Fuel pump sprays oil...

Discussion in 'Ranchero Tech Help' started by neil brown, Apr 25, 2020.

  1. neil brown

    neil brown In Second Gear

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    My truck is 65 170 6 cylinder. When I got it, the fuel pump was leaking engine oil, so I replace it, but now the new one’s doing the same, seems to be from a little vent hole, but it makes a bad mess, why is it doing this? Thinking about deleting the mechanical pump and going electric, but I’d like to keep it stock and simple. Any ideas?
     
  2. 65restomod

    65restomod In Overdrive BRONZE MEMBER

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  3. TestDummy

    TestDummy In Maximum Overdrive SILVER MEMBER

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    The little weep hole usually leaks gas when the pump diaphragm goes bad (a perfect way to tell when it does). I have never seen oil come out of one. Pics?
     
  4. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    I have, but only a couple times. But, is it installed with a gasket? I'd at least verify it's not a problem with the gasket or block.
     
  5. neil brown

    neil brown In Second Gear

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    Oil and filter changed in the last week, 4qrts went in, dipstick level looks good. New gasket fitted with the new pump about 6 months ago, but the old pump was doing the same. In the pic, you may be able to see how shiny/wet the gaskets in the pump are. I wondered if it’s exsesive crank pressure for some reason, but it’s got the stock breather, road draft tube etc.
     

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  6. grebaba

    grebaba In Fourth Gear

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    It doesn't look like it is leaking from the weep hole. I don't see any oil coming out of it.
    I think it is coming from the gasket between the two cases.
    With everything being rebuilt in china now the quality of the gaskets are about non existent.
    You might try to tighten the screws holding the case together. Not to tight but enough to get a good seal.
    Greg
     
  7. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    And, if you can do so, fit it with a PCV valve and air intake to the valve cover from the air cleaner. That's one of the jobs of the PCV, it reduces crankcase pressure.
     
  8. 65restomod

    65restomod In Overdrive BRONZE MEMBER

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    But if it has a road draft tube , Isn't that supposed to relieve pressure? PCV probably goes where the oil lube pipe is in the valve cover
    I, to think that it might be worth tightening all the screws.
    What about oil creeping out of the fuel pump hold down screws? Put a little sealer on them maybe?
     
    Last edited: Apr 26, 2020
  9. pmrphil

    pmrphil In Maximum Overdrive GOLD MEMBER

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    The "gasket" visible in the pic is the diaphragm, unless it's loose, nothing will go past it. If it's ruptured, FUEL will go past it !! Try removing the pump, cleaning out the cavity (spray bomb) and then fill the cavity with grease. It will stop oil from splashing around.
     
  10. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    Hmmm, nice trick. I'll have to remember that.
     
  11. 1979 RANCHERO GT

    1979 RANCHERO GT In Maximum Overdrive

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    On my 57 312 the road draft tube has a screen filter canister at the top of it, is that plugged so it wont vent? Often overlooked.
     
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  12. neil brown

    neil brown In Second Gear

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    My road draft seems to come straight out of the head as a pipe, then down the front of the block.
    I have a pipe from the breather/filler on the valve cover to the air filter.
    Here’s a pic from today’s little journey to work. This pipe and pump were clean when I left home. You can see lots of small droplets on the flexi fuel line to the pump, and the oil sprayed on the inner fender well next to it.
     

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  13. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    Unfortunately, that's what a draft tube will do, especially if there's excessive blow-by. Replacing the draft tube with a PCV in the valve cover, and installing a filter on the end of the tube, effectively making it a fresh-air intake, will go a long way in controlling the oil loss. It likely won't fully stop it, but at least it'll be in much better control.
     
  14. pmrphil

    pmrphil In Maximum Overdrive GOLD MEMBER

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    If you can, remove the draft tube and make certain it's not plugged up, and check the port in the head at the same time. The only way it would lose that much would be a TON of crankcase pressure, normal blow-by should be taken care of by the draft tube.
     
  15. neil brown

    neil brown In Second Gear

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    So do you think thats all coming out of the draft tube? How would I convert that to a pcv? Is there a kit? (I know they're available for some engines)
    I do have an 'open' tube at the top of my carb with nothing attached, could I use that? Do you just remove the draft tube, then run a hose from the 'hole' to the carb?
     
  16. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    The 'open' port has to have manifold vacuum and be 1/4" (6.5mm) in diameter to work. Can you provide photos of your carb, carb mount and intake (somewhat close-up) so we can familiarize ourselves with your intake? Of course, air cleaner off.
     
  17. neil brown

    neil brown In Second Gear

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    Here you go Andy, the press ‘tube’ on the top of the darn casting, but also found this bung in the base plate.
    Intake only has one port, which is being used for the trans vacuum
     

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  18. Kris S.

    Kris S. In Second Gear

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    That oil leak, I feel you there. Took my car to the shop for a small main leak. Now the area where timing plate meets oil pan has a major leak. It's under warranty but really starting to distrust the shop.

    You could do a block off plate and electric fuel pump if you decide to go that route. I'm going to leave the troubleshootin' to the more advanced crowd here. They are really good at that! :D
     
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  19. neil brown

    neil brown In Second Gear

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    I was thinking that, be really simple, apart from getting power to the pump. If it’s the road draft tho, changing that out will eliminate the problem, I’d much rather keep the mechanical pump
     
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  20. Kris S.

    Kris S. In Second Gear

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    Completely understand.
     

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