Venting questions and more

JohnFC196

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Hi, I have a built 196cc clone. Its a mod2 cam, billet rod and PVL flywheel, champion rockers and head is shaved. I noticed a lot of oil coming out of my stock breather before I switched over to champion rockers, and I want to do some venting. I originally thought maybe my head gasket wasn't sealing, because it was a decent amount of oil, but I took the head off and everything seems fine (no marks from combustion or any leaks)

I am going to be buying a champion valve cover, the one that has more clearance for the rockers. As I said, I want to do some venting to my engine, but I'm not sure how to go about it.

If I drill and tap the valve cover, will there be enough material for me to screw the fitting in tight? Should I use Teflon tape or high heat epoxy on them?
If the valve cover already has a one way valve in it, can I use that for my crankcase vent to a catch can and just run the lines from the valve cover straight to the engine side cover?
 

Rat

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Hi, I have a built 196cc clone. Its a mod2 cam, billet rod and PVL flywheel, champion rockers and head is shaved. I noticed a lot of oil coming out of my stock breather before I switched over to champion rockers, and I want to do some venting. I originally thought maybe my head gasket wasn't sealing, because it was a decent amount of oil, but I took the head off and everything seems fine (no marks from combustion or any leaks)

I am going to be buying a champion valve cover, the one that has more clearance for the rockers. As I said, I want to do some venting to my engine, but I'm not sure how to go about it.

If I drill and tap the valve cover, will there be enough material for me to screw the fitting in tight? Should I use Teflon tape or high heat epoxy on them?
If the valve cover already has a one way valve in it, can I use that for my crankcase vent to a catch can and just run the lines from the valve cover straight to the engine side cover?
Assuming you have the very common stamped tin rocker cover, you're not threading that and getting it to hold, the tin just isn't strong enough.

I'm using Champion rockers (old style) in my 208 and noticed it flings more oil around, but my head didn't have the overhead clearance for the reed valve insert... removing it lead to hemorrhaging oil through the breather. Me being me cut the insert flanges off so I could force it in farther and clear the rockers. I drilled holes through the corners to tack welded it in place and effectively solved the problem and Im vented to atmosphere.

Venting is required, all engines have some form of positive crankcase vent. If you want to gravity separate the oil into a catch can run it downward and stick a Y fitting in it. With a pair of check valves (low pressure not PCV) on one of the upper 2 branches leading to a filter and the bottom single to your catch. The reed flapper in the most valve cover is mostly to block oil splatter from exiting, but is progressively worthless the when you get into higher rpms because the it just wants to stay open.

This configuration will effectively act similar to the 45° traps on plumbing that prevent backflow... for your purpose it will allow the oil down, but not out As well as maintain some degree of semi-constant vaccum in the crankcase which is what you want.

If your engine side cover has the dual fill ports, you can shave the cap below the cylinder head flat and stick a barb fitting in it and just trickle the oil directly back into the block, which with everything else the same as I've stated will be easier to configure and tuck out of the way.
 

BrownStainRacing

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Hi, I have a built 196cc clone. Its a mod2 cam, billet rod and PVL flywheel, champion rockers and head is shaved. I noticed a lot of oil coming out of my stock breather before I switched over to champion rockers, and I want to do some venting. I originally thought maybe my head gasket wasn't sealing, because it was a decent amount of oil, but I took the head off and everything seems fine (no marks from combustion or any leaks)

I am going to be buying a champion valve cover, the one that has more clearance for the rockers. As I said, I want to do some venting to my engine, but I'm not sure how to go about it.

If I drill and tap the valve cover, will there be enough material for me to screw the fitting in tight? Should I use Teflon tape or high heat epoxy on them?
If the valve cover already has a one way valve in it, can I use that for my crankcase vent to a catch can and just run the lines from the valve cover straight to the engine side cover?
I tap the stock valve cover. No leaks, no problems.

