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  • Exhaust valve stuck open

    I am helping my friend Doug Hadley with his '54 Commander Starliner. Car just came out of paint and I am putting all the pieces back together. The car had not been run for a long time, battery was shot. Got tired of pushing it around so got a new battery. It fired up OK, but was running very rough and had a loud valve clatter. I pulled the valve covers off and discovered that the exhaust valve on #6 cylinder is stuck open about 1/4 inch. I also noticed that the top end around the valves and rockers was pretty dry, just a little bit of oil. This certainly could be a contributor to the valve sticking. Oil pressure is good on the gauge inside.

    Any suggestions on how to free up the valve, short of pulling the head off? Also what can I check on the oil delivery to the top end of the motor?

    I am a reasonably proficient engine mechanic, but have no experience with Studebaker V8s.

    All help and suggestions are appreciated.

    Pat
    Pat Dilling
    Olivehurst, CA
    Custom '53 Starlight aka STU COOL


    LS1 Engine Swap Journal: http://www.hotrodders.com/forum/jour...ournalid=33611

  • #2
    Hi, Pat,

    Prolly not seriously/permanently stuck. Last one I had like this yielded to a shot of PB Blaster and a tap with a brass hammer. The mechanic who taught me to work on Studebaker V8s was old school, but folks had been bringing him their Studes for forty years. He wouldn't even pull the rocker cover for a stuck valve until the engine had reached full hot for five minutes. "The SOB stuck itself, let it unstick itself."

    thnx, jv.

    PackardV8
    PackardV8

    Comment


    • #3
      What JV said...but one thing to be aware of is that since it was started before you were sure the valves were free, it MAY have bent some push rods when started. While you have the valve covers and rocker shafts off, you might want to make sure ALL valves are free and that no push rods are bent.

      Was this the first time the engine was started after being rebuilt?








      Dick Steinkamp
      Bellingham, WA

      Comment


      • #4
        Thanks guys. No, this is not the first time it was started. Not sure of the mileage on it, but it is fairly fresh, tops of the heads look very clean. It was running smoothly when purchased several years ago. It has been run very little over the last 18-24 months, at least. Any suggestions on the apparent lack of oil getting up to the valve train? The oil on the dipstick looks clean. How does the Studebaker V8 oil the valve train? Is this something that may clear up after warm up and running for a while? Maybe change the oil and put something thinner in there with some Rislone of similar product?

        I will check the push rods.

        Pat
        Pat Dilling
        Olivehurst, CA
        Custom '53 Starlight aka STU COOL


        LS1 Engine Swap Journal: http://www.hotrodders.com/forum/jour...ournalid=33611

        Comment


        • #5
          Add to what is noted above, also check that rocker arm carefully...it could be cracked.

          A valve stuck that bad....I'd say need professionable help to be fixed "correctly". Damage to the stem or guide can come back to haunt you. Also as Dick says, it could be bent.

          Just my opinion!

          Mike

          Comment


          • #6
            Agree with Dick and Mike, it is very possible to bend a push rod. However, the Studebaker cam lift is so low, and the pushrods are so long, there is a lot of flex in there. Since you need to pull the rockers to get a straight tap on the valve stem with a brass hammer, roll the pushrods on a flat surface to verify concentricity. Stude valve springs are so low pressure, it doesn't take much crap/crud to hold a valve open. Once the crud is dissolved, they ususally stay free as long as the engine is run occasionally.

            One other note, the Stude engine oils the valve train up and around the front end head bolt on the of the driver's side and the rear head bolt of the passenger's side. From the shop manual, "It is essential that the bottom of the rocker arm be on the oil groove side of the shaft and that the adjusting screw end of the rocker arm be on the same side of the shaft as the cylinderhead cap screw groove in the shaft, otherwise proper lubriation will not be achieved." check it while you have the rocker shaft off. Could have been assembled incorrectly.

            thnx, jv.

            thnx, jv.

            PackardV8
            PackardV8

            Comment


            • #7
              Progress report. Still stuck. Pulled the rocker arms, glad I read the shop manual first to know to drain the coolant. Good news is the rocker arms are installed correctly. Applied some PB Blast as suggested. Not sure how effective it is because there are new appearing umbrella valve seals on the valve stem, so not sure how well the penetrant can get down the stem. Let it sit for an hour or so then went after it with the hammer. I don't have a brass hammer so used a hard plastic faced hammer. I whacked it pregressively harder with no apparent results, unless it pushed the valve even further down. I layed a straight edge across the adjacent valve tips and measured how much below them the stuck one is. My measurement is hardly precise, but best I can tell it is down about 13/32. That seems like a lot. I can't find the cam specs or rocker arm ratio so can't figure out how much the cam should be pushing it open. How much piston to valve clearance is there on these motors? Anyway, my hopeful expectations have become discouraged.

