fuel started containing ethanol..
    I quit buying them as they stopped working after a year and they are not cheap.  

    That's when we went to the electric pumps.  We. Hook up the pump and by the time we are done pulling plugs, filters, etc shes drained. 

    Having the right tools makes a job much easier.

    When you have hundreds of items waiting for a service, just 30 seconds per repair adds up.  


  • PickleRickPickleRick Member Posts: 4,038 ✭✭✭✭✭
    We used to sell our waste oil but since the price of crude oil dropped so much they quit buying it and started charging to pick it up.

    About 2 years ago we built a rocket stove. We burn pallets and all or old gas/waste oil for heat now.  

    Now we dont separate gas from oil.  I find a 50/50 oil to has drip burns and flows best 

    Do you use an oil burning furnace?
  • PickleRickPickleRick Member Posts: 4,038 ✭✭✭✭✭
    Sounds about like the mixtures we run.  If we dump it, we burn it. 

    Every now and again I'll have the drip a little too fast and she'll smoke like a diesel tractor pull.  

    We'll have a customer come in and ask if the shop is on fire.  
Sign In or Register to comment.