Honda GXV390 rod and head torque values

Discussion in 'Mechanic and Repair' started by landcruiser, Apr 28, 2006.

  1. landcruiser

    landcruiser LawnSite Member
    from Tx
    Posts: 134

    I've rebuilding a Honda GXV390 (13hp, vert crankshaft) and need to know the rod torque and head torque values. Does anyone have a book on these engines that you could look this up in? Also curious as to the rod to crank pin clearance. Thanks for any help.
     
  2. Restrorob

    Restrorob LawnSite Fanatic
    Posts: 11,022

    You got your PM.....
     
  3. landcruiser

    landcruiser LawnSite Member
    from Tx
    Posts: 134

    Hey Restorob, I didn't get a PM from you. I don't know what happened but can you post the message here instead? Thanks for your help, it is very appreciated.
     
  4. Restrorob

    Restrorob LawnSite Fanatic
    Posts: 11,022

    OK, Specs. as follows;


    Rod torque, 8.7-11.5 Ft-lb
    Head torque, 23.1-27.5 Ft-lb
    Rod to crank pin clearance, Oil clearance is 0.0016-0.0026 " with service limit of 0.005", Crankpin standard is 1.4167" with a service limit of 1.415"
    Nominal bore, Standard is 3.228" with a service limit of 3.235".

    Good luck
     
  5. landcruiser

    landcruiser LawnSite Member
    from Tx
    Posts: 134

    Thanks restorob. Are you positive on that nominal bore value? This mower was bought new by the fellow I'm working on it for and has never been into. Upon dissassembly, I measured the bore at 3.465-3.466 from best to worst in the cylinder. The piston seems very tight in the cylinder as well. I hope the numbers you gave me are for a different engine - maybe a GXV340 has this smaller bore?
     
  6. Restrorob

    Restrorob LawnSite Fanatic
    Posts: 11,022

    Yeah, I did give you 340 specs. , Because the 340 and 390 use the same with the exception of the bore which I forgot about. Somebody walked off with my 390 manual. I spent a hour and a half this morning down-loading web based files that stated 390 service manual only to find the freekin things were owners manuals so I gave up....
     
  7. newz7151

    newz7151 LawnSite Silver Member
    from Tejas
    Posts: 2,419

    Well, seems our copy of the service manuals expired without anybody sending us an update disk, so I'll just have to type instead of posting a PDF capture.

    Bore & Stroke is 3.46 x 2.52 "
     
  8. landcruiser

    landcruiser LawnSite Member
    from Tx
    Posts: 134

    Sorry for you spending all that time just for me. I truly appreciate it. I bet my bore value is dead on since it only varies .001" over the entire cylinder. I have a 3 stone hone that I am honing it with but I am deathly scared of doing it too much. The stone have a spring tension adjustment and I have the spring tension as light as it will go as to not ream the cylinder out. All I want to do is put a good cross hatch in it for the rings to "bite". I've seen this done before at the machine shop so I did it the same: Put a light coat of transmission fluid in the cylinder for lubrication then run the hone up and down gently while twisting it with a conventional drill. Question is, how much? I did it a couple of times for about 30-45 seconds, then cleaned it out with a cloth. The cross hatch still doesn't look smooth and consistent and I measured the cylinder and can't tell that I changed the bore at all. I guess I need to hone it more, I just don't want to "bore" the cylinder any with the hone. Any comments or suggestions?
     
  9. landcruiser

    landcruiser LawnSite Member
    from Tx
    Posts: 134

    Thanks newz7151. My bore is dead on then. Will you read my last comments on honing the cylinder and make comments/suggestions? Thanks so much for your help.
     
  10. Restrorob

    Restrorob LawnSite Fanatic
    Posts: 11,022

    Honda cylinders are some of the hardest I've seen so I don't believe you will get into in too quickly. I use what they call a dingle berry hone, Have sizes to fit nearly any cylinder and doesn't take but a couple ups and downs to get the perfect cross hatch. Also I do mine in my parts washer with mineral spirits and a air drill,You may find using WD-40 may get you a quicker hatch.
     

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