Announcement

Collapse
No announcement yet.

to PCV or Not

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Engine: to PCV or Not

    Rebuilt 170ci. Rings haven't seated yet. Live with the blow by from tube until they do or go PCV now? Open or closed system?

    Paul
    1949 2r5 28196
    170ci 6cyl
    4spd

  • #2
    Originally posted by Old Radio Tech View Post
    Rebuilt 170ci. Rings haven't seated yet. Live with the blow by from tube until they do or go PCV now? Open or closed system?

    Paul

    How many miles on the ring job? Done right, they should seat in the first hundred miles or so.

    A closed pcv system which reduces crankcase pressure below atmospheric wil reduce oil burning.

    Comment


    • #3
      How many miles on the ring job? Done right, they should seat in the first hundred miles or so.
      Agree, unless chrome rings were installed by someone who didn't know the required bore hone finish. Then, they may never seat.

      jack vines
      PackardV8

      Comment


      • #4
        Bored .06 over. New E286F .06 over piston set (measured 3.0573). Hastings 472 .06 ring set. Cylinders were honed but I don't know what hone was used. 200 miles since rebuild. Old timer who did the work said they were chrome rings and it may take 1000 miles to seat the rings.
        1949 2r5 28196
        170ci 6cyl
        4spd

        Comment


        • #5
          I say they haven't seated because on a cold start I get oil smoke from the tailpipe for the first couple of minutes. I don't see or smell anything from the blow by, just an oil drip which could be just what's thrown up? No compression test done. With the boring and surfacing of the block and head I have no idea what compression readings I should expect.
          1949 2r5 28196
          170ci 6cyl
          4spd

          Comment


          • #6
            If local laws don't prohibit, a draft tube is most efficient. I would prefer to not reintroduce exhaust gases into the engine. An engine in good condition will not emit any visible vapor. Exhaust smoke, is from valve guides and crankcase smoke is from rings. You do not have a ring or cylinder issue only valve guides. There are three options, oversize valve stems and ream the block to fit, use standard valves and install new guides or live with it.

            Comment


            • #7
              [QUOTE=Old Radio Tech;951017..... New E286F .06 over piston set (measured 3.0573). Hastings 472 .06 ring set. ...............[/QUOTE]

              If plain 472 I believe the compression rings are type 032, barrel faced iron.

              The part number would be 2C472 if it used type 362 chromed barrel faced top compression rings.


              pages 5 and 222-224 here -
              https://www.hastingsmfg.com/Master_C...Master2012.pdf

              Comment


              • #8
                What did the old timer suggest to you was proper break-in driving?

                Either he, or you, should have subjected a warmed up engine to several brief bursts of heavy throttle at mid revs, separated by several minutes of easy running to let things cool off. Hastings, like other ring manufacturers, says so.

                " 30 to 50 mph, at least 10 times " !!!

                https://www.hastingsmfg.com/ServiceT..._procedure.htm

                But It might be more comfortable and "safer" if you ask the old timer's advice/permission.

                Regardless, I'd repeat the process, if the engine were mine ( but I would have been the one to assemble it).
                Actually, I'd repeat the process several times even if I thought the rings were fine, just for the fun of it, under the pretext of gently "easing down" any other high/tight spots on the piston skirts, crank, and accelerator linkage.
                Last edited by Dan Timberlake; 10-19-2015, 08:08 AM.

                Comment


                • #9
                  Exhaust smoke, is from valve guides
                  Usually true.

                  on a cold start I get oil smoke from the tailpipe for the first couple of minutes.
                  Here's where it gets difficult. Exhaust smoke from valve guides never goes away. It will actually get worse as the oil thins out when hot. One test for valve guide wear is to coast down a long hill in gear and then accelerate at the bottom. Worn guides usually will suck up and burn out a lot of oil under that condition.

                  You do not have a ring or cylinder issue only valve guides. There are three options, oversize valve stems and ream the block to fit, use standard valves and install new guides or live with it.
                  The Champion engines also are known to wear out the lifter bores. When they do, the extra clearance floods the valve cavity with oil, thus putting too much oil next to the valve guides. Low oil pressure usually accompanies worn lifter bores.

