Page 1 of 2 12 LastLast
Results 1 to 10 of 13
  1. #1
    Bronze Member Amez's Avatar
    Join Date
    Oct 2005
    Posts
    50
    Location
    BC,Canada
    Tractor
    Jinma 284

    Default head bolt retorque

    Does anyone know if a 50 hour headbolt retorque is required on a 2007 Jinma or do they have multi layer steel gaskets (or torque to yield headbolts)? The manual says nothing about it.

  2. #2
    New Member
    Join Date
    Apr 2006
    Posts
    18
    Location
    ky

    Default Re: head bolt retorque

    Hello ! I would check the head gasket that came in your parts kit. The one on the tractor and the one in the kit should have come from the same bunch.This was is not 100% sure but a good start. Good luck ! joe

  3. #3
    Elite Member RonMar's Avatar
    Join Date
    May 2005
    Posts
    2,742
    Location
    Port Angeles WA
    Tractor
    Jinma 284 delivered 06/28/05

    Default Re: head bolt retorque

    Regardless of the gasket material, I don't think confirming/re-torqueing will hurt anything. Then you at least know the status of the head bolts/studs... When I did mine, I found and removed quite a bit of machineing debris in the head when I removed the rocker assembly to accomplish the retorque.
    Ron

  4. #4
    Bronze Member
    Join Date
    Aug 2007
    Posts
    83
    Location
    Whitehorse Yukon Canada
    Tractor
    JM254 4x4

    Default Re: head bolt retorque

    Yes,

    And yes, Hope the attachement works. It took me abbout and hour to complete. I did mine at 73hrs. Set clicker torque wrench to 105ft/lbs. Nothing budged. So at least it was torqued properly at the factory.

    YukonKing





    JMretorque
    Attached Files Attached Files
    2007 JM254 with FEL and BH

  5. #5
    Super Member greg_g's Avatar
    Join Date
    Dec 2003
    Posts
    6,028
    Location
    Western Kentucky
    Tractor
    JD3720 Cab, 300X loader with 4-in-1 bucket

    Default Re: head bolt retorque

    Quote Originally Posted by YukonKing
    Set clicker torque wrench to 105ft/lbs. Nothing budged. So at least it was torqued properly at the factory.
    Not necessarily true. What if one or more of them was torqued to something in excess of the factory spec? Or maybe undertorqued - but rusted in place? Without loosening them before resetting torque, you'll never know.

    I know Mike Stuart's document says it's not necessary to loosen first - I simply have a different opinion.

    //greg//
    USN (Ret)
    Former Chinese tractor owner (x4)
    Current John Deere owner

  6. #6
    Veteran Member Bob Rooks's Avatar
    Join Date
    Feb 2007
    Posts
    2,244
    Location
    Bothell & Silverdale, WA
    Tractor
    Yuchai Bulldozer

    Default Re: head bolt retorque

    Quote Originally Posted by greg_g
    Not necessarily true. What if one or more of them was torqued to something in excess of the factory spec? Or maybe undertorqued - but rusted in place? Without loosening them before resetting torque, you'll never know.
    I know Mike Stuart's document says it's not necessary to loosen first - I simply have a different opinion.
    //greg//
    I'm on Greg's side. You'll never know what you had unless you undo it. This is what Caterpillar used to recommend.
    In some cases it is impressed upon to see what the "break-loose" torque is/was, wherein you use a dial torque wrench set to zero then take the "break-loose" value for reference. Although this practice is reserved for multi-million dollar engines where you must have a BS just to change filters, it won't hurt a thing.
    Yuchai YCT dozer, Mustang 2040 skid steer, Mitsubishi MS035 Mini-Ex, Trimble equipped 7' Dual Dozer, and a LiTW BH7600 back hoe for sale.

  7. #7
    Bronze Member
    Join Date
    Aug 2007
    Posts
    83
    Location
    Whitehorse Yukon Canada
    Tractor
    JM254 4x4

    Default Re: head bolt retorque

    Mmmm,

    Fair enough, but the recommendation is to not loosen. Even though they may have been over torqued at least it wasn't leaking up till now. (aint broke don't fix it). But I would think you are risking things moving. In my opinion if your breaking them loose you should be replacing the gasket. Plus when they were initially torque beeing brand new, assembled with lots of oil, now after many heating and cooling cycles with the oil drying out a bit they could actually require more torque to break them than when they were put in? An extreme example is any old hardware on most vehicle, say 10 years old... it usually takes more to break them than when they were new? I realize that 50hours bathed in oil is not the extreme but maybe? Anyhow i'm sure either way I will get many more hours out of my little Y385 diesel.....I hope.

    So what is the correct way...........? Heck if I know.

    YukonKing

    Either way I am very impressed with these Engines/Tractors up till now.
    2007 JM254 with FEL and BH

  8. #8
    Advertiser
    Join Date
    Mar 2005
    Posts
    584
    Location
    SE VA. NC State Line
    Tractor
    Jinma Dealer / Importer. General Tractor Repair Shop.

    Default Re: head bolt retorque

    Hey YukonKing,
    I am not on Greg's side but, I recommend breaking the head bolts loose for a retorque and have done so for many years. It has been a general practice in my field. I would never oil the threads unless you have a wet thread spec.


    As of yet these engines do not have torque to yeild head bolts.

    Ronald
    Ranch Hand Supply

  9. #9
    Bronze Member
    Join Date
    Aug 2007
    Posts
    83
    Location
    Whitehorse Yukon Canada
    Tractor
    JM254 4x4

    Default Re: head bolt retorque

    hey,

    no worries, the more opinions, ideas and information the better. the only reason I offer my opinion is because I bought a tractor. if i haden't I wouldn't be on here.

    but the question remains should he retorque? I think yes.

    P.S. Its spring here I have 8 inches of mud around the house i'm building and living in.

    peace
    2007 JM254 with FEL and BH

  10. #10
    Veteran Member Bob Rooks's Avatar
    Join Date
    Feb 2007
    Posts
    2,244
    Location
    Bothell & Silverdale, WA
    Tractor
    Yuchai Bulldozer

    Default Re: head bolt retorque

    If you want to do it the correct way, remove each bolt one at a time (in sequence), clean and oil the threads (most torque values assume clean oiled threads and head seat) and then re-torque to 2/3 of the final value. When you have completed that, then torque to the final value (in sequence).
    It seems kinda anal retentive for these engines, but you asked.


    Head torque trivia
    On the RND Sulzer engines, the "head studs (about 4-1/2" dia.)" go all the way down through the crank bearing caps (approx 22 feet); the nuts are spun on hand tight and then "pinged" with a slugging wrench. All that while under 12 tons of hydraulic jack tension. Six at once.

    Fuel injection trivia:
    The RND is a two-stroke diesel engine. Every time the injector "pops", there goes ~85 gallons of HFO.

    Enough; back to tractors.
    Yuchai YCT dozer, Mustang 2040 skid steer, Mitsubishi MS035 Mini-Ex, Trimble equipped 7' Dual Dozer, and a LiTW BH7600 back hoe for sale.

Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
© 2014 TractorByNet.com. TractorByNet is a registered trademark of IMC Digital Universe, Inc. Other trademarks on this page are the property of their respective owners.