1978 308 GTS Oil Pressure dropping! | FerrariChat

1978 308 GTS Oil Pressure dropping!

Discussion in '308/328' started by PreppyRockrChick, Aug 15, 2018.

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  1. PreppyRockrChick

    Jan 22, 2018
    18
    WNY
    Full Name:
    Jules
    So, I have been tooling around, enjoying the Summer weather here with no issues. Now, suddenly, my oil pressure is dropping WAY down while I am driving. The first time it happened, I checked oil and put in 3 quarts. It is doing it again! Checked the dipstick and its like halfway between full and not, i don't want to overfill it...........Anyone have any idea what could be going on? I keep cardboard under the car to log drips. It's not dripping oil much.....
     
  2. Portofino

    Portofino Formula Junior

    Sep 17, 2011
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    Yorkshire UK / Switzerland/ Liguria ( Italy )
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    Portofino
  3. thorn

    thorn F1 Rookie
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    Aug 7, 2012
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    You say the first time it happened, you put in 3 quarts. Why? What I mean is, how did you decide that 3 quarts was the amount needed to add?
     
  4. PreppyRockrChick

    Jan 22, 2018
    18
    WNY
    Full Name:
    Jules
    After this happened I checked oil, it was VERY low. I added it one quart at a time and kept measuring til it came up. And the gauge still shows it dropping...weird
     
  5. mike996

    mike996 F1 Veteran

    Jun 14, 2008
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    #5 mike996, Aug 17, 2018
    Last edited: Aug 17, 2018
    First thing I'd do, after ensuring oil level is OK, is attach an external mechanical gauge and check pressure. The problem you are having could easily be an electrical issue with the gauge/sender.

    It's very unlikely to be related to the oiling system itself. An oil pump can't really exhibit that sort of behavior. Does it occur at totally random times or in certain maneuvers (hard left/right cornering), hard braking, etc?

    There are several, other possibilities, but the usual suspect would be a gauge/sender issue. I suppose there could be some sort of issue with the oil pickup in the sump - pinhole that is exposed to air when the oil level drops a bit, etc. But, again, that sort of thing is very rare.
     
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  6. NW328GTS

    NW328GTS Formula 3

    Nov 16, 2009
    2,191
    Washington
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    Hal
    I will say that my oil pressure dropped as my FRAM oil filter fell apart internally. There used to be a bunch of thread on how crappy they were. I went to Baldwin filters for my 328.

    Secondly... If you are losing oil but not finding puddles, and 3 quarts would make a very large puddle... Check your coolant for traces of oil. Do you have oil smoke on startup? its going somewhere.

    Also make sure you check the oil after the car has sat for 5-10 minutes. It will appear low if you check it right after shutoff. It takes a few minutes for all the oil to drain back to the oil sump. Checking it too soon can lead to overfilling.

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  7. Brian A

    Brian A F1 Rookie

    Dec 21, 2012
    3,079
    SanFrancisco BayArea
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    1983 US 308 GTS QV
    Is being low 3 or 4 quarts enough to cause oil starvation in a 308?

    Needless to say, loss of oil pressure is very serious stuff. Yeah, it might just be the gauge, which is harmless, but it might also be real.

    OP: Is the low oil pressure light also coming on or is it only the gauge that is showing low pressure?
     
  8. Lawrence Coppari

    Lawrence Coppari Formula 3

    Apr 29, 2002
    2,149
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    Years ago I had an oil pressure drop. It turned out that my Fram oil filter was crushed internally. Since then it's been all Baldwin oil filters and no more crushed oil filters and no oil pressure drops.
     
  9. Albert-LP

    Albert-LP F1 Veteran
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    Sep 1, 2010
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    maybe better doing an engine compression test: If the compression test is ok then the problem was just an oil filter internal failure.

    but first of all open the water nourice and check if there is oil mixed with water in the cooling system

    ciao
     
  10. thorn

    thorn F1 Rookie
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    Aug 7, 2012
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    I don't see how a compression test will indicate an oil leak, except in the valves and down cylinder walls themselves ... certainly there are tons of other areas oil to be troublesome. Could you elaborate? I'm always interested in learning more. :)
     
  11. miketuason

    miketuason F1 World Champ
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    Feb 24, 2006
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    If the inner shift shaft Seal is bad, it could be that some of the engine oil has gone over to the gearbox. The problem with the 308 transmission is that there’s no deep stick to check the gear oil level, I’m just saying, you might want to check this.
     
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  12. thorn

    thorn F1 Rookie
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    Aug 7, 2012
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    Depending on how long it's been since the gear oil was changed, it might be worthwhile to just go ahead and drain it, look at the fluid, and replace it. it's a fairly easy job if you can get the car off the ground high enough to get clearance for a ratchet and the drain pan.
     
  13. Albert-LP

    Albert-LP F1 Veteran
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    usually a big oil consumption means a big play between pistons and slivers and/or between the valves stems and the valve guides so the oil will be burnt in the combustion chambers in big quantities. All those two problems will be seen through a compression test
     
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  14. waymar

    waymar Formula 3

    Sep 2, 2008
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    Wayne Martin
    Did anyone say how many miles for the 3qts to be consumed? Was there very much hard down shifting? Or down hill in gear engine breaking? Very light oil on hot days etc. Just saying everything is relative.
     
  15. mike996

    mike996 F1 Veteran

    Jun 14, 2008
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    I think I misunderstood the original post. I was assuming that the problem was that oil pressure was dropping while the car was being driven but then would come back up at random. But it sounds like that is not the case.

    So, is the oil pressure dropping and goes back up AFTER you add more oil. Or does the pressure randomly drop/rise? My assumption was based on the latter which would usually be a gauge issue. But if there is insufficient oil in the sump, pressure will drop (or disappear) until more oil is added. If that's what's happening, as others have noted, the oil has to be going SOMEWHERE. If a fair bit of oil is going into the combustion chamber, I would expect considerable oil smoke to be visible...
     
  16. Albert-LP

    Albert-LP F1 Veteran
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    If the oil goes in the gearbox, at some time it will be filled and won't drink anymore oil and shifting would be very hard too.

    If the oil level is still dropping after you refilled with 3+3 quarts, I would say the engine is eating oil or at least there is a big leak somewhere.

    I would ask a friend to follow my car with his one while I'm driving it to look if there is smoke or burnt oil smell from my car

    ciao
     
  17. Albert-LP

    Albert-LP F1 Veteran
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    a ton of miles: 10K or more or less three years of standard usage for this kind of vintage cars (some shows, no racing, not many miles and so on), no less

    ciao
     
  18. waymar

    waymar Formula 3

    Sep 2, 2008
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    3qts for 10k miles is not an eye opener. Just saying.
     
  19. Steve King

    Steve King F1 Rookie

    Feb 15, 2001
    4,367
    NY
    I had a different problem with high oil pressure which was the pressure relief valve sticking. But at the time I also installed a back up gauge to verify my electrical sender was working. Pic below. Image Unavailable, Please Login
     
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  20. waymar

    waymar Formula 3

    Sep 2, 2008
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    Just for the record, was the electric guage accurate?
     

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