Results 1 to 25 of 25

Thread: Loosening piston rings after 39 years?

  1. #1

    Loosening piston rings after 39 years?

    My '56 Corvette (265ci V8) was stored in the CA desert for about 39 years, inside a garage mind you, NOT outside. The original engine was rebuilt and had only about 2,000 miles on the rebuild when the car was parked. It did not take much to get the engine running and after a few months I have now gone through everything and it's running better than ever.

    BUT, not all of the upper piston rings appear to be sealing yet. I am getting some blowby when running (smoke coming out of breather tube) and I can hear out the exhaust that it's the passenger side. I haven't done a compression check yet, I kind of don't want to know lol.

    I first tried Redline with Auto-Rx for about 700-800 miles. After no change and having to replace the oil after a rear main seal leak, I have added some MMO to the crank case and gas tank. I'm still running Redline as it has the right amount of zync & phos for a flat tappet cam.

    Anyway, I have just gone through a full tank of gas with the MMO in the crank case and gas tank. It seems to be helping a little bit but not enough. I'm going to be pulling my intake in a week and I was going to pull the spark plugs and fill the combustion chambers with MMO and let sit for a week. Then crank the engine with no plugs to blow out the left over MMO and fire it back up with the new intake and carb installed.

    Do you guys have any other tips for me you can think of?

    Thanks! Alex
    www.TheFoat.com/92GTA - 1992 Pontiac Trans Am GTA. 2008 GMC Acadia

  2. #2
    Senior Member Friartuck's Avatar
    Join Date
    Sep 2002
    Location
    Red Bank, New Jersey
    Posts
    634
    Images
    5

    Re: Loosening piston rings after 39 years?

    Alex,
    Not every engine problem can be solved with a "snake oil" remedy, however, I have had good success with Seafoam. Seafoam is an gas and crankcase oil additive and been around for quite a few decades, just not widely known. Find it in you area or get it via the web. Accept no substitues.

  3. #3

    Re: Loosening piston rings after 39 years?

    Quote Originally Posted by Friartuck View Post
    Alex,
    Not every engine problem can be solved with a "snake oil" remedy, however, I have had good success with Seafoam. Seafoam is an gas and crankcase oil additive and been around for quite a few decades, just not widely known. Find it in you area or get it via the web. Accept no substitues.
    Yeah I'm just trying everything before I rehone and rering.

    I used 2 spray cans and half a liquid can of SeamFoam down through the carbs 2 different times and it cleaned it up but did not solve the issue. I haven't tried it in the crank case or gas tank yet. I have found SeaFoam to be great for cleaning but not for rust/lubrication issues.
    www.TheFoat.com/92GTA - 1992 Pontiac Trans Am GTA. 2008 GMC Acadia

  4. #4
    Member
    Join Date
    Sep 2010
    Location
    East Earl PA
    Posts
    38

    Re: Loosening piston rings after 39 years?

    Try putting Marvel Mystery oil in each cylinder and let it sit for a few days and then blow it out. I have had great luck with this stuff. You can add to gas and to the oil if you like. However, the best and quickest is going to be pouring it directly into each cylinder.

    Scot
    1940 Olds Series 90
    1981 MB 300SD
    1981 El-Camino

  5. #5

    Re: Loosening piston rings after 39 years?

    Quote Originally Posted by scot View Post
    Try putting Marvel Mystery oil in each cylinder and let it sit for a few days and then blow it out. I have had great luck with this stuff. You can add to gas and to the oil if you like. However, the best and quickest is going to be pouring it directly into each cylinder.

    Scot
    Thanks for confirming!
    www.TheFoat.com/92GTA - 1992 Pontiac Trans Am GTA. 2008 GMC Acadia

  6. #6
    Senior Member
    Join Date
    Jan 2006
    Location
    Oregon
    Posts
    984
    Images
    14

    Re: Loosening piston rings after 39 years?

    ATF might be a good choice to soak the cylinders with, I have had luck with it. another trick is to start it up with the radiator covered and let the heat gauge rise to almost hot and cool for a few cycles. Sometimes the extra heat makes things move a bit.