                  No compression test done. With the boring and surfacing of the block and head I have no idea what compression readings I should expect.
                  On a newly rebuilt engine, the compression readings should be on the high side of the range given in the Shop Manual. You didn't give the year, but 115# is in the ball park.

                  jack vines
                  PackardV8

                  Comment


                  • #10
                    New valve guides, lifters, springs, keepers. Problem is I didn't have it the 1st 200 miles and don't know how it was treated. speedo not working so I'm not even sure on the 200 miles or not. 50 mph is about tops. Invoice just says 472 for the rings. So Dan - 30-50mph in high gear, hold at 50 mph for how long and the ease back down? repeat

                    - - - Updated - - -

                    it's a 1949
                    1949 2r5 28196
                    170ci 6cyl
                    4spd

                    Comment


                    • #11
                      Going to talk to the old timer today about break-in(whether he did or left that to customer). If he did, should I perform the break-in again?
                      1949 2r5 28196
                      170ci 6cyl
                      4spd

                      Comment


                      • #12
                        Originally posted by Old Radio Tech View Post
                        Going to talk to the old timer today about break-in(whether he did or left that to customer). If he did, should I perform the break-in again?
                        BREAK-IN PROCEDURE

                        1. Make a test run at 30 miles per hour and accelerate at full throttle to 50 miles per hour. Repeat the acceleration cycle from 30 to 50 miles per hour at least ten times. No further break-in is necessary. If traffic conditions will not permit this procedure, accelerate the engine rapidly several times through the intermediate gears during the check run. The object is to apply a load to the engine for short periods of time and in rapid succession soon after engine warm up. This action thrusts the piston rings against the cylinder wall with increased pressure and results in accelerated ring seating.

                        Following that,
                        Drive vehicle normally but avoid sustained high speed during the first 100 miles.
                        At no time should the engine be lugged. Lugging is said to exist when the engine does not respond when you twist the throttle.

                        Taken from Hastings piston ring website
                        jack vines
                        PackardV8

                        Comment


                        • #13
                          Cylinder pressure is the "only"...thing that breaks in rings..! Chrome rings need a LOT of cylinder pressure.
                          If you have any freeways or open highways where you can floor the throttle, in high gear, till you reach max mph...use it. You'll need to do this several times. Never drive the car at a steady pace/throttle until the rings are broken in. Let the traffic get far ahead of you, then with a hard throttle...catch-up. As your mechanic noted, it may take 1000 to do this type of driving.
                          JUST DRIVING the car will NOT break in the rings. The rings need that cylinder pressure behind them, to force them into the cylinders to make them mate properly.

                          And no, I would NOT connect a PCV system "until" the rings are broken in. Once they are fully broken in, then and only then would I connect a PCV system.
                          Why...because this forces oil back into the combustion chambers that hampers the ring breakin, it destroys the spark plugs, it causes detonation/preignition, and cruds up the chambers in general.

                          Mike

                          Comment


                          • #14
                            OK, the old timer(I say old timer and I'm 65) said break-in was done as per Manufacturer before the vehicle was given to the customer, and I'm confident he's being honest. I have three questions now. Doing the 30-50 version, do I hold it at 50 or just run it up and then ease back to 30 or get off the gas completely? I can't confirm and the old timer doesn't remember whether the rings were chrome or not. The invoice lists the PN as 472 .06 P-Rings. So if I can't confirm would I be doing more damage than good on regular rings if I went with Mikes option. And the motor may now have 300 miles on it. And should I do another round of Break-in? Will it help? This thread is evolving.
                            Last edited by Old Radio Tech; 10-19-2015, 01:56 PM.
                            1949 2r5 28196
                            170ci 6cyl
                            4spd

                            Comment


                            • #15
                              I don't think several dozen short bursts of heavy throttle would hurt any properly machined, cleaned, and assembled and reasonably well-tuned engine.

                              The purpose of the limited duration heavy throttle is to avoid excessive localized cascade heating of the "high" spots. That would thin the oil in the immediate vicinity of the high spot, allowing the parts to rub harder, get hotter, and the situation to escalate and the parts to possibly score or gall, and possible even seize. Thousands of miles of gentle running can not un-do that kind of physical damage.
                              Several minutes of rest time after each heavy throttle lets things cool down and maybe new oil to sneak in, and possibly flush out the debris from any small minor high spots buffed down. That's my theory, anyhow.

                              Comment

                              Working...
                              X