Spraying Oil

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SudoDrag

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My 383 bored and stroked to 496 was pushing oil out by the grommet of the valve cover breather when I drag raced. Both lines from these breathers were plumbed into the back of the carb. I installed a catch can with a filter and plugged the carb inlet. Started car and while idling in the driveway, it was spraying oil out of the dipstick tube (with the dipstick all the way in) What gives??
 
To much crankcase pressure...check to see if your breathers in the valve covers are clear. Are you running a pcv valve?
 
That much blowby, try running header evac tubes. Thats alot of pressure!
 
My 383 bored and stroked to 496 was pushing oil out by the grommet of the valve cover breather when I drag raced. Both lines from these breathers were plumbed into the back of the carb. I installed a catch can with a filter and plugged the carb inlet. Started car and while idling in the driveway, it was spraying oil out of the dipstick tube (with the dipstick all the way in) What gives??
At WOT the small lines cannot keep up, there is almost zero vacuum so the blow-by has to force it's way thru there, and when it hits the choke point, the pressure finds a new place to escape. Be glad it popped the dipstick and not the rear mainseal. .
Some breathers have one-way valves in them, check yours. If they blow both ways,then your engine seems to have a ring-seal problem
 
Plumb the valve cover breathers to rear of the header collectors. They sell EVAC kits to accomplish this.
 
Why do you think the breathing catch can is not taking care of it? Is something stopped up in the crankcase?
 
There are PCV valves in the valve cover breathers. One way, out. I don't really want to dump oil into headers. Car has 10.8:1 pistons.
Thanks to all of you for your responses.
 
Short version - it's hurt. Take some cylinder pressure readings. If you can do a leakdown on it. It's broke.
 
At WOT the small lines cannot keep up, there is almost zero vacuum so the blow-by has to force it's way thru there, and when it hits the choke point, the pressure finds a new place to escape. Be glad it popped the dipstick and not the rear mainseal. .
Some breathers have one-way valves in them, check yours. If they blow both ways,then your engine seems to have a ring-seal problem
its spraying oil at idle per OP. there may be other issues If the lines are to the back of the carb, they are above the butterfly (timed port) so they are offering no vacuum until the carb is cracked. If they are below the line, then that is a vacuum leak waiting to happen. are your valve covers baffled under the breathers? I had a valve cover that had a baffle that was coked up beyond passing gas. It wasnt a Mopar but same principle.
 
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