  7. #7
    Senior Member
    Join Date
    Mar 2008
    Location
    Texas
    Posts
    1,908

    Re: Loosening piston rings after 39 years?

    If the Marvel Mystery oil treatment doesn't work drain the oil out of the crankcase and fill it with Kerosene. Run the engine at around 1200 rpms for fifteen to twenty minutes, then drain out the kerosene and replace the oil filter and put in fresh 10W-30 oil. Kerosene is a light oil and will provide adequate lubrication for the short time the engine is being ran. FYI, I've done this procedure many times, most typically to wash out sticking lifters and never had an engine suffer bearing damage from doing it.

    Once you have refilled the crankcase with fresh oil and put on a new filter, take that sucker out on the road and red line it a few times because all the rings should be very loose and some may even need to re-seat. When you get back, drain the oil again and change the filter and refill the crankcase with HD-30 oil to keep from screwing up your cam.

    Jim
    OCA, LCOC, AACA
    1956 Cadillac Eldorado Seville
    1957 Cadillac Eldorado Seville
    1958 Mercury Montclair 4dr
    1962 Oldsmobile Starfire (2)
    1976 Lincoln Mark IV (2)
    1978 Lincoln Continental Town Car
    1987 Lincoln Mark VII LSC
    1990 Ford F-150
    1995 Ford E-150 custom high top
    2003 Lincoln Town Car

  8. #8

    Re: Loosening piston rings after 39 years?

    It may just need more breakin miles. An overnight soak of MM down the spark plug holes may help. Then drive it. 50 miles at a time or more if possible. Do another 2000 miles or so and if there is no change you may have to tear the engine down and install new rings.

    Incidentally a friend of mine bought a late 60s Chev pickup in similar condition. It started and ran well but burned oil. He drove it around town for several years with no problems. When he tore it down all the rings were still stuck in the grooves. He replaced the rings and honed the cylinders with a bottle brush hone and it ran like a new one.

    I suspect if he had taken some long trips instead of puttering around town the rings might have freed up.

  9. #9
    Senior Member Marty Roth's Avatar
    Join Date
    Dec 2007
    Location
    NEW ORLEANS, LOUISIANA
    Posts
    2,615

    Re: Loosening piston rings after 39 years?

    The tip about kerosine in the crankcase really works - I've done it !

    A safer alternative is to use half 10W30 and half ATF -- 3 or 4 successive oil changes with a fresh filter - let it idle at 1500 - 1800 rpm for 20 minutes with the radiator half-blocked with cardboard to have it run warm, but not overheat.

    This will usually free-up stuck rings, lifters, (and maybe even the lollipop stuck to the upholstery).

    MARTY ROTH__________NEW ORLEANS, LA

    AACA DIRECTOR
    VP-DEVELOPMENT & SUPPORT-CENTRAL DIV.
    SENIOR-MASTER JUDGE
    AACA LIFE MEMBER

    1930 PACKARD 733 7-PASSENGER TOURING
    1934 BUICK 34-57 SIDEMOUNTED SEDAN
    1937 BUICK 80C ROADMASTER PHAETON
    1941 CADILLAC CONVERTIBLE
    1954 CADILLAC CONVERTIBLE
    1970 CADILLAC CONVERTIBLE
    1986 CHEVY SUBURBAN 2500 454ci
    1988 BMW 528e
    1988 CORVETTE CONVERTIBLE
    1994 CADILLAC FLEETWOOD
    1995 CADILLAC FLEETWOOD
    2005 CHRYSLER CONVERTIBLE
    1954 U-HAUL 4x6 TRAILER

  10. #10
    Sr Mbr -- BCA 20811
    Join Date
    Dec 1999
    Location
    DFW, TX
    Posts
    5,781

    Re: Loosening piston rings after 39 years?

    Ring "seating" should have already happened, even if you put a rough hone finish on the cylinder walls when the engine was rebuilt. On a rebuild, with a seasoned block, the bore will usually stay more round so there's less issues with the rings conforming to the cylinder walls' shape. Therefore, ring seating (initial and final) happens pretty quick.

    The oil consumption will be related to the oil rings rather than the compression rings, as it's the oil rings that scrape the oil from the cylinder walls (as oil control). You can have good compression and still have oil rings that aren't working very well.

