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CUCV question - what is this thing?

Discussion in '1982-Present GM Diesel' started by Mastiff, Feb 1, 2005.

  1. Mastiff

    Mastiff 1/2 ton status Premium Member

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    I was poking around under the hood of my new-to-me CUCV last night... There's a silver box looking thing on the firewall a little to the passenger side. It has two spring/wire clamps holding the cover on and some hoses coming in and out. One of the hoses goes noplace, just hangs down, like it's just for purging/venting or something (unless it's hooked up wrong). Can someone tell me what this thing is?

    If nobody can tell what I'm talking about I'll snap a pic and draw a circle around the thing.

    Another Q while I'm typing. Does the 6.2L diesel use just any old oil like a gas engine would use? I noticed the filler said only to use this or that types of oil. The type designations meant nothing to me.

    Thanks.
     
  2. BlueBlazer

    BlueBlazer 1/2 ton status

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    1) Fuel filter.

    2) You need diesel rated oil. CH or CI rating preferred. Rotella T, Delo 400, Mobil Delvac are all good oils.
     
  3. Mastiff

    Mastiff 1/2 ton status Premium Member

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    Thanks. I considered fuel filter, but I could swear I could trace the fuel line from up the frame rail to the mechanical pump to the top of the motor, very much like a gas SBC. I'll look closer in the daylight... :grin:

    By the way, what's the difference with diesel rated oil? Does it run hotter or cooler or something?

     
  4. joez

    joez 1/2 ton status

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    It handles the soot a lot better than a conventional S rated oil.
     
  5. Mastiff

    Mastiff 1/2 ton status Premium Member

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    Gotcha. Now, that fuel filter, you need to purge air from the fuel system if you replace it? I'm assuming it's a replacement deal as opposed to cleaning. Sheesh, I guess I ought to get some manuals instead of relying on you guys...
     
  6. Mastiff

    Mastiff 1/2 ton status Premium Member

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    Nevermind my last question, I read the sticky post about changing the lifter pump and it cleared everything up.
     
  7. kennyw

    kennyw N9PHW Premium Member

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    Most diesel rated oils you will find will come in 15W40. Rotella T is my preference but there are many good ones out there. Even Walmart sells a generic 15W40.
     
  8. rivermtnman

    rivermtnman 1/2 ton status

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    LOL Mastiff, I think that was my first question when I looked under mine, "What tha heck is that shiny thing???". I've already replaced mine.

    You may want to check Ebay, I bought a military manual for these trucks, I think $8 shipped, thats on cd-rom, probably as detailed as any Haynes manual. I like it because I can search for specific words and find things quick.
     
  9. rivermtnman

    rivermtnman 1/2 ton status

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    Back to the oil question, I thought I saw somewhere?? that it recommended 10-40 under 40 degrees and straight 30 for over 40 degrees. I'm not sure I'm stating this correctly, but is what I thought I saw. 40 degrees is bad temp when its 50/30 around here. Do most of y'all just stay with the same weight year round? I also did not know there is diesel specific oil.
     
  10. joez

    joez 1/2 ton status

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    I run 15w-40 Rotella year round. When this case runs out i think im just gonna go buy a barrel of it.
     
  11. BlueBlazer

    BlueBlazer 1/2 ton status

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    15W40 if there is a chance it will get over 40, if it will be continuously under 40, I run 10W30 Rotella. Where I live, 10W30 is only run for about 3 months or one oil change so it works out nicely.
     

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