Mines got over 100 hrs, my son's got over 200 hrs on his.

I use 2) 1/2" one way check valves to control crankcase pressure. With the stock pcv and plate removed.
Keep em up and away from the valve cover, and you won't have anymore oil blowing out.

The stock pcv dont work well at 5000+ rpm. You can see for yourself with a vacuum/pressure gauge.

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Hellion

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I tap the stock valve cover. No leaks, no problems.

Mines got over 100 hrs, my son's got over 200 hrs on his.

I use 2) 1/2" one way check valves to control crankcase pressure. With the stock pcv and plate removed.
Keep em up and away from the valve cover, and you won't have anymore oil blowing out.

The stock pcv dont work well at 5000+ rpm. You can see for yourself with a vacuum/pressure gauge.

Is the cover in photo #1 a cast aluminum valve cover? Much easier to tap if so. But for a stamped steel cover, a thin nut and washer on the inside could keep the vent fitting secure and from working loose.

Do you have any nuts in use on the inside of the cover or any Loc-tite?
 

Rat

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Is the cover in photo #1 a cast aluminum valve cover? Much easier to tap if so. But for a stamped steel cover, a thin nut and washer on the inside could keep the vent fitting secure and from working loose.

Do you have any nuts in use on the inside of the cover or any Loc-tite?
Oh yeah Real thin, like 1/4" hight max in whatever thread size. I didn't like the idea much myself but I considered suggesting it.

I'd rather take a micro bit and pop a few holes around the hole and tack weld the nut in place going that route, but that tin is fairly easy to burn up if you aren't at least well practiced and anticipating it... thankfully tacking through a hole for a heavier metal acts enough as a heat sink that it's easier
 

JohnFC196

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Oh yeah Real thin, like 1/4" hight max in whatever thread size. I didn't like the idea much myself but I considered suggesting it.

I'd rather take a micro bit and pop a few holes around the hole and tack weld the nut in place going that route, but that tin is fairly easy to burn up if you aren't at least well practiced and anticipating it... thankfully tacking through a hole for a heavier metal acts enough as a heat sink that it's easier
I don't have a welder, its been a while since i've welded otherwise. Anyways, I'll get a spacer to tap instead because it seems easier. What should I use to seal the threads on the side cover after im done tapping it? Im assuming teflon tape would not work for oil or high heat. Should I use O-Rings or just RTV as a thread sealant? Thanks again
 

BrownStainRacing

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Is the cover in photo #1 a cast aluminum valve cover? Much easier to tap if so. But for a stamped steel cover, a thin nut and washer on the inside could keep the vent fitting secure and from working loose.

Do you have any nuts in use on the inside of the cover or any Loc-tite?
No, jus stock tin. Both engines have the same cover.

I did experiment with the aluminum barb fitting to see it it would hold, it holds, no leaks.

I don't recommend any permatex, it came loose and showed up on the inside.

Teflon tape would be a good idea, but I see no leaks....so far.

No nut, washer, or lok-tite on the inside.. it's ez, no brain surgery or over complicated bs involved.

I rode em both today. I didn't look closely, but the shop floor will let me know if they still seal, 😆 😂 🤣 .
I'm sure there will be no spots on the floor in the morning, havnt seen any yet, and I don't own garage queens.

I thought about a nut on the inside, but it holds so I see no need in it.

The tap I used is NPT, jus tap it enough to get the barb started and she'll tighten right up for you.

I gotta do another cover for the Ducar 224. I can get pics if you need em.

@JohnFC196 I don't mean to hi jack your thread. I'm backing out.

Good luck, 👍
 

Rat

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The tap I used is NPT, jus tap it enough to get the barb started and she'll tighten right up for you.
That's something I haven't tried yet 🤔 NPT being tapered/conical is essentially self sealing and self binding so unless you go full blown gorilla ans strip it, NPT doesn't vibrate itself loose or leak... no additional anything needed generally.
 
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