    Of course, we're presuming that the rings were all gapped to specs by the engine builder, rather than just being installed "out of the box". AND that some sort of "low drag" racing-style piston rings were not used, rather than the normal-tension stock-style rings.

    Some of the "soaks" mentioned might work . . . I've never needed to do that . . . but the more "oily" they are, probably the better. IF you're after more "flow", then regular motor oil in the lighter 0W-30 or 5W-20 viscosity ranges might be better. This way, you can add only some of the "cam protection additives" and run the lighter oil for quite some time, with no issues of multiple oil changes to get other flush fluids out of the system. CompCams and Crane now make such additives. Varying the rpms while driving, just as the older new car break-in procedures used to recommend, can help get the rings moving again, IF that's really the issue causing problems. IF you use synthetic oil, you can probably do without the oil additive.

    ALSO, don't forget that oil consumption issues can also be due to valve guide clearance issues, plus the valve stem seals themselves. Too much guide clearance will wear the seals much sooner and also allow more oil into the head ports.

    Regards,
    NTX5467

  11. #11
    Senior Member packards42's Avatar
    Join Date
    Sep 2001
    Location
    Washougal, Washington
    Posts
    1,183
    Images
    7

    Re: Loosening piston rings after 39 years?

    My good friend, that does ancient tractors, use diesel and AFT in teh clyinders, tows them home, then soak for 1-6 months, until they turn over, then fire them up, and then decides what to do, park-m, run-m, overhaul-m/ we talking 100 tractors in the shed.

    I used diesel to free up a $200 NOS overdrive cable. soaked for 30 days, then I worked it from the pull end about 1/2 hour a night, progressively geting about 1/4 inch in the beginning. Continuing the process of soaking and working about 30 minuted, it took about another month to have working as good as new. I had to use vise grips in the beginning to pull the cable.
    1. 42 Packard Seven passenger Limo

    42 Packard seven passenger sedan parts only, maybe an airport limo
    42 Packard formal, a basket case, restorable and complete.
    40 Packard 160 -127 inch, , some surface little rust restorable

    Wanted on rear deck Air Conditioner Vent to complete the 42 limo.

    Wanted one factory Air Conditioners

    Want 6 or 8 door Airport limo any year, any make pre WWII.

    we are reproducing the Air condioner trunk boxes

  12. #12

    Re: Loosening piston rings after 39 years?

    Thanks for the tips and info everyone!

    I'm going to add some more information...

    I don't seem to have oil consumption issues, it more of a blow-by, low compression in a couple of cylinders issue. When the original engine was rebuilt before being stored, it was built for racing by Fains Machine in Ventura CA. It only ever saw 1 drag race and about 2,000 street miles before going into storage. The 2nd owner that had Fain do the work said they went .030" over, used new pistons, and built it "loose" for racing. So whatever "loose" meant in 1965 to Jimmy Fain, I'm not sure.

    As of today, I have another 300 miles or so of driving with the MMO in the oil and fuel since my initial post. It has been allot of mountain driving in 2nd and 3rd gear so I have been keeping the RPMs constantly changing and staying in gear slowing down or going down hill.
    www.TheFoat.com/92GTA - 1992 Pontiac Trans Am GTA. 2008 GMC Acadia

  13. #13
    Senior Member
    Join Date
    Mar 2008
    Location
    Texas
    Posts
    1,908

    Re: Loosening piston rings after 39 years?

    Quote Originally Posted by 92GTA View Post
    Thanks for the tips and info everyone!

    I'm going to add some more information...

    I don't seem to have oil consumption issues, it more of a blow-by, low compression in a couple of cylinders issue. When the original engine was rebuilt before being stored, it was built for racing by Fains Machine in Ventura CA. It only ever saw 1 drag race and about 2,000 street miles before going into storage. The 2nd owner that had Fain do the work said they went .030" over, used new pistons, and built it "loose" for racing. So whatever "loose" meant in 1965 to Jimmy Fain, I'm not sure.

