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  • Rod Bearing Replacement

    Let's see if I can post this with out getting bashed about searching past post. (which I have done).
    I have a 60 Hawk with a 289, automatic trans, that has developed a knock.[xx(] It does not knock when cold, has great oil pressure but when it warms up the oil pressure drops to a point that it scares me around 10-15 at 2000 rpm. A long time friend tells me it is most likely a rod bearing.
    So out comes the shop manual, I believe this can be done in the car. I am going to pull each plug wire while it is running to narrow down the search. I will replace both bearings on the journal that has the bad rod bearing.
    Now for my questions, what is the best way to replace the rear seal?
    Does any one have a gasket list? or any advise on this process[?]
    I am going to buy all the parts at York this year.
    I have done a couple of brand X newer motor rebuilds but nothing this old. I have no knowledge of the engines prior life other than it has sat for 20 years prior to me flushing the engine, changing the oil after every run of 30 min. The knock is bad when giving the gas or letting off, Does it sound like a rod bearing to you guys?

    I want to keep the stude motor even though my uncles have a ton of old chXXy motors they are pushing me to put in the old girl.
    ANY help or thoughts would be Appreciated.

    Thanks Rodney Tucker


    Rodney
    60 Black Hawk
    On the road Again

  • #2
    Sure sounds like a rod bearing. You'll most likely have to buy a complete set of bearings, so instead of wasting time to find the bad one, I'd change all of them because the others probably need it. Before you order them, you might want to drop the pan and check to make sure of their size, standard or undersize. Sure wouldn't want to put in new bearings that are too loose to start with.

    I've changed several Stude crank seals, but not while in the car. Will have to leave that one to the more experienced guys out there.

    Comment


    • #3
      Before you buy any parts, I'd drop the pan and see what you are dealing with. If the knock is bad, it's likely that the crank is damaged. You'll want to measure or plastigauge the rod and main journals on the crank.

      IIRC, you can get Stude bearings in .001 and .002 oversizes. If the crank isn't damaged and is still standard, might be what your measurements would tell you to buy.


      Dick Steinkamp
      Bellingham, WA
      Dick Steinkamp
      Bellingham, WA

      Comment


      • #4
        I agree with Dick's ideas here. Kinda silly to diagnose an engine, or at least, buy parts for it's fix unless you've looked inside it OR you're planning a complete overhaul.
        If it were mine, I'd be tempted to replace ALL the rod (and possibly main) bearings if I were gonna go to the trouble of doing one. BUT - if you're planning on going to York, I'd bet you COULD buy just ONE rod's worth if that's what you wanted.
        The one time I was there, I recall a guy showing up and selling parts out of the back of a pickup truck, amongst which were a whole BUNCH of NOS rod bearings at giveaway prices! In retrospect, I wish I'd taken the whole mess off his hands!

        Miscreant adrift in
        the BerStuda Triangle


        1957 Transtar 1/2ton
        1960 Larkvertible V8
        1958 Provincial wagon
        1953 Commander coupe

        No deceptive flags to prove I'm patriotic - no biblical BS to impress - just ME and Studebakers - as it should be.

        Comment


        • #5
          ...and furthermore,

          If it is one rod knocking, you probably won't fix your low oil pressure problem by replacing one rod's bearings. If one is THAT loose, the others are probably loose enough that replacing only one rod's bearings will probably not help your low oil pressure situation.

          Low oil pressure could also be cam bearings or perhaps the oil pressure relieve valve is stuck open? Oil return passages blocked in the heads not allowing drain back and low oil pan oil level?

          The knock could be loose flywheel/flex plate bolts, cracked flex plate?






          Dick Steinkamp
          Bellingham, WA
          Dick Steinkamp
          Bellingham, WA

          Comment


          • #6
            Thanks for the input.
            Dick I never thought about the flywheel. I am going to go home and yank the pressure relief valve out, check it over. I flushed the engine from top down with a solvent and boy did the gunk fly out. But I did it until it ran clean, flushed it again with oil, Left the engine open for 3 days to let her dry out. Strikes me as odd that cold it has 40 psi at idle then it drops to nothing.

            Again thanks for the input and keep it coming, as I have read before on this site, the book does not have stuff that 40 years of experince working on these jewels does. Again Thanks

            Rodney
            60 Black Hawk
            On the road Again

            Comment


            • #7
              I guess flushing and flushing seems like the thing to do when you pull a valve cover and find accumulated "gunk" built up. Myself, I wouldn't do that. The engine's survived all these years like that and at worst, this gunk was maybe a handicap of a pound or two of extra weight.
              Along with itself, the gunk COULD HAVE been holding fast onto any debris that might have found it's way into the engine. To think that some spraying and draining got EVERY bit of gunk and debris to march right out the drain plug is only fooling yourself. Will the engine run any better for your flushing? No.
              Perhaps the knock was there before you started this "clean-out" but if you did the clean-out in hopes it would cure the knock, it was not a good strategy.
              A freshly rebuilt engine - using today's improved oils - shouldn't build up deposits of gunk like the old, non-detergent oils caused.

