Finally got a running 65 C10

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Ricko1966

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I bought an installed a new PCV valve, even though the old one rattles when you shake it. I removed both valve covers, sure enough both of them are leaking in the back lower part. That’s just crazy to me, because I literally had to pry these off with a pry bar. Permatex gasket sealant on both side sides.

What kind of crank case pressure could do this? Or is that even the issue? I just picked up the $75 fel pro blue with steel core. While I was at O’Reillys, I bought some of the steel chrome 4 inch long wing nut valve cover bolts, but of course the threaded part is not long enough now because the blue gasket is so thick. Wasted money. Need to go to the hardware store to get new bolts.

Also going to pick up that breather today, hopefully it has the draft tube with it
Draft tube and pcv systems are different. I don't think crank case pressure is your problem. I would put the valve covers on opposite sides from what you have now. Run a vent hose to the air cleaner like a factory pcv car. I also would set the valve covers on a glass table and look around the perimeter for any areas that are not touching the table. Most aftermarket air cleaners have a knockout for the vent hose,and used to come with the fitting. If you don't have 3 openings,I oil fill 1 vent,1 pcv you can buy an oil filler cap with a breather hose.
 

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1low4x4

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Draft tube and pcv systems are different. I don't think crank case pressure is your problem. I would put the valve covers on opposite sides from what you have now. Run a vent hose to the air cleaner like a factory pcv car. I also would seat the valve covers on a glass table and look around the perimeter for any areas that are not touching the table. Most aftermarket air cleaners have a knockout for the vent hose,and used to come with the fitting. If you don't have 3 openings,I oil fill 1 vent,1 pcv you can buy an oil filler cap with a breather hose.
So what’s the difference between a draft tube and a vent hose? If they both come off the valve cover and go to the air cleaner
 

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And something I just noticed, why is there a hole on the valve cover in that back corner? I’m away from the truck right now but when I get back I’m going to look at that

I don't like those valve covers at all. That hole has no reason to be there, other than to cause leaks. I also don't like that rough cast finish on the gasket surface.
 

1low4x4

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I don't like those valve covers at all. That hole has no reason to be there, other than to cause leaks. I also don't like that rough cast finish on the gasket surface.
Agreed yet when I say that on the 60s Facebook page, I’m bombarded with people who have had five different sets of them with no issues. Well, this is the second set I’ve ran and both have had issues. I’m going to order a new set, just a conventional set.
 

1low4x4

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Oreillys has these in stock 60 bucks. Going to see if I can find some spreaders too
 

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idahovette

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I personally would rather use the cast covers, they don't get out of shape if you get to zealous on tightening the bolts. Also you could JB weld the offending hole and then smooth it on both sides? IMO the "tin" covers need a lot of help to maintain no leaks.
 

Ricko1966

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So what’s the difference between a draft tube and a vent hose? If they both come off the valve cover and go to the air cleaner
Air rushing past a draft tube creates a vacuum drawing vapors out of the engine. Kinda like when a smoker cracks the window so the smoke gets drawn out of the car.
 

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1low4x4

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Just got home. Those aren’t holes, they’re indentations I guess from the casting process, that would happen to be filled with oil. Not really crazy about the idea of those irregularities on the mating surface either.
 

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DoubleDingo

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with the cork you'd think it would be fine. Smooth mating surface is definitely preferred, though
 

Ricko1966

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Another thing for you to consider. It is pretty normal for a valve cover vent like yours to drip on the valve cover. And I don’t know how tight your pcv grommet fits. What are the chances the oil is running across the tops of the valve covers,then down the back.
 

idahovette

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Those indentions are NOT causing the oil leak, they are minor. Unless the surfaces are not square, those covers shouldn't be the problem. The pcv system should be sucking enough to NOT allow the breathers to back flow......leak out? Are there baffles in the covers below the openings? OK went back and I see them
 

Ricko1966

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A piece of a sock and a rubber band will tell the tale if you are getting drips out of the breather.
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1low4x4

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I thought about the oil dripping down from the breather all the way to the back, but that would be a lot of oil. It’s possible though. A sock is a good idea, I was thinking red rag, but I don’t have any.

I went ahead and gave the original cast. Aluminum valve covers another chance, but with the new heavy duty blue fel pro gaskets. I already had some quarter 20 bolts, I just cut them down a little bit and used a nice thick washer. We will see. Onto the rear brake drum now.
 

1low4x4

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Brakes back together on that side, but no fluid. Someone before me changed all of the hardlines to brand new stainless, and the master cylinder. But they didn’t change the three rubber lines. I took the rear one out, suspecting it was closing in. Cut it open and it looks like it. Could be blocked at some point I don’t know. Honestly, I don’t know what the inside of one of these hoses is supposed to look like but this one looks awful small. Going to get another one tomorrow. The kid on the phone at O’Reillys started talking about 133 inch rubber lines so I just said look I’ll go to the main hub in town tomorrow and match it there don’t worry about it little buddy.
 

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