    As of today, I have another 300 miles or so of driving with the MMO in the oil and fuel since my initial post. It has been allot of mountain driving in 2nd and 3rd gear so I have been keeping the RPMs constantly changing and staying in gear slowing down or going down hill.
    If you have blow-by, you have an oil loss issue. You'll be finding it in your air cleaner or oozing out the breather cap. As a personal opinion, an engine built loose for drag racing makes it basically useless for a street machine. Since Fain is still in business in Ventura I think I'd give him a call and see if there is a remote possibility he still has a copy of the blue print for that engine.

    Jim
    Last edited by Jim_Edwards; December 10th, 2010 at 11:29.
    OCA, LCOC, AACA
    1956 Cadillac Eldorado Seville
    1957 Cadillac Eldorado Seville
    1958 Mercury Montclair 4dr
    1962 Oldsmobile Starfire (2)
    1976 Lincoln Mark IV (2)
    1978 Lincoln Continental Town Car
    1987 Lincoln Mark VII LSC
    1990 Ford F-150
    1995 Ford E-150 custom high top
    2003 Lincoln Town Car

  14. #14

    Re: Loosening piston rings after 39 years?

    Quote Originally Posted by Jim_Edwards View Post
    If you have blow-by, you have an oil loss issue. You'll be finding it in your air cleaner or oozing out the breather cap. As a personal opinion, an engine built loose for drag racing makes it basically useless for a street machine. Since Fain is still in business in Ventura I think I'd give him a call and see if there is a remote possibility he still has a copy of the blue print for that engine.

    Jim
    I do get smoke out of my breather tube when the engine is running. It seems to use very little oil though and my plugs don't foul.

    Fain was still in the garage of his house back in 1964/65 and would have no records. He built this engine for his brother-in-law at the time (who was the 2nd owner). I have tried emailing him to see if he remembers anything about the car but I have never gotten a response.

    The engine has fair street manners after setting the timing right for the cam and getting the carbs adjusted accordingly with a correct heat range plug. I'm this weekend removing the 2x4 setup Fain installed and putting the original intake and rebuilt carb back on and I'll be tuning that accordingly too.

    Aside from the little bit of smoke out the breather tube and the tone of the passenger side exhaust being slightly off compared to the left, I don't really have much of an issue. Not enough to justify tearing it apart at this time anyway.

    I'm going to fill the combustion chambers with MMO and let it sit for a couple or a few weeks just to be sure eerything is as good as it can be. Then I'll drive the heck out of it and do a compression check and go from there. If I have a cylinder that is too much out of spec compared to the rest, then I will consider tearing it apart.
    www.TheFoat.com/92GTA - 1992 Pontiac Trans Am GTA. 2008 GMC Acadia

  15. #15
    Senior Member
    Join Date
    Mar 2008
    Location
    Texas
    Posts
    1,908

    Re: Loosening piston rings after 39 years?

    Quote Originally Posted by 92GTA View Post
    I do get smoke out of my breather tube when the engine is running. It seems to use very little oil though and my plugs don't foul.

    Fain was still in the garage of his house back in 1964/65 and would have no records. He built this engine for his brother-in-law at the time (who was the 2nd owner). I have tried emailing him to see if he remembers anything about the car but I have never gotten a response.

    The engine has fair street manners after setting the timing right for the cam and getting the carbs adjusted accordingly with a correct heat range plug. I'm this weekend removing the 2x4 setup Fain installed and putting the original intake and rebuilt carb back on and I'll be tuning that accordingly too.

    Aside from the little bit of smoke out the breather tube and the tone of the passenger side exhaust being slightly off compared to the left, I don't really have much of an issue. Not enough to justify tearing it apart at this time anyway.

    I'm going to fill the combustion chambers with MMO and let it sit for a couple or a few weeks just to be sure eerything is as good as it can be. Then I'll drive the heck out of it and do a compression check and go from there. If I have a cylinder that is too much out of spec compared to the rest, then I will consider tearing it apart.
    Oil fouling of plugs is not a characteristic common to an engine having blow-by issues. Not wanting to magnify the issue out of proportion, you have to realize that blow-by is not necessarily a problem for engines used in drag racing, though from time to time if blow-by is really excessive amounts of unburned fuel getting into the crankcase has been known to cause an explosion in the crankcase, blowing the pan right off the engine and making for one hell of a fire. An engine is built "loose" to prevent seizing in a 1/4 mile run, this blow-by is a characteristic of engines built for drag racing, most particularly if the engine is being raced with no coolant, no water pump, and no radiator.

