312 burning oil and gas on dipstick
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Car: 91 ws6
Engine: Carb'd 334 stroker
Transmission: T5
312 burning oil and gas on dipstick
howdy, I have a t/a with a 305, originally a tpi and now straight carb.
eddy rpm and holley 600 vac sec, no choke.
Stock heads, vac advanced dizzy.
After the carb conversion, she burns a little oil.
There's also a slight smell of gas on the dipstick and in the pan.
I've changed the oil since. Otherwise she runs and idles fine, though blows fire out the left side header on WOT.
The pcv hoses aren't hooked to the air cleaner, and its definitely oil. Not much is being burned.
motor has 36k original miles, bored .40 over.
Could that be bad rings? Valve guides? or the carb adjusted wrong?
eddy rpm and holley 600 vac sec, no choke.
Stock heads, vac advanced dizzy.
After the carb conversion, she burns a little oil.
There's also a slight smell of gas on the dipstick and in the pan.
I've changed the oil since. Otherwise she runs and idles fine, though blows fire out the left side header on WOT.
The pcv hoses aren't hooked to the air cleaner, and its definitely oil. Not much is being burned.
motor has 36k original miles, bored .40 over.
Could that be bad rings? Valve guides? or the carb adjusted wrong?
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Car: 91 ws6
Engine: Carb'd 334 stroker
Transmission: T5
Re: 312 burning oil and gas on dipstick
Nothing, but the original pump was pulled and replaced with a filter, with a new one installed in the engine bay putting out 6 psi.
the mods I've done are eddy intake, holley carb, accel vacuum advance dizzy, SBC headers flipped, carb fuel pump, fel pro gaskets, and ford plug wires.
She has no problem running, and actually wasn't getting enough fuel till I adjusted the floats. No vacuum leaks either, and she didn't burn anything whilst the tpi was still installed
the mods I've done are eddy intake, holley carb, accel vacuum advance dizzy, SBC headers flipped, carb fuel pump, fel pro gaskets, and ford plug wires.
She has no problem running, and actually wasn't getting enough fuel till I adjusted the floats. No vacuum leaks either, and she didn't burn anything whilst the tpi was still installed
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Car: 91 ws6
Engine: Carb'd 334 stroker
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Re: 312 burning oil and gas on dipstick
$1500 build, computer was fried, injectors were fried, and half the harness was fried. Plus I like the simplicity of a carb
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Mechanical fuel pumps will put gas in the oil when there's a leak in the pump diaphragm.
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Specifics are always nice...
Have you verified fuel pressure at the carb?
Electric pumps work better close to the tank, but that isn't causing your gas-in-oil problem.
How did you set the ignition timing, and where do you have it set?
Have you verified fuel pressure at the carb?
Electric pumps work better close to the tank, but that isn't causing your gas-in-oil problem.
How did you set the ignition timing, and where do you have it set?
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Car: 91 ws6
Engine: Carb'd 334 stroker
Transmission: T5
Re: 312 burning oil and gas on dipstick
Yes, confirmed 6 psi at carb with two different gauges.
Ignition timing set via slowly rotate crank, stick screwdriver in #1 hole, repeat till its at tdc.
Can't say exactly how much since its tuned by ear, but I can rotate the dizzy an inch and a half ish either direction and it bogs. Right where I have it sounds the best and runs the best. Revvs up fine with no stumbling er backfire from carb, though my headers make nice flamethrowers at redline, regardless where I set timing.
(headers are shorties flipped upside down)
Ignition timing set via slowly rotate crank, stick screwdriver in #1 hole, repeat till its at tdc.
Can't say exactly how much since its tuned by ear, but I can rotate the dizzy an inch and a half ish either direction and it bogs. Right where I have it sounds the best and runs the best. Revvs up fine with no stumbling er backfire from carb, though my headers make nice flamethrowers at redline, regardless where I set timing.
(headers are shorties flipped upside down)
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From: Illinois
Car: 1989 Camaro Iroc Z
Engine: L98
Transmission: 700R4
Axle/Gears: 9 Bolt Borg Warner/ 2.77 gear
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Car: 91 ws6
Engine: Carb'd 334 stroker
Transmission: T5
Mostly she didn't burn oil before the intake swap.
Two bolts won't scree all the way in, one by cyl 7, the other in the middle other side. They only go half way down, could that be the cause? Oil leaking to the intake?