              You can pull the relief valve if you want. Since the engine was all gunky before, I can guarantee you it won't be easy to extract the actual plunger of the valve. The bore is tight and the built-up varnish in the area where the spring resides will inhibit the plunger from coming out. While I've heard of stuck relief valves, I've never encountered one except on a bare block that had set for a number of years and the plunger had rusted to the bore.
              Usually, since this valve works immersed in flowing oil all the time, it's one of the least likely parts to gum up.
              Whatever you do, don't stretch the spring to see if you can "bump up" oil pressure![:I]

              Miscreant adrift in
              the BerStuda Triangle


              1957 Transtar 1/2ton
              1960 Larkvertible V8
              1958 Provincial wagon
              1953 Commander coupe

              No deceptive flags to prove I'm patriotic - no biblical BS to impress - just ME and Studebakers - as it should be.

              Comment


              • #8
                Before you tear into it, put in some really heavy weight oil, like straight 50wt racing oil. Note any differences in the time it takes to begin knocking and how much oil pressure it holds. Back in the bad old days, I replaced one rod bearing, went to 40wt oil and drove 'er another couple of years.

                Hoping not to scare you, experience says you are most likely to find worn cam bearings and rocker arms as well. When the engine is cold, there is sufficient oil pressure to hold the worn rod away from the crank. As all the moving parts and the oil warm, the clearances get larger and the oil gets thinner. Oil starts escaping around the cam bearings instead of being held in the crankshaft.

                It is to be hoped you have a random rod bearing failure, but that is not common with Studebaker V8s. Replacing the rod bearings may buy a few more seasons of driving, but you might start budgeting for a complete rebuild.

                thnx, jv.



                PackardV8
                PackardV8

                Comment


                • #9
                  sigpic
                  Ross.
                  Riverside, Ca.
                  1957 Provincial X2
                  1958 Transtar

                  Comment


                  • #10
                    Often times, a clue to it being a rod bearing is to rev the engine a bit and close the throttle. Many times a rod bearing will bang louder immediately after you close the throttle. Take heart in knowing the forged Stude crank may not be damaged. A while back there was some discussion about cast iron cranks being stronger than forged cranks. One of my old combines has a Chrysler slant 6 with a forged crank. A number of years ago I was shelling corn and had to get off the machine for something. That's when I heard over all the other noise (and through my ear plugs) the kind of rod knock that immediately gives you that sinking feeling in the pit of your stomach. I don't know how long I'd run it like that. I shut it down, cussed a few times and walked to the house to lick my wounds. The next morning I fired it up and got it to the shop as quickly as possible with that thing banging to beat the band the entire way. I pulled it apart and that one rod bearing was beat completely down into the steel and even that was very deeply scored. I figured it was going to be crank grinding time but I looked it over, miked it and it was fine. Not skinned up a bit. Nothing. Cast cranks may be stronger but that told me right there that forged cranks are much tougher. New bearings and rings and it's run fine ever since. My brother knocked out a rod bearing in his tractor that looked almost exactly like my bearing. His tractor had a cast crank and it measured up to .090" under, way to bad to be ground. Rather than weld up the crank and turn it down, he just swapped engines.

                    Comment


                    • #11
                      After reading Dicks post and others, I did pull the relief valve and it was stuck about half way. It was a pill to get out but 3 adult beverages later and a few choice words out she came gummy and black. Cleaned it up per Manual, Changed oil, went with straight 50w as Ross hinted to an BAM 60 psi cold at idle, Warm Idle 25 psi. I only let her idle for so long.
                      The rod bearing or whatever it may be does not make a peep when at idle. I did pull each plug wire while listening to each cylinder with a doctors scope and it is very strong around Cyl 6.
                      Since the car has never seen the road only garage and drive way. I feel like the crank will be fine I am going to do all rod bearings and mains while I have the pan off as well as the front and rear seals, She does leak a little oil. Heres a pic



                      Ok Well I tried # times and cant the pic over

                      Rodney
                      60 Black Hawk
                      On the road Again

                      Comment


                      • #12
                        You are right on John it is louder getting on and off the throttle, not to bad at a steady run.

                        Rodney
                        60 Black Hawk
                        On the road Again

                        Comment


                        • #14
                          quote:Originally posted by abndad

                          Here is the Link to the pics
                          Pretty Hawk []



                          Certainly worth some time to get that motor sorted out.




                          Dick Steinkamp
                          Bellingham, WA
                          Dick Steinkamp
                          Bellingham, WA

                          Comment


                          • #15
                            First off....If something has excessive clearance putting thicker oil or several cans of STP in the engine will do nothing except prolong the situation and probally let you down later when you need the car.

                            2nd, if you put new bearings to your old crank without having it ground undersize by a machine shop, DO NOT assumme .002 or .005 under bearings will give you an okay clearance. Use plastigauge and put strips of aluminum foil behind the bearing shell as needed to give a good clearance. If this is done right it will last fine.

                            Kent




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