    If my vehicle, I'd be running leak down tests on all cylinders to determine just how bad the blow-by may be. Realistically, you may have to have that engine re-worked to make it a safe to drive on the streets vehicle.

    When you pull that intake to get it back to a single 4bbl set up don't be surprised if you see a lot of oil where it shouldn't be because of the amount that is probably being forced passed the PCV valve, assuming it was fitted with one to comply with California emissions standards back in 1960 something. If that engine still has a vent tube you may want to see just how evident oil is there and under the car. I'd also stick my nose close enough to the tube (again if it still has one) to see if it smells more like gasoline than oil. It doesn't take much fuel dilution in the oil to ruin a crankshaft due to improper lubrication of the mains and rod bearings.

    Jim
    Last edited by Jim_Edwards; December 10th, 2010 at 14:15.
    OCA, LCOC, AACA
    1956 Cadillac Eldorado Seville
    1957 Cadillac Eldorado Seville
    1958 Mercury Montclair 4dr
    1962 Oldsmobile Starfire (2)
    1976 Lincoln Mark IV (2)
    1978 Lincoln Continental Town Car
    1987 Lincoln Mark VII LSC
    1990 Ford F-150
    1995 Ford E-150 custom high top
    2003 Lincoln Town Car

  16. #16

    Re: Loosening piston rings after 39 years?

    No PCV, these cars weren't made with them.

    I smell my dipstick constantly and never smelled fuel. I'll have to monitor the vent tube and see how much is escaping there.

    Thanks for going over how drag engines act and what loose means from back then, I'm clueless as I'm only 30.

    Alex
    www.TheFoat.com/92GTA - 1992 Pontiac Trans Am GTA. 2008 GMC Acadia

  17. #17
    Senior Member
    Join Date
    Mar 2008
    Location
    Texas
    Posts
    1,908

    Re: Loosening piston rings after 39 years?

    Quote Originally Posted by 92GTA View Post
    No PCV, these cars weren't made with them.

    I smell my dipstick constantly and never smelled fuel. I'll have to monitor the vent tube and see how much is escaping there.

    Thanks for going over how drag engines act and what loose means from back then, I'm clueless as I'm only 30.

    Alex
    That almost sounds obscene........

    Probably a very good chance when that engine was built up it got a set of Jahn's racing pistons and an Isky cam. It could be an interesting trip back in time to tear that engine down just to see what it really has in it.

    Just watch that oil closely. Drag racers don't worry about oil dilution all that much since they'll often change the oil between runs. We used to consider it a good run if oil had blown out of the engine every imaginably possible place it could.

    Jim
    OCA, LCOC, AACA
    1956 Cadillac Eldorado Seville
    1957 Cadillac Eldorado Seville
    1958 Mercury Montclair 4dr
    1962 Oldsmobile Starfire (2)
    1976 Lincoln Mark IV (2)
    1978 Lincoln Continental Town Car
    1987 Lincoln Mark VII LSC
    1990 Ford F-150
    1995 Ford E-150 custom high top
    2003 Lincoln Town Car

  18. #18
    Sr Mbr -- BCA 20811
    Join Date
    Dec 1999
    Location
    DFW, TX
    Posts
    5,781

    Re: Loosening piston rings after 39 years?

    Typically, "loose" for racing would mean piston skirt clearance, possibly a little more valve stem to guide clearance, and main/rod bearings that were near the top of the clearance spec, too. Piston rings usually are not part of that mix, though, nor might there have been the low-tension rings in that earlier timeframe.

    Normal piston skirt clearance is about .002", but Chevy ran their light duty pickup truck engines and forged piston Z-28 motors at about .004" . . . looser due to the fact that these engines might well encounter "heavy duty use", compared to a normal car engine. About in the early 1970s, the light duty pickup truck motors started using the "car" piston clearance specs, though.

    You CAN convert your engine to a PCV system, with the same parts that they used on the '67 motors. A "cap" that bolted onto the block where the draft tube attached, with a hose nipple for the PCV line and an inline PCV valve. Not very hard to do.

