1965: Big Problems

Discussion in 'Ranchero Tech Help' started by AimlessMoto, Aug 9, 2020.

  1. AimlessMoto

    AimlessMoto In Overdrive

    Messages:
    534
    Location:
    Townsend, MA
    289, C4, stock engine, holley 4bbl

    12 degrees initial, 34 total...

    Runs hot when over 85 out...

    Has had a slight main seal leak and a slight intake valley front and rear leak for a while... also likes to spit out of the valve cover breather on the drivers side... has PCV on the passenger side.

    That said:

    Highway... 80mph+ for an extended period... was running amazing. Went to floor it and it started to ping. AFR was in the low 12s, RPM in the 4000-4200 range. Backed off it. Slowed to 65.... floored it (no kickdown) and it was OK until about 80 when it began to ping again. Temp gauge was 85% of the way to the top (stock gauge).

    Get home... let the car sit.

    Next day, I come out to oil all over my garage. At least 1/2 a quart. Top of the engine is dry... PCV was 1/2 out of the grommet. Both valve covers and exhaust manifolds were wet, top of the transmission and water pump were wet, breather foam was soaked.

    Topped off the oil and ran it. Starts and runs fine.

    Did my intake seals let go? Could this be caused by excessive blow-by from bad head gaskets or worn rings?

    I run high-zinc oil 10w40 Valvoline.

    Should I do a compression test first and then sort out getting a gasket kit and go to town replacing everything?

    So bummed out.
     
  2. beerbelly

    beerbelly In Maximum Overdrive SILVER MEMBER

    Messages:
    3,045
    Location:
    Portland OR
    Sorry to hear it. It sounds like excessive oil pressure is blowing out anywhere it can, but I don't know the exact cause. A PCV valve should allow a slight vacuum inside the engine, so I wonder if the PCV valve is not working? I do know that timing for a stock '65 289 is 6˚ BTDC, so your 12˚ is likely the cause of pinging.
     
  3. Hillbilly

    Hillbilly In Maximum Overdrive

    Messages:
    6,058
    Location:
    Winchester, TN.
    Do the compression check. Also make sure the pcv valve is getting engine vacume from the intake. May have to clean out those passages. Third, pull the valve covers and make sure the oil drain holes at each end of both heads are not plugged with bits of valve stem seals and built up gunk . Check for worn rings by warming up the engine then pull the pcv valve completely out of the valve cover to see if you have a small cloud of oil vapor coming out of the engine at idle. A cloud of vapor indicates that the rings are about gone and a rebuild is due. Don't forget to check that the pcv system can get clean air from the other valve cover.
     
    The Wrench, AimlessMoto and LSChero like this.
  4. LSChero

    LSChero In Maximum Overdrive PLATINUM MEMBER

    Messages:
    2,301
    Location:
    Area 6 NV
    Pull valve covers and watch valve movement when doing comp.test.May have flat cam.
     
  5. 65restomod

    65restomod In Overdrive BRONZE MEMBER

    Messages:
    817
    Location:
    Danville,VT left NJ forever
    pinging can also be caused by engine sucking in excessive oil, But you will know it by the smoke trail
    (Have you ever over filled a crankcase?) or added double the oil . Just quoting from a "friend"
     
  6. AimlessMoto

    AimlessMoto In Overdrive

    Messages:
    534
    Location:
    Townsend, MA
    Way too much power for a flat cam. The thing rips!
     
  7. AimlessMoto

    AimlessMoto In Overdrive

    Messages:
    534
    Location:
    Townsend, MA
    No smoke cloud behind the car... oil is smack on the "safe" level. AFR gauge O2 sensor isn't fouled.
     
  8. AimlessMoto

    AimlessMoto In Overdrive

    Messages:
    534
    Location:
    Townsend, MA
    I will give the engine and trans a good cleaning... clean the breather, and check the PVC valve.

    I will try the idle/PCV removal trick first.... then compression test with the valve covers off.

    Should find an answer somewhere in there.
     
  9. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

    Messages:
    11,463
    Location:
    Seguin, TX
    12 initial degrees is fine, more or less, but 34 total, at what RPM does that occur? I always check both centrifugal and centrifugal plus vacuum advance at 2500 RPM.
     
  10. pmrphil

    pmrphil In Maximum Overdrive GOLD MEMBER

    Messages:
    1,333
    Location:
    central CT
    Too much timing will make it ping, and THAT will cause pressure to build in the crankcase, quickly. Then the pressure exits at the point(s) of least resistance, valve covers, intake, front and rear seals, etc.
    There are little rubber "stop cushions" in the distributor that aid in limiting how much mechanical advance the distributor has, they are on the stop pins under the breaker plate. If you have an aftermarket distributor, it probably has too much advance.
    I second Andy's question, at what RPM does it achieve total advance? Many people check it at 3,000 RPM and don't bother to see if it still climbs after that. Most factory style (even replacement) distributors won't hit total advance until well after 4,000 RPM.
     
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  11. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

    Messages:
    11,463
    Location:
    Seguin, TX
    Of course, the truest way to check dizzy curve is on a distributor machine, but heck, hardly anyone has one.
     
  12. pmrphil

    pmrphil In Maximum Overdrive GOLD MEMBER

    Messages:
    1,333
    Location:
    central CT
    It's not so much the curve, but the total amount of advance, which you can check with a timing light.
     
  13. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

    Messages:
    11,463
    Location:
    Seguin, TX
    Right, but standing over a twirling fan, when the engine's at 4K, makes me nervous.
     
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  14. 65restomod

    65restomod In Overdrive BRONZE MEMBER

    Messages:
    817
    Location:
    Danville,VT left NJ forever
    If I remember right I thought there was a problem at one time with the flex fans shredding blades
     
  15. Hillbilly

    Hillbilly In Maximum Overdrive

    Messages:
    6,058
    Location:
    Winchester, TN.
    Better believe that about flex fans slinging blades. Never stand in line with one of those killers. I know ( Used to Know ) two local guys who got killed by flex fans exploding into pieces.
     
  16. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

    Messages:
    11,463
    Location:
    Seguin, TX
    Yup. My boss Randy forbade me from leaning over fans at any speed above idle, except when checking advance, and even then, only long enough for the reading.
     

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