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Discussion Starter · #1 ·
new cylinder heads, intake and carb here on the 383. blowing blue tint out of both sides of the exhaust. seems like the pcv is`nt working, for the hose is completely dry, going to the base of the carb, have plenty of vacuum i`m guessing crankcase fumes up the cylinders instead of out the pcv? any ideas would be appreciated. calling flo-tek today to see if maybe the heads were coated with something from the factory? i used the gaskets they said to use. i looked in the intake manifold with a scope. looks like the intake gasket has black spots on it,,,,,, fel-pro`s are blue. i`m thinking sucking oil in the bottom of the intake gaskets maybe? they went on dry. 175 compression on all 8. thanks, for any discussion would be greatly appreciated! pulling my hair out.
 

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new cylinder heads, intake and carb here on the 383. blowing blue tint out of both sides of the exhaust. seems like the pcv is`nt working, for the hose is completely dry, going to the base of the carb, have plenty of vacuum i`m guessing crankcase fumes up the cylinders instead of out the pcv? any ideas would be appreciated. calling flo-tek today to see if maybe the heads were coated with something from the factory? i used the gaskets they said to use. i looked in the intake manifold with a scope. looks like the intake gasket has black spots on it,,,,,, fel-pro`s are blue. i`m thinking sucking oil in the bottom of the intake gaskets maybe? they went on dry. 175 compression on all 8. thanks, for any discussion would be greatly appreciated! pulling my hair out.
Does the valve cover have a Pcv baffle.
 

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@Dave the Wave only way the pcv won't work is if the hose isn't hooked up or... The pcv itself is stuck shut and isn't allowing the vacuum to be pulled. Have you pulled the pcv out of the rocker cover while the engine is running and placed your thumb over the bottom of it? You should have vacuum enough to suck your thumb to the underside port from the valvetrain side of the pcv. If that functions as it should, my guess is a vacuum leak on the intake manifold gaskets.
 

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1969 Nova . . 2dr . . Chino Valley,Az USA
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Dave - - - - here's my question = ?

Your valve cover "baffel" - if you have u'r v/c 's off - take us a picture of those BAFFELs .

I'm using a M E Wagner - DF 17 pcv valve (yes - "the most expensive PCV Valve" ) , but works great . You can even go too their web-site ; they talk about : you need a V/C - PCV baffel.
And , general good reading .

We (here on SNS) , have done a few "Group Buys" , for these DF-17 PCV Valves , and saved afew dollars - - look here .


just some good info .

But, you should check u'r pcv valve , as Andy says - "check for vacuum leaks" .

Then, my V/C question = about your 'Baffel' . . you should check that also (like does u'r baffel - really block u'r pcv valve & deflect u'r oil . . ? ) .

Why I ask = I even installed an "oil catch can" - on my L 6 engine , and just checked that catch can. it seems too work really good - my engine (I've had my 69 , for over 25yrs - -
and have never 'over-hauled' my engine) = so, I expect a little oil usage. My "can" also helps my carb = that doesn't have too burn that (extra) oil, either.

let us know , what you find (feed-back) - please .


jim
 

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1969 Nova . . 2dr . . Chino Valley,Az USA
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My second question , for you - - - - does your engine "build any oil pan = pressure ; or does your oil dip stick = blow ' out of the dip stick tube ' - any . . ?

like do you have any - pressure in u'r oil pan ?

You say that -

yes, one cover with pcv baffled, one cover with a breather

this is good - - because your engine - - needs to "breathe" - -

just checking , and covering all those 'bases' .

thanks , jim


 

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This baffles me! :p In all seriousness, if you have a breather and the PCV, you shouldn't be getting much if any smoke from the tailpipes unless you're sucking oil into the combustion chamber.... Leading me to my initial thought of an intake leak, either gasket or bolt or both... What intake are you running? My guess is one or both of the center bolts beneath the carb riser are the culprits.

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As these are typically difficult to tighten on some manifolds, they tend to miss the boat on the correct tightness. I would avoid torquing them but rather, use gaskasinch on each side of the new gaskets, with the RTV along the China Walls then, use Permatex thread sealer (or other sealer, NOT rtv) on all your manifold bolts. The Flo-Tek heads have 4 through-drilled holes on each side from what I see and that leads each bolt to the lifter valley without sealing...

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Always a good idea to use sealant anyhow on ALL bolts for manifold sealing... Just to be safe for oil, vacuum and coolant!

Hope this helps.
 

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Discussion Starter · #9 ·
Holy response, Batman! Ok, BIG thanx you guys. Ok, I had this exact set up on my 355 in my ‘57, baffled Mickey Thompson covers, I made the baffles, worked excellent. I took these off before it went away As for oil dip stick, does not blow out. How can I tell otherwise if I have pressure in the crankcase? Have 17 vacuum at 1500 rpm sitting here in the garage. I’ll try to post pics. Sorry, I just don’t know how, understand how. I have the pcv going to the rear of the edelbrock. Tried it up front, same. I have all bolts with sealant on them.
 

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Well, you could take off the hose from the back of your Ede carb, cap the outlet and stick a balloon on the end of the hose to see if it pressurizes at all...

[EDIT] It shouldn't pressurize at all (or just very slightly) with the breather on your rocker cover... I typically use a crankcase evac system with check valves instead of a pcv so my crankcase always has negative pressure solely dependent on RPM as well as blow-by...

Pop these into my exhaust (AFTER the O2 sensors for EFI):
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Theory is the exhaust pulse creates a pressure waves to carry blow-by and evacuate the crankcase.
 

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Before you go off half-cocked you should try to determine the actual problem.

So you think you might be sucking oil into your carb from the PCV line? You say there is blue smoke out of the tail pipes?

Well then disconnect the PCV hose from the valve and plug it.

If you still have blue smoke out the tail pipes it wasn't the PCV hose (which is unlikely).

I'd be looking elsewhere.
 

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1969 Nova . . 2dr . . Chino Valley,Az USA
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I’ll try to post pics. Sorry, I just don’t know how, understand how.




" Dave " - - posting pictures = some instructions , below :

easy too do , here on SNS ;



I hope this helps ,

jim
 
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