    IF the engine has a very big camshaft in it, to complement the 2x4bbl situation, then you might well have issues getting the engine to idle correctly with an original OEM carb. IF you can't get it to idle right, you might need to drill some small holes in the primary throttle blades so the original relationship between the throttle plates and the idle and transition fuel slots is maintained. The Rochester carb book tells how to do that. Hopefully, you'll not need to do that.

    I don't see any reliability issues in this situation. Nothing should blow up, from what I've seen, but it might idle a little rougher than you might like to sit in slow moving traffic with. Might want to try a more modern electronic ignition upgrade . . . Pertronix or similar, which might make the idle situation a little easier to live with.

    Just some thoughts . . .
    NTX5467

  19. #19
    Senior Member
    Join Date
    May 2008
    Location
    The Hotel California
    Posts
    1,208

    Re: Loosening piston rings after 39 years?

    Just a side note regarding Synthetic Oils: No synthetics have the requisite Zinc / Phosphate to combat flat tappet/cam lobe fatigue. Chemically they have an inability as a carrier to bind these cations in solution. Also there is a lot more petro-chemistry going on as well that does not make synthetics the love child for our flat tappet engines.

    Yes synthetics have higher burn rates and lower temperature fluid state properties, but lack the proper structure to bind with Zinc / Phosphate molecules to be used as a carrier medium for them for OUR type of engines.
    David - BCA # 45902 - 1957 Roadmaster 76A Coupe, 60K Survivor - RR & 731 and 1957 Roadmaster Model 75 4-door w/58K

    ..." Silly monkey Master, he continues to hold onto the fruit in the jar when the gardens outside are full with fruit - he should just let it go".. " I am pleased Grasshopper that you are wiser than the monkey "..." Oh I am much wiser Master" ..." I would hope you remain so, and know when it is time to let go of those things which no longer serve you but force you to serve them"

  20. #20

    Re: Loosening piston rings after 39 years?

    Quote Originally Posted by buick man View Post
    Just a side note regarding Synthetic Oils: No synthetics have the requisite Zinc / Phosphate to combat flat tappet/cam lobe fatigue. Chemically they have an inability as a carrier to bind these cations in solution. Also there is a lot more petro-chemistry going on as well that does not make synthetics the love child for our flat tappet engines.

    Yes synthetics have higher burn rates and lower temperature fluid state properties, but lack the proper structure to bind with Zinc / Phosphate molecules to be used as a carrier medium for them for OUR type of engines.
    Redline. It actually has even more zinc/phos than required.
    www.TheFoat.com/92GTA - 1992 Pontiac Trans Am GTA. 2008 GMC Acadia

  21. #21

    Re: Loosening piston rings after 39 years?

    In the fifties there was an article in a hot rod magazine about forged racing pistons. The author stated that he had a set of solid skirt, forged aluminum racing pistons in the Corvette he used for every day transportation. They required .012 clearance when cold. He said he had driven it this way for 30000 miles with no problems from oil burning or piston slap. The secret was to fit the pistons with the required clearance then knurl the skirts.

    If your Corvette was built for racing it may have something like that. It may also have Grants plain cast iron rings which were a favorite of hot rodders. The worked well and broke in quickly but they only had a life of 30000 to 50000 which did not bother racers in the least.

  22. #22
    Senior Member
    Join Date
    Mar 2008
    Location
    Texas
    Posts
    1,908

    Re: Loosening piston rings after 39 years?

    Quote Originally Posted by Rusty_OToole View Post
    In the fifties there was an article in a hot rod magazine about forged racing pistons. The author stated that he had a set of solid skirt, forged aluminum racing pistons in the Corvette he used for every day transportation. They required .012 clearance when cold. He said he had driven it this way for 30000 miles with no problems from oil burning or piston slap. The secret was to fit the pistons with the required clearance then knurl the skirts.

    If your Corvette was built for racing it may have something like that. It may also have Grants plain cast iron rings which were a favorite of hot rodders. The worked well and broke in quickly but they only had a life of 30000 to 50000 which did not bother racers in the least.

