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Old 07-02-2020, 01:47 PM   #1
71CHEVYSHORTBED402
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Replacing valve covers, Flame Arrestor & Edlebrock Carbs

The gaskets on the oil caps for my C20 402 are toast. Could be one reason it runs through oil so fast Anyway, I'm not a fan of chrome and "it don't get you home". I have a pair of pre-71 BBC covers I can use. I'm pretty green where carbs & accessories are concerned.

This has an Edlebrock carb. and the manifold may be Edlebrock as well. My question is the original set-up had a flame arrestor, and I'm unaware of one with this Edlebrock. Perhaps they're unnecessary - the caps have a breather of some sort, I don't have a clue. If I don't need a flame arrestor with this, any suggestions how to plug up the hole in the valve cover where an arrestor would be? Edit: The chrome cap on the right is essentially a plug, with a breather or?

Any other considerations, or any reason these can't be used with the Edlebrock? Pics are of the current set up and what I hope are the replacement valve covers.
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71 Custom Deluxe, SWB, 2WD, 402, A/C. I developed an assm. guide "kit" for restoring it from ground up. With assys, the guide accts for 1000s details such as OEM identifications& part numbers, written in short order. 700+ images include assm, illust., charts, and points of interest. Much of the info. applies to all 67-72 GM trucks, and to a lessor degree all 67-72 GM vehicles. My build thread, and more on the guide https://67-72chevytrucks.com/vboard/...d.php?t=730025

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Old 07-02-2020, 02:48 PM   #2
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Re: Replacing valve covers, Flame Arrestor & Edlebrock Carbs

OK, so oil filler cap on one side, and a venting cap on the other? There is no flame arrester, I'm guessing, because I don't see a hose for filtered air going up to the air cleaner inside the air filter? If that is the case, the venting cap is probably full of some sort of really coarse "steel wool", which provides the arrest, and that is where the "clean" air for the PCV gets into the engine.
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Old 07-02-2020, 03:31 PM   #3
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Re: Replacing valve covers, Flame Arrestor & Edlebrock Carbs

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Originally Posted by Steeveedee View Post
OK, so oil filler cap on one side, and a venting cap on the other? There is no flame arrester, I'm guessing, because I don't see a hose for filtered air going up to the air cleaner inside the air filter? If that is the case, the venting cap is probably full of some sort of really coarse "steel wool", which provides the arrest, and that is where the "clean" air for the PCV gets into the engine.
Thanks Steve. Correct, the current set-up doesn't have a flame arrestor at the carb., for starts there's no carb. spacer for it. There are venting elements in both pieces, and they do appear to be steel wool.

If I'm reading you right, the caps are breathers and/or flame arresters. In other terms, can't use the old valve covers without one or both of these types of caps. Sound right?
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71 Custom Deluxe, SWB, 2WD, 402, A/C. I developed an assm. guide "kit" for restoring it from ground up. With assys, the guide accts for 1000s details such as OEM identifications& part numbers, written in short order. 700+ images include assm, illust., charts, and points of interest. Much of the info. applies to all 67-72 GM trucks, and to a lessor degree all 67-72 GM vehicles. My build thread, and more on the guide https://67-72chevytrucks.com/vboard/...d.php?t=730025
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Old 07-02-2020, 03:42 PM   #4
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Re: Replacing valve covers, Flame Arrestor & Edlebrock Carbs

If there is no other way to get filtered air, you are stuck with those caps. personally wouldn't do it that way because here in southern California we have a lot of dust and those can collect it and clog. A kit is made for the open air element air cleaners that allows for connection from the valve cover to the bottom flange. You would need an arrester on that, but it's just a steel mesh.
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Old 07-02-2020, 03:47 PM   #5
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Re: Replacing valve covers, Flame Arrestor & Edlebrock Carbs

You can get a valve cover breather that will twist in to the oil fill cap on your one orange valve cover. This will act as both a fill cap and breather. Then just plug the two taped over ports on the stock covers. You might use one of the taped over ports for a PCV set-up if your engine intake isn't already set-up for it. I can't tell from the photo if that line from the front of the carb is the PCV line and where it goes. I don't see why you could not use the orange covers.
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Old 07-02-2020, 08:14 PM   #6
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Re: Replacing valve covers, Flame Arrestor & Edlebrock Carbs

I ended up just getting a new breather cap for the LH cover, and a plain oil cap for the RH cover. I asked the 30+ NAPA guy about flame arresters and that, and he went Piffft.

Ran into an old guy afterwards. He's a blue color dude & drives a 68 Ford 428 1-ton. He says the regular cap is good, because the PCV valve on the RH side acts as an arrester as well. So unless I'm missing something, I'll save valve cover replacements for another day. Thanks for the help.
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71 Custom Deluxe, SWB, 2WD, 402, A/C. I developed an assm. guide "kit" for restoring it from ground up. With assys, the guide accts for 1000s details such as OEM identifications& part numbers, written in short order. 700+ images include assm, illust., charts, and points of interest. Much of the info. applies to all 67-72 GM trucks, and to a lessor degree all 67-72 GM vehicles. My build thread, and more on the guide https://67-72chevytrucks.com/vboard/...d.php?t=730025
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