btw i did a compression test, 120-130 psi. It has about 8.5 compression ratio
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62 Chevy II AF/X
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The baffle is in the valve cover, looks just like the baffles in the other dozen big block valve covers I have that all work fine.My fabulous web page
"If it don't go, chrome it!" --Stroker McGurk
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Originally posted by cantvalve16 View PostMaybe a breather to exhaust style evac would help(?)
I was almost to this point with my blown SBC for that very reason. The issue, though, was the intake manifold gasket wasn't sealing - thus allowing the blower to pressurize the case.... did you have any backfires when you were first getting it started?
one way to check this - are all the plugs similar in burn? sometimes you live an learn, in my case, I blew it up and learned - your spark plug on the offending hole should be showing signs of lean and pre-detonationLast edited by SuperBuickGuy; June 7, 2014, 01:43 PM.Doing it all wrong since 1966
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Originally posted by Deaf BobAll I can think of is bad ring, not flat head mounting surfaces..... Son's 455 Buick does seem to have a fair amount of blowby.. Old small blocks have the vent at the back of the block and a tube pointing down... Might not pass tech for you? .. Would love to know how you solve this, might solve the Buick's problem, if it is considered a problem.. Baffle fall out of the valve cover? Should be riveted in if al, spot welded if tin...Doing it all wrong since 1966
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Originally posted by SuperBuickGuy View Post
I was almost to this point with my blown SBC for that very reason. The issue, though, was the intake manifold gasket wasn't sealing - thus allowing the blower to pressurize the case.... did you have any backfires when you were first getting it started?
one way to check this - are all the plugs similar in burn? sometimes you live an learn, in my case, I blew it up and learned - your spark plug on the offending hole should be showing signs of lean and pre-detonation
My fabulous web page
"If it don't go, chrome it!" --Stroker McGurk
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What about the oil pan or timing cover? I would rather not drill the block.
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Originally posted by squirrel View Post
I thought of this, and it's possible that it's the problem. But the plugs all look identical. It did sneeze a couple times over the past couple weeks. But the idle doesn't act like it has a vacuum leak. I could pull the blower and intake and take a look....
mine ran perfect at idle, but it'd lean out under load and pingDoing it all wrong since 1966
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I haven't heard any pinging, but it's hard to hear much in the car...it's loud!My fabulous web page
"If it don't go, chrome it!" --Stroker McGurk
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I had to increase my crankcase volume to cure my WOT oil problems. This sure sounds like a bad sealing scenario though.
Maybe the rail seal just hasn't completely failed yet? Make several more "test passes" to try to get a full failure so you can pinpoint it?
Could the low boost be covering for a vacuum leak at idle?Of all the paths you take in life - make sure a few of them are dirt.
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Jim - have you swapped PCV valves with the '55 - just a trouble shooting tactic to throw out there.
The idea of the blower pressurizing the crank case via a leaking intake seal under the intake is a good one.
Does the engine consume much oil? (probably hard to tell with only 200 miles on it)
Thinking back to my fuzzy remembrance of leak down tests - could you put a compressed air fitting on an old spark plug as you would to hold up valves when changing springs, then use a regulator on the air line to decrease pressure to something reasonable to pressurize the cylinder, and through ring leakage - pressurize the entire crankcase - then search for air leaks? - any open valves will let air leak into intake and exhaust - so you'd have to back off all the rockers to close all the valves - probably more trouble than it's worth.
The car looks fantastic! LOVE LOVE LOVE the wheels!Last edited by milner351; June 9, 2014, 09:30 AM.There's always something new to learn.
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Thanks! the wheels are changing...
I have a leakdown tester, although it's part of my huge 1970s Sun tune up machine. I'm guessing that a leakdown test won't tell much.
Haven't seen any blue smoke out the tailpipe.
My fabulous web page
"If it don't go, chrome it!" --Stroker McGurk
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I finally finished the windows. Took way longer than it should, just getting up the motivation to work on it. I'm getting tired....My fabulous web page
"If it don't go, chrome it!" --Stroker McGurk
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