    Dang that's a trip down memory lane! I had totally forgotten about Grant pistons. Grant is still around but not producing pistons, only rings.

    I'd sure love to get that engine on a stand to see what's really in it. I wouldn't be shocked to see an early Isky roller cam/roller lifter setup inside that puppy.

    Yeah, for all you youngsters I said roller cam. Isky was producing roller cams for push rod engines back in the mid 1950s and Ed Iskendarian patented the roller lifter and perfected methods for eliminating cam walk. Aah, I can smell the nitro and burning Mickey Thompson's now!
    Last edited by Jim_Edwards; December 12th, 2010 at 10:50.
    OCA, LCOC, AACA
    1956 Cadillac Eldorado Seville
    1957 Cadillac Eldorado Seville
    1958 Mercury Montclair 4dr
    1962 Oldsmobile Starfire (2)
    1976 Lincoln Mark IV (2)
    1978 Lincoln Continental Town Car
    1987 Lincoln Mark VII LSC
    1990 Ford F-150
    1995 Ford E-150 custom high top
    2003 Lincoln Town Car

  23. #23
    Sr Mbr -- BCA 20811
    Join Date
    Dec 1999
    Location
    DFW, TX
    Posts
    5,781

    Re: Loosening piston rings after 39 years?

    When the whole zddp issue was first mentioned, it was the recommendation of Competition Cams that for warranty coverage on their replacement camshafts, that either Shell Rotella T (normal oil, but diesel-spec, which is 15W-40 viscosity) OR synthetic oil -- THEIR recommendation back then.

    As this whole situation seemed to come from the aftermarket engine parts side of things, I initially suspected that the replacement camshaft people were not putting quite as much Parkerizing (surface hardening treatment) on their cams as the OEMs did. As CompCams and others now have their own motor oils and/or oil additives, plus a noted improved surface hardness, my gut suspicion seems to have been proven correct.

    In researching things, I found other significant camshaft lobe wear issues on racing camshaft/engine situations. High speed, high valve spring pressures, much taller and steeper lobe shapes for the higher horsepower applications these engines were used in. Contrast that to and "OUR" engines . . . which very seldom exceed 3000rpm, have very much smaller lobe shapes (lower valve lifts) with similarly softer valve spring pressures (high spring pressures are NOT needed in these situations), and (unless it's a replacement camshaft) all of the initial wear issues of the lifters/tappets mating with their respective cam lobes has long since happened. Therefore, many of the issues with lobe/tappet wear are NOT in "OUR" engines nearly as much as they are in higher-performance racing engines which are needed to run for several hundred miles at "high load, high rpm" and finish the race . . . or win it.

    Hidden in the back of the Mobil website is a list of their current motor oils and the levels of zddp in each of them. This includes their many variations of Mobil 1 synthetic oil. Many of the newer-OEM-spec oils have less than 1000ppm of zddp in them, but that seems to be the "floor" of zddp levels for synthetic "SL" rated motor oil. This would also include the VW spec for some of their diesel engines which run the injection pump off of one cam lobe -- an engine which can suffer cam lobe wear if the approved motor oil is not used.

    If you look in the Virgin Oil Analysis' posted on the www.bobistheoilguy.com website, you'll find that, generally, even the latest diesel motor oils still have a good bit of zddp in them, with almost NO decrease with the latest formulations. More than 1000ppm, as I recall, which means that with plenty of zddp in a synthetic base, it should be fine for any flat tappet engine. Typically, the normal diesel oils have more zddp as they are not synthetic oils. PLUS, it needs to be noted that there are other anti-wear additives other than zddp, which can fully protect cam lobes, too, just that zddp was the anti-wear additive of choice for many years (and generally the least expensive one that worked).

    Even in the "old days", it was imperative to use plenty of the cam break-in lube ( I used both the black, moly paste on the lobes and usually two cans of the GM EOS Concentrate to lube the lifters and then pour over the cam lobes when I was done), plus the requisite 30 minutes of run time at varying rpm levels (so the cam lobes would be lubed with splash oil from the crankshaft). If that procedure was not followed for flat tappet cams, they would usually fail even with oils which allegedly had sufficient zddp in it! Back then, too, as now, if you didn't buy the lifters from the cam manufacturer, you had not warranty anyway. BUT successful engine builders knew where to buy the "stuff that worked" and when combined with the specified cam break-in lube and procedures, things worked just fine and the cams/lifters lasted many hundreds of thousands of miles.