              Thanks again for the help.

              Pat
              Pat Dilling
              Olivehurst, CA
              Custom '53 Starlight aka STU COOL


              LS1 Engine Swap Journal: http://www.hotrodders.com/forum/jour...ournalid=33611

              Comment


              • #8
                hi all , had this same problem on my 53 232 V8, buy a good pair of vice grips , clamp them onto the outside top of the stuck valve spring, rotate the lot around, back and forth while spraying plenty of lube into the top of the valve area, mine popped back up after several turns, give it a go before pulling the head, regards from roger

                R.A.Jennings
                R.A.Jennings

                Comment


                • #9
                  Roger, did you remove the valve spring to do this? Or were you grabbing the spring retainer with the vice grips? Thanks

                  Pat
                  Pat Dilling
                  Olivehurst, CA
                  Custom '53 Starlight aka STU COOL


                  LS1 Engine Swap Journal: http://www.hotrodders.com/forum/jour...ournalid=33611

                  Comment


                  • #10
                    hi ,sorry for the time delay , leave the spring on and clamp onto the outside of the spring at the top of the valve , this is the retainer area, rotate the whole assembley around many times, it can be very stiff so put some pressure onto it. you may have to give it a few goes to get some movement, hope this of some help, roger

                    R.A.Jennings
                    R.A.Jennings

                    Comment


                    • #11
                      There are many ways to to unstick a valve. I freed up an intake valve in a 289 that had been sitting for about 20 years. I pulled all the spark plugs so the engine would turn over by hand easily. I turned the engine over by hand until that valve was supposed to be closed on compression stroke. I backed the piston down in the cylinder a little ways. I fed a piece of 1/4" nylon rope into the cylinder. (Clean with no debris) This would allow me to carefully turn the engine by hand to push the valve up using the piston. Back the piston off a little, spray penetrating oil around the valve and tap it down with a soft metal punch. (brass, copper, alumn) Then carfully rock the valve back up with the piston by turning the crank shaft. If the spring isn't compressing the valve to low already, you could compress the spring by hand , remove the retainers, & seal to allow for better oil penetration. DON'T BACK OFF THE PISTON ENOUGH TO ALLOW THE VALVE TO FALL INTO THE CYLINDER. Work it back & forth taping the valve down & pushing the valve up with the piston until its free moving.

                      Gordon

                      Comment


                      • #12
                        Thanks Gordon, gonna try the rope trick today. Wish me luck.

                        Pat
                        Pat Dilling
                        Olivehurst, CA
                        Custom '53 Starlight aka STU COOL


                        LS1 Engine Swap Journal: http://www.hotrodders.com/forum/jour...ournalid=33611

                        Comment


                        • #13
                          Well guys, the rope trick got the valve to move up some, but it's still not loose. Still stuck about 3/16 open. It's hard to get the rope to align under the valve and not also act as a piston stop elsewhere. I am afraid it is time to pull the head and find out the whole story.

                          thanks again for your help and insight.

                          Pat
                          Pat Dilling
                          Olivehurst, CA
                          Custom '53 Starlight aka STU COOL


                          LS1 Engine Swap Journal: http://www.hotrodders.com/forum/jour...ournalid=33611

                          Comment


                          • #14
                            I had a stuck exhaust valve on my 289 after It had sat for several months. Got it free
                            by spraying PB Blaster and then prying on the spring coils by inseting a big,
                            wide blade screwdriver between lowest coils and turning/prying. The valve eventually came up but I had to repeat engine turn over several times until it did not stick. Then added
                            Rislone to keep it free. I did have to remove the rocker stack nad the valley cover
                            because the rod had come out of the lifter. Been over a year and the valve has not stuck again.
                            Hope this works for you!
                            ...Dick

                            1950 Champion Starlight
                            1963 Hawk GT
                            Santa Barbara
                            CA

                            The 1950 Champion Starlight
                            Santa Barbara
                            CA

                            Comment


                            • #15
                              Hey Pat,
                              Sorry the rope trick didn't work for you. Maybe spray it again and let it soak some more. Sometimes twisting on the retainer with channel locks or vice grips helps to turn the valve in the guide.

                              Gordon

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