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  • Engine: Oil pressure (again)

    I bought an Avanti that came with a parts car. That Avanti had been in a fire or on fire but it was just the back half and interior that was burned. The engine was to have been rebuilt and when I remove the head and wiped the piston top clean the .030 ink stamp was still visable. I took the motor apart cleaned and checked what had been done. The only changes I made was to replace the cam, lifters, cam and crankshaft gears. They had wear patterns on them that I didn't like. Cam bearings were new, crank turned, new bearing etc. All the clearances checked with plastic gage and when reassembled turned over by hand smoothly. The engine sat 3 years until I now have a car to use it in. Engine sounds good but has low oil pressure 30lbs top 5 or less at idle. Verified pressure with another gage. I checked the plug in the distributor tower. It's there and I pumped oil using an electric drill and no leakage in that area. I had the valve covers off while looking for leaks and no oil leaking from the rockar arms. Removed and replace oil pressure relief valve although all looked good. With the engine running on 3 occasions I watched the gage suddenly go up to 65 lbs and then drop back to 25-30 lbs it was. There was no change in engine speed the oil pressure just went up and then back down. This was the first Stude engine I've taken apart (never had to before) and someone had it apart before me so the problem maybe something I overlooked or something that was left out that I missed. I'm going to take the front of the engine off and pump some oil with the drill and look for leaks and them drop the pan and look at the oil pump. Any other suggestions of things to check or do?

    Ken

  • #2
    It sounds like you have a bearing clearance problem or maybe a severely worn oil pump causing your low oil pressure. Are you sure that the oil pressure relief valve isn't sticking in the open positiion? Bud

    Comment


    • #3
      This could be a problem in the Full Flow Oil Filter itself, or especially the Valves in it's mounting base, or badly fitted new Cam Bearings.
      It is a good idea to always use a Wix or (WIX) NAPA Gold #1049 Filter, not Fram.

      Comment


      • #4
        Lets be accurate...

        The correct number is a Luber-finer p/n# PF24
        The spec's are:
        Spec.ValueO.D.:3.77 [96mm]Height:4.21 [107mm]I.D.:13/16"-16 UNS Thd.PSI Relief:NoneAnti-Drain:YesBuyers Guide ApplicationAmerican Motors (1975-85), GM Products (1967-80) (GM 6437462, GM 6437462, 6437994)



        If NAPA, it would be a p/n# 51258
        Part Number:51258UPC Number:765809512580Principal Application:AMC (60-81), GM (67-80)</B>All ApplicationsStyle:Spin-On Lube FilterService:LubeType:Full FlowMedia:PaperHeight:4.338Outer Diameter Top:3.660 Outer Diameter Bottom:Closed Thread Size:13/16-16By-Pass Valve Setting-PSI:NoneAnti-Drain Back Valve:YesBeta Ratio:2/20=11/30Burst Pressure-PSI:345Max Flow Rate:9-11 GPMNominal Micron Rating:21
        Gasket DiametersNumberO.D.I.D.Thk.15314 2.834 2.462 0.200


        In Fram, it would be a p/n# PH25
        Part Number PH25
        ZoomPH25_12808.jpg
        Anti-Drain ValveYESGasket I.D.2.42"Gasket O.D.2.8"Gasket Thickness.2"Gasket UsageBaseProduct Height4.05"Product I.D.13/16-16 Th'dProduct O.D.3.78"Relief Valve Setting PSINONEStyle Code1


        The NAPA Gold number 1049 crosses to a Luber-finer PH24 or a Fram PH11

        Part Number PH11
        ZoomPH11_12808.jpg
        Anti-Drain ValveYESGasket I.D.2.42"Gasket O.D.2.8"Gasket Thickness.2"Gasket UsageBaseProduct Height5.14"Product I.D.13/16-16 Th'dProduct O.D.3.81"Relief Valve Setting PSINONE


        Originally posted by (S) View Post
        This could be a problem in the Full Flow Oil Filter itself, or especially the Valves in it's mounting base, or badly fitted new Cam Bearings.
        It is a good idea to always use a Wix or (WIX) NAPA Gold #1049 Filter, not Fram.
        HTIH (Hope The Info Helps)

        Jeff


        Get your facts first, and then you can distort them as much as you please. Mark Twain



        Note: SDC# 070190 (and earlier...)

        Comment


        • #5
          Let's be real careful about spewing filter preferences.
          There are some pretty smart filter idjits here.
          And besides, Fram is in the process of being sold, and their prospective new owners are pretty good people.


          Originally posted by (S) View Post
          This could be a problem in the Full Flow Oil Filter itself, or especially the Valves in it's mounting base, or badly fitted new Cam Bearings.
          It is a good idea to always use a Wix or (WIX) NAPA Gold #1049 Filter, not Fram.
          HTIH (Hope The Info Helps)

          Jeff


          Get your facts first, and then you can distort them as much as you please. Mark Twain



          Note: SDC# 070190 (and earlier...)