    Consider, too, that many vintage engines were built when there was minimal zddp in the oil, BUT it was also common to have 2000 mile oil change intervals. Those quicker oil change intervals were necessary not only to remove accumulated gunk from the unfiltered (generally) motor oil but also to keep things lubed with oil whose base stocks and additive packages had not broken down from use . . . which would result in more engine wear. In that orientation, I highly suspect that even the most allegedly zddp-deficient modern motor oil would work just fine in an older engine, if you follow the earlier oil change intervals rather than the more recent longer oil change intervals. With the way that some vintage engines are used, they might need 1000 mile oil changes to keep the oil from getting too gunked-up anyway, even with the modern stuff--the old "short trip, low speed" orientation where the engine never does really get up to operating temperature for a long enough time to cook out the condensates and such which might be in the motor oil as combustion byproducts.

    If you want to use a non-syn, straight-viscosity 30 motor oil, you'll most usually find those in "SL" ratings at the highest. "SL" is generally agreed to be the highest API rating to use with flat tappet cams. I believe that Royal Purple syn oil is also a "SL" oil, as are some other non-OEM-recommended viscosity motor oils. Seems like it took Amsoil a good while to get above the "SL" rating, too.

    Just some thoughts,
    NTX5467

  24. #24

    Re: Loosening piston rings after 39 years?

    Somehow discussions like this all get steered toward motor oil specs. The original question was about the blow-by on his engine and I vote for the Seafoam remedy. If there truly is no mechanical problem (rings properly sized, no restrictions in the ring grooves) I think a Seafoam soak (like he was proposing with MMO) would have as good a chance of reducing the blow-by as anything. Then change the oil and run the engine HARD. Joe

  25. #25

    Re: Loosening piston rings after 39 years?

    Memories ------ Back in 1969 I built a 427 Ford for a 41 Willys.... Used Jahns pistons and grant rings.. I bored the block to what Jahns told me to do.. MADE PHONE CALLS to confirm what they told me.... Seemed they were giving me the numbers for a .040 piston set and not for the .030 set they sent me.... They assured me the measurments were correct...

    The pistons fell through the holes..... The engine rattled like CRAZY! But that car ran HARD! Yes it had blow-by.. But it was they way we built them back then.. LOOSE... this one was REAL LOOSE... I think the Corvette engine was built the same way.. LOOSE... In the 60's and 70's the Corvettes were still used as drag race cars... They were not the restored prima-donnas we see today...

    By the way, the 41 Willys was a street legal (sorta) sedan that was also able to run in the high 10's. On the street it was very well known. The wild wheel standing RODENT 1 is legendary here in the Napa Valley.

    The car was Maroon with Black fenders, had fiberglass front end, engine set back, 9" Ford rear end, we ran GoodYear blue streaks on the street with 12 spoke Americans up front. The 427 had the 3X2 carb set and Cobra engine trim. It has the letters, "Rodent 1" across each side and a mural of a Rodent grasping a Cobra on the trunk.

    One guy tells me he flagged off the car one race day against a motorcycle, he dropped his arms, the Willys came off the ground and all he saw was the bottom of the car with headlights pointed to the sky...... The car came back down and was sideways when it went past him... he thought he was a gonner! The Willys won that match..

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Old piston rings
    By '53 Windsor in forum Technical
    Replies: 2
    Last Post: August 22nd, 2005, 10:16
  2. Where to get piston rings?
    By c.johnson in forum Technical
    Replies: 16
    Last Post: July 15th, 2005, 12:24
  3. New piston, old rings ok?
    By Packrat in forum Technical
    Replies: 3
    Last Post: June 12th, 2004, 21:07
  4. Piston rings for 425
    By in forum Buick - General
    Replies: 2
    Last Post: June 25th, 2002, 09:19
  5. NOS PISTON RINGS
    By BUICK RACER in forum Buick - Buy/Sell
    Replies: 2
    Last Post: February 2nd, 2001, 02:14

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •