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I get oil up the dipstick tube at high rpm. I have a 496 chevy (gen 4 stroked). It has a 10 qt pan. I have 8 in th pan and 1 in the filter. Below 3500 rpm it is good to go. If I run above that for a few min, I get oil coming up and out the dipstick tube. Any thoughts will be great!! Thanks in advance!

Mike
 

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I would do a leak down test to see what you are leaking by the rings.

What type of crankcase breathers do you have on the motor?
 

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Engine only has about 12 hrs since built. I have a pcv on one valve cover and a breather on the other.
 

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I would do a leak down test to see what you are leaking by the rings.
I agree, even with low hours it's possible the rings didn't seal up well for some reason, or possibly something related like upside down rings(don't laugh, a friend's engine build by a reputable builder years ago had all the 2nd rings upside down.
 

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Engine only has about 12 hrs since built. I have a pcv on one valve cover and a breather on the other.
Lose the PCV, with any kind of camshaft duration at all they will not do enough work at high RPM, you need way more breather and quite possibly a puke tank, better yet a vacuum pump ;)

But seriously, open the breathers up and release some more pressure from the crankcase and you should be golden...

What oil are you using?, it's difficult to get a motor to "cut in" with synthetic non racing oil.........:)bulb
 

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Most engine builders put a spring or wiretie them down. I had to on mine before the puke tank,On mine it had a small K&N 2in breather,the hose to it was 3/8,it would spray oil out it on a hard run. The Whipple sc uses the pvc on star side and the SMALL K&N . I put a Peterson puke tank on it,That solved all oil problems.I also had it made with 2 #12s just in case I needed to put the pvc side in it also,the one side worked fine.I don't even smell the blowby when ya run it hard,its very little oil in the puke tank at the end of the season,:D

My thinking is that the small hose it built up a lot of velocity caring the oil with it,with the #12 line to the big tank,it would have low velocity and wouldn't carry oil with it.


ring leakdown was 6-15%,loose bore.the oil in tank is from one season worth,heres some picks 8.40psi boost

hopethis helps
Rob:)
 

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Discussion Starter #7
Thanks for all the replies. I am wondering if it could be caused by the dipstick tube being in the oil in the pan. I am thinking of pulling it out and cutting it down so it is above the oil level.
 

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21 Daytona
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its caused by internal crankcase pressure, find out whats causing that and dont worry about cutting the dip stick tube.
 

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Crankcase pressure is usually normal at high RPM. Like Morg said, leak the motor and make sure you rings seated. If so, you just need more breather capacity.
As far as the dipstick, I never run them in a high performance/racing application. I pull the dipstick assembly and JB weld up the tube. With 10 qts in the pan, you'll never lose enough oil to be a problem and not notice it in the bottom of the boat. You also are into the valve covers often enough to make sure the oil looks good.... IMHO no need for a dipstick.
 

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Thanks for all the replies. I am wondering if it could be caused by the dipstick tube being in the oil in the pan. I am thinking of pulling it out and cutting it down so it is above the oil level.
Try running 8 quarts of oil total. I have a 10 quart pan but everything works good at 8 quarts and no crank splash.
 
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