Ventilation Regulator Valve... oil leak?

Discussion in 'Ranchero Tech Help' started by toddrichert, Aug 20, 2021.

  1. toddrichert

    toddrichert In Second Gear

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    If I'm interpreting my shop manual correctly, the green tube here is attached to a Positive Crankcase Ventilation Regulator Valve:

    valve.jpg

    This valve and I have something in common in that, before today, neither of us knew each others' names!

    As you can probably see in the photo, I have what appears to be fresh oil leakage on the side of my 144 here. When I wipe it off then the fresh shiny stuff reappears during my next drive. This little elbow joint (valve?) with the green tube attached (right between my water pump and distributor cap) is positioned just north of where the most prominent area of fresh leakage seems to be recurring.

    I looked to the shop manual to find out what this thing is, does, and what on earth flows through it. I'd presumed either oil or coolant until the shop manual indicated "air."

    Does air flowing through the crankcase carry enough oil residual to cause oil leakage from a connection like this? Is this normal?

    I've already replaced my valve cover gasket, including reflattening the valve cover perimeter where it was previously overtightened. I think I've got a decent seal there now.

    At this point I'm not seeing any significant leakage north of this regulator valve connection, but it seems weird that an air flow valve should be leaking oil. But is that what's actually happening here? Am I missing something?
     
  2. pmrphil

    pmrphil In Maximum Overdrive GOLD MEMBER

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    It is air, but it's air from within the engine, which contains fumes (that are "heavy" with oil) from blowby in the engine. Some of the combustion in the cylinder(s) gets pushed past the piston rings and creates pressure in the crankcase that is relieved by the elbow and hose. Try and remove the elbow and seal up the sides with some type of sealant, preferably something non-hardening, maybe permatex #2?
     
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  3. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    Is the elbow only inserted, with no seal/o-ring? It would be logical if it had an o-ring.
     
  4. pmrphil

    pmrphil In Maximum Overdrive GOLD MEMBER

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    Gotta remember the year, Andy. Seals or O-rings weren't widely used then, much less PCV valves. Engines used road draft tubes instead.
     
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  5. toddrichert

    toddrichert In Second Gear

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    Well I didn't even get to the elbow... the first logical step was to remove that green tubing from the elbow, but when I started to loosen the hose clamp it seemed to me that it was unscrewing a little too easily. The question popped into my head "is this hose clamp already a little bit loose?" which auto-triggered another question "it's not going to be really that simple, is it?"

    But it seemed unwise to proceed with the elbow removal until I had ruled out the easier solution of a loose hose connection first. Soooo... I tightened up that hose clamp and I've been on a couple short drives since then. Pleased to report that there is no sign of new seepage yet!

    If that changes I'll get the elbow off and see what I find, but for now I'll just keep an eye on it for awhile longer.
     
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  6. toddrichert

    toddrichert In Second Gear

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    OK the seepage is definitely back. Except, how do I get this elbow to turn? I pulled the hose off and now I'm stuck.

    It's like a smooth round surface, and when I put even the lightest pressure on the bib sticking out, it started bending like aluminum. You can see where it started to flatten on the edge when I tried to leverage it:

    vent regulator valve.jpg

    And if I put a decent grip on the larger body of the valve, with some locking pliers for example, it would most definitely deform the unit... feels like very soft metal.

    Maybe this is one I should just take to the mechanic and let it be his problem to solve. Although I'd rather do a repair myself but I just don't want to break anything. Any ideas?
     
  7. beerbelly

    beerbelly In Maximum Overdrive SILVER MEMBER

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    My guess is that's a road draft tube conversion to PCV- does the green hose continue up to the valve cover? I think that your elbow may be a home-brewed press fit with some Permatex sealant around it. Here's a photo of a stock 144 with a factory road draft tube in the same location- it's literally a tube that empties crankcase gas & oil fumes into the atmosphere under the car.

    received_2383798628550261-630x390.jpeg
     
    Last edited: Sep 6, 2021
  8. pmrphil

    pmrphil In Maximum Overdrive GOLD MEMBER

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    When I went back and looked at the your first photo, the hose clamp had oily buildup on it, ABOVE the end of the hose. That tells me that there is leakage above the hose. I'd recommend cleaning the area WELL (dry?) and watch for where it starts first. I wouldn't mess with the elbow just yet.
     
  9. toddrichert

    toddrichert In Second Gear

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    Very good advice; I will do more in-depth sleuthing on the leak source(s) because I could be missing the real problem, and worse, maybe cause a new one...
     
  10. toddrichert

    toddrichert In Second Gear

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    No, it goes around the valve cover and seems to hook up at the base of the carburetor... the device I'm on now won't let me post a photo but when I get home to my real computer I'll upload pics
     
  11. toddrichert

    toddrichert In Second Gear

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    Here's the path for that green hose:

    green tube 1.jpg

    ... and a view from the passenger side:

    green tube 2.jpg
     
  12. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    At this point, I have to ask: is there a PCV valve somewhere between the two ends of the green hose?o_O
     
  13. toddrichert

    toddrichert In Second Gear

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    I don't see anything between the 2 ends of the green hose, except only more green hose...
     
  14. beerbelly

    beerbelly In Maximum Overdrive SILVER MEMBER

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    I believe what you have is similar to this setup, except you don't have the brass fitting- that's for plumbing into a V8 intake manifold. I've read that earlier 144 engines had the road draft tube, and others had this system. If the green hose is old & brittle, it would be easy to replace and may fix your issue, and the PCV valve is still available if you'd like to replace it.

    Screen Shot 2021-09-11 at 1.28.25 PM.png green tube 2.jpg

    I also think PMRPhil is right; oil could be seeping from the valve cover directly above, another easy fix.
     
  15. pmrphil

    pmrphil In Maximum Overdrive GOLD MEMBER

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    I see in the picture above the PCV valve with the green hose attached. I also see oil residue at that end. My question is: does the green hose fit tightly on each end? The solution may be so simple as finding a hose that fits very tight (probably causing a fight to get it on :mad:) to cure the seepage at both ends.
     
  16. Hillbilly

    Hillbilly In Maximum Overdrive

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    Those old style horizontal PCV valves greatly benefited from a periodic cleaning. Also make sure the hole it screws into is clean, got to have intake vacume for the PCV to function. A tight fitting hose helps too.
     
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  17. toddrichert

    toddrichert In Second Gear

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    Finally got around to replacing that green hose today. Those of you who speculated that it wasn't sealing well at the ends, were probably correct. That green tube was *severely* hardened from age!

    My shocks and other parts are supposed to arrive over the next 2 days and I hope to have her driving again by the end of the week (work schedule permitting.) Once I get her back on the road then I can begin to reassess for where my leaks are coming from...
     

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