Help with oil leak in a sbc

[allchevys]

I have just rebuilt a motor (a sbc) and I found a leak in the bottom end. It done this before I redone the motor and its doing it again. when the rpm reaches 5500 and above it spays oil on the exhaust and fills the inside of the car with smoke. I narrowed it down to the oil filter area. its dry everywhere but there is a drip on the bottom of the filter. I have put 4 differant types of filter on this and everyone does the same thing. Im at a lose now. if you drive it down the road and dont get on it its fine.
Anyone got any ideas on what to do.
Thanks

[ztlonewolf]

try checking the area where the filter comes in contact with the block,could be something keeping the filter from gettting a good seal.

spreading a little bit of oil on top of the filter prior to installation will help it seal better

[allchevys]

I checked it out before and the area is clean (scotch brite) and I did put a little oil on the seal and I never over tighten the filters. hand tight and a 1/2 turn. getting very frustrated with it now. I never had this problem before.

[oldandtired]

Do you have the filter bypass blocked?
Dave

[allchevys]

no its open. Im changing the adapter plate that the filter screws onto (I have cleaned the old one and didnt see any defects) But I figure its worth changing just to see what happens. thats the only thing I didnt change when the motor was redone.
Thanks for you input on this.

[allchevys]

Well just changed filter and adapter and took it for a spin when I hit 6800 rpm and the shift light came on the oil filled the car with smoke again. Im lost now and Im giving up. its around the filter area but Ill be SOB if I can find out what it is :cry:

[johnracer]

Question.....how is the crankcase vented? Maybe it's building pressure and leaking at the weakiest point. Just a thought
Johnny

[allchevys]

I have an evacuation tube from the drivers side valve cover down to the header and a pcv valve on the pass. side Im thinking its a preasure thing but I dont know what to do to stop this. Not to mention I cant see anything leaking at the pan or the rear main

[gnsrule]

Tighten up the filter a tick more? Try a full turn, the worst you get is a PITA filter to get off. I had 1 blow one time, fortunatly it was on the dyno and not the track. That wouldnt be good.

Craig

[gnsrule]

BTW, You sure its not a valve cover leaking ? When you hit 6k the fan is blowing it off the head and onto the exhaust ?
With a PCV, when your at WOT it only sees low to no vacuum, with only one evacuation tube, you might not have enuff evacuation to handle the blow by. Ditch thew pcv and run a breather and see what happens, or ditch the evac tube for a breather. How tight is the motor ? If the blow by is excessive, nothings gonna fix it except a bag of cash.

Craig

[johnracer]

Is this a street car with mufflers? If so, the evac tube may not be working at all with backpressure. If it's a race car w/open headers, it really needs evacs on both banks and make sure the checkvalves work.
I'd try a pair of breathers on the valve covers just to see if crankcase pressure is the problem....
Johnny

[allchevys]

Thanks to both you guys I will try the breathers on both sides first and go from there.
Its a street car now with super 40 flow masters and 3" all the way back. the motor is pretty tight since it is for the street more than race now
that is one bad car you got there hope you hit the #.

[allchevys]

Hey Craig. I had to use a strap wrench which crushed the filter like a can and I used a pipe on the handle. the filter was only on there two weeks and hand tight with a 1/2 turn for some reason they get tighter by themselves (Im talking about the filter now) LOL thanks and will let you know what happens if the rain stops here tomorrow

[kwkracing]

Sounds like the oil galley plug under the driver side head in the rear of the block deck is not tight. Leaking oil, running down and on to the filter. and exhaust.

Have to pull the head to tighten