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Auto Crain issues. Kenworth t300

Discussion in 'Trucks' started by chris allen, Nov 14, 2021.

  1. chris allen

    chris allen Senior Member

    Joined:
    Feb 11, 2014
    Messages:
    353
    Occupation:
    Feild tech
    Location:
    georgia
    Hey guys, I’m a field tech an put a truck together few yrs ago an been working outta it ever since, well the truck is a 1999 t300 kw, it originally had a derick digger body on it an it belonged to the power company, (use to sit lite poles). Well I removed the digger body an installed a stahl service body with a 6006h auto crain on it, well I left the big 2 stage hyd pump that was on the truck that ran the digger body, truck was equipped with big winch’s on front an rear of truck so I left the pump in place an ran the pressure line from off the lower side of the pump to my crain , well it works but tends to overheat my hyd oil an makes all the crain functions go supper slow or not work at all due to low psi when oils hot, Been dealing with this for few yrs , the pump on the truck I think has a high side of I think bout 20-30 gal a min for the winch’s an the other half of pump I think is around 13 gal a min. An my crain has to have a 8-9 gal a min supply, I’m sure feeding more gal a min will be an issue but when I use to have my service body on my old service truck an ran the original hyd pump that came with the auto crain it had been running hot aswell then too. Not sure what my issues are an can’t really get much help outta our local shop that builds service trucks, They been telling me that there behind an can’t get to me, I personally think that they just don’t wanta fool with me, I’d like to take the truck up there an leave it for them to go threw it an get the bugs out but I really can’t take the truck up there an leave it for wks at a time. It’s my only service truck an can’t really go with out it.
     
  2. Junkyard

    Junkyard Senior Member

    Joined:
    Jun 5, 2016
    Messages:
    3,291
    Occupation:
    Field Mechanic
    Location:
    Claremore, OK
    If it’s getting hot running a crane I’m gonna say you have a relief valve issue or a valve of some sort bypassing. I can’t see crane use heating up oil that bad. When the pump is kicked in and you’re not actually running the crane do you hear oil circulating through a valve like there’s a restriction? Get an infrared thermometer and take some temps to find the hotspot, that might help find the issue.
     
  3. chris allen

    chris allen Senior Member

    Joined:
    Feb 11, 2014
    Messages:
    353
    Occupation:
    Feild tech
    Location:
    georgia
    Yea when pto is turned on I can hear the pump loading up some , I’ve just had my pump off 2 wks ago for repairs, my pump didn’t have rear supports to help hold it up other than the pto drive mounts, so pump worked loose and sheared off pump shaft, so while pump shaft was being replaced I had them to change out the cartridge in the pump to the correct 9 gallon a min , think before I was pushing 12 gallons a min, so now that my pumps reinstalled to truck an rear hangers made to help hold the tail of it I’m now trying to get the few lil bugs outta my Crain. Basically when I got laid off 12 yrs ago I basically had put me a service truck together an kinda been dealing with the heat issues ever since, But my system uses a proportional amplifier electrical box that ties into a hyd proportional manifold valve (basically it’s a valve body with a relief valve an it has a electrical spool valve that’s energized for oil flow. I pretty much ran a hot wire from my remote control to the coil to turn oil on to work Crain, My local auto Crain dealer told me that with the proportional amplifier box hooked in rite would cause my heat issues, Ive asked them several times to schedule me into there shop to fix my issues an do a inspection. Needless to say they keep telling me there backed up, I personally think they just don’t wanta fool with my truck an get the lil bugs out, Just getting tired of the same ole song here an there about call them back in few months.
     
  4. terex herder

    terex herder Senior Member

    Joined:
    Nov 10, 2017
    Messages:
    965
    Location:
    Kansas
    Sounds like you could be running a gear pump against a closed center valve. Could also be the pump is shot and internal leakage is making all the heat.
     
  5. grandpa

    grandpa Senior Member

    Joined:
    Oct 15, 2009
    Messages:
    1,929
    Location:
    northern minnesota
    Too small of a case drain line can cause your issue as well.