          Comment


          • #6
            Originally posted by DEEPNHOCK View Post
            And besides, Fram is in the process of being sold, and their prospective new owners are pretty good people.

            Comment


            • #7
              What should the pressure be for an Avanti at idle?
              63 Avanti R1 2788
              1914 Stutz Bearcat
              (George Barris replica)

              Washington State

              Comment


              • #8
                Originally posted by jd-stude View Post
                With the engine running on 3 occasions I watched the gage suddenly go up to 65 lbs and then drop back to 25-30 lbs. There was no change in engine speed the oil pressure just went up and then back down.

                Ken
                This is a very puzzling phenomenon to me. Since I have never had a Stude engine with full flow, I have no clue of any mechanism that could cause this. If you have some restriction starving oil pressure and flow upstream of where you are measuring oil pressure, hopefully you have not stressed the engine enough to cause any damage. That spike in pressure is really strange on a warmed up engine.
                John Clary
                Greer, SC

                SDC member since 1975

                Comment


                • #9
                  What should the pressure be for an Avanti at idle?

                  Not sure about Avanti's but the standard V8 wants 40 lbs at 40 mph in high gear. That's from the shop manual.

                  My 232 lives with 35 at 40 and maybe 5 at idle. My Full flow 289 runs 55 at 55 and 10 at idle.

                  Comment


                  • #10
                    Thanks for your thoughts. I have a NAPA filter, looked at the oil filter base and the valves are in place and looked good. Oil pressure relief valve was clean and removed easily but swapped it and the spring for one out of another engine with proper oil pressure. Cam bearings were new but I didn't check installation. Regound cam went in easily and rotated without binding. Also no issues with reground lifters was noticed. I trust my underhood oil gage as it matched the dash gages low pressure reading and I bled any air out of the plastic line in case that was an issue. I'm favoring an oil passage plug that was removed during it's rebuild and not replaced or notice by me or an oil pump that looked good but isn't. The engine has only been garage run and I've monitored the oil pressure. It's never been high but I never let it go to nothing either. I was watching the oil pressure gage when the engine was running at a steady speed and it climbed up to 65 lbs from its 25 lbs and then drop back. That brought a glimmer of hope as it can get pressure but for some reason it isn't. Determination is replacing dissappointment and when the weather warms I will have an answer if not a fix.

                    Ken

                    Comment


                    • #11
                      Ken, one more thing...recently we had a thread about a newly rebuilt engine with low oil pressure. On that engine, an oil gallery plug that can be seen with the distributor out was left out. There was a discussion on how to check that and some of our innovative members had a solution for installing the plug through the distributor hole. Hopefully, someone with a better memory than mine will chime in and direct you to this discussion thread.
                      John Clary
                      Greer, SC

                      SDC member since 1975

                      Comment


                      • #12
                        Two things to add to your list...
                        Rod side clearance, and crank end play.

                        Originally posted by jd-stude View Post
                        Thanks for your thoughts. I have a NAPA filter, looked at the oil filter base and the valves are in place and looked good. Oil pressure relief valve was clean and removed easily but swapped it and the spring for one out of another engine with proper oil pressure. Cam bearings were new but I didn't check installation. Regound cam went in easily and rotated without binding. Also no issues with reground lifters was noticed. I trust my underhood oil gage as it matched the dash gages low pressure reading and I bled any air out of the plastic line in case that was an issue. I'm favoring an oil passage plug that was removed during it's rebuild and not replaced or notice by me or an oil pump that looked good but isn't. The engine has only been garage run and I've monitored the oil pressure. It's never been high but I never let it go to nothing either. I was watching the oil pressure gage when the engine was running at a steady speed and it climbed up to 65 lbs from its 25 lbs and then drop back. That brought a glimmer of hope as it can get pressure but for some reason it isn't. Determination is replacing dissappointment and when the weather warms I will have an answer if not a fix.

                        Ken
                        HTIH (Hope The Info Helps)

                        Jeff


                        Get your facts first, and then you can distort them as much as you please. Mark Twain



                        Note: SDC# 070190 (and earlier...)

                        Comment


                        • #13
                          I have used both Fram and NAPA 1049. I've never had a problem with either one. I do like the textured surface on the end of the Fram though.
                          I just finished all my oil service last month with NAPA filters. After paying the invoice for the NAPA, I think I will have to rethink going back to the Fram filters. I'm sure the new owner of Fram will improve their performance and image; hopefully keeping the price range they are in now.

                          Comment


                          • #14
                            I was at NAPA yesterday, and they quoted me $ 9.99 for a filter. I told them that I would wait untill it was on sale. Does anyone know when that will be? Or if you hear it is on sale, please post.
                            CASO to the end!!!!

                            Comment


                            • #15
                              FWIW, NAPA filters are the same as Wix, both made by Dana Corporation. If you find a Wix filter on sale somewhere, you're getting the same thing as a NAPA filter.

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