Two bolts won't scree all the way in, one by cyl 7, the other in the middle other side. They only go half way down, could that be the cause? Oil leaking to the intake?
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Car: 1991 firebird
Engine: TBI 305 (built)
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Is say more like gas leaking from intake into oil when engine is off or at idle and oil getting sucked into the intake when rpm's rise
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From: Henrietta NY
Car: 1984 Trans Am L69
Engine: Sniper EFI Powered 355
Transmission: WC T5 w/ Steel Support Plate
Axle/Gears: 3.42 10 Bolt Posi
Re: 312 burning oil and gas on dipstick
Take it apart and put it together correctly then report back
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Car: 91 ws6
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Theres always two that won't thread in all the way, no matter what I do. They're the original intake bolts as well, going back in the same hole they came out of.
Would it wreck anything by just leaving it and making sure I have enough oil?
Would it wreck anything by just leaving it and making sure I have enough oil?
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Joined: Oct 2004
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From: Henrietta NY
Car: 1984 Trans Am L69
Engine: Sniper EFI Powered 355
Transmission: WC T5 w/ Steel Support Plate
Axle/Gears: 3.42 10 Bolt Posi
Re: 312 burning oil and gas on dipstick
Are you using the correct intake? Some have slanted center holes I think 87 and up.
You need the correct carb intake or to oblong the holes.
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Car: 91 ws6
Engine: Carb'd 334 stroker
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It appears to be correct. I have an 85 block, no idea what the intake came from, it was a junkyard find. Every time I put it back on, its two different ones that won't thread all the way. Always one on each side though
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Joined: Oct 2004
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From: Henrietta NY
Car: 1984 Trans Am L69
Engine: Sniper EFI Powered 355
Transmission: WC T5 w/ Steel Support Plate
Axle/Gears: 3.42 10 Bolt Posi
Re: 312 burning oil and gas on dipstick
Inspect the bolts for damage as well.
What is the casting number on the heads?
Center bolt valve covers?
Last edited by midias; Dec 13, 2013 at 01:56 PM.
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Car: 91 ws6
Engine: Carb'd 334 stroker
Transmission: T5
Take it off, run a tap through all the head holes and slowly thread the bolts back in. Don't thread any one in all the way first do them all even. You may have to open the intake holes up a little first.
Inspect the bolts for damage as well.
What is the casting number on the heads?
Center bolt valve covers?
I haven't looked, they're factory for an 85 tpi though.
Negative, ghost rider
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From: Henrietta NY
Car: 1984 Trans Am L69
Engine: Sniper EFI Powered 355
Transmission: WC T5 w/ Steel Support Plate
Axle/Gears: 3.42 10 Bolt Posi
Re: 312 burning oil and gas on dipstick
Otherwise you may have to open the holes on the intake a bit. My block was decked and I had to do the same.
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Car: 91 ws6
Engine: Carb'd 334 stroker
Transmission: T5
Just fired her back up, noticing something else. It seems to be just the drivers side header, and it gets worse the longer she runs. Passenger side sounds fine and doesn't smoke at all. I noticed one bolt on my drivers side header somehow wiggled out as well
If a video would help I could take one
If a video would help I could take one
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Car: 91 ws6
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Its not much at first, and its not a steady stream. It comes in pulses, after running about 5 minutes the drivers header turns into a steam engine. Only its oil lol
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Car: 91 ws6
Engine: Carb'd 334 stroker
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Compression test shows 190 +/- 5, only a wee bit of oil on plugs 1 and 3, and it never fouls out. On the bolt on the intake drivers side I noticed it had a little oil on it, as well as a small amount puddled on the intake above it.
Starting to think Tis an intake gasket/intake not tight enough.
Starting to think Tis an intake gasket/intake not tight enough.
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From: Charlestown, IN
Car: 1971 Camaro
Engine: 427
Transmission: TKO600
Axle/Gears: 3.73
Re: 312 burning oil and gas on dipstick
Like others gave already said, replace the intake gaskets, tighten the bolts properly ( proper torque AND sequence) use sealer on the bolt threads.
Hook up the Pcv system and male sure thr other valve cover has a breather.
Header bolts often need retorquing.
Intake bolts will require retorquing after it has ran the first time.
Hook up the Pcv system and male sure thr other valve cover has a breather.
Header bolts often need retorquing.
Intake bolts will require retorquing after it has ran the first time.
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