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CatalinaLover80

Question about a pontiac 400 engine

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Is the positive crankcase ventilation important for the pontiac 400 motor ?

It's important for all motors.  You will always have a certain amount of BLOW-BY past your rings and into the crankcase. This is not only exhaust, but unburn't fuel as well.  (imagine what that's doing to your oil) The PCV is vacume back into the intake.  Much like an EGR valve your reusing the hot gas and recycling.  This helps with keeping the fuel and the hot exhaust gases (inside the crankcase) from destroying your oil, helps lower overall engine temp as well. Most older engines will also have breathers in the valve covers to help with excess.  But thats spraying all over your valve covers unless you have the factory set up with a tube and filter going back to your air cleaner housing.

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This explains alot .. I had a mechanic work on mine and he has the hole for pcv valve on the back of the valley pan completely closed off .. So i loked underneath and it looks like my seals are leaking theres oil all over the bottom of my oil pan.

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PCV is only a couple bucks and sounds like a new length of hose to a vacume port as well.   


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I'll second what justa said.The unburned gas fumes etc will ruin a motor in no time.Changing oil is cheap as well,once its hooked back up though after a few miles alot of the crap will naturally get burned out of the oil.(get a new mechanic as well)


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Follow your diagrahm.  You should have a plugged off vacume port somewhere already.  Measure your new length of hose to that.  Unless you have recently changed your oil, I agree with Indy... that would be cheap insurance.  Hope that relieves some of the pressure off those seals.


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Have you changed anything on your distributor?  


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Recheck your firing order.  Pontiac goes in a "counterclockwise" pattern.  It will seem to idle fine until you give it gas, if you have the firing order wrong or in the wrong direction around the cap.   18436572  Line up your timing marks, pull the cap. Usually #1 is on the pass side, see where your rotor is pointing. (The only way to make 100% sure your not 180 off, is to pull the valve cover. Turn the engine over by hand, follow your intake runner for #1 to the intake valve. After the intake opens, your on the compression stroke. Now line your timing marks. )  Where the rotor is pointing is your #1 follow the firing order counterclockwise around the cap. 


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Just the cap and rotor and an ignitor kit

You installed a pointless ignition module in your distributor?

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I switched my Sunbird over and regret every minute of it.  If the car gets wet....will cost me 115.00 for a new module. I have to carry spares. VERY EXPENSIVE.  When it's running, it's cool.  Kept my GTO points set up.  Still running the original set I put in 5 years ago with NO prob's.


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I have no idea what setup you went with. I'm using the Mallory Light trigger. I just bolted in using the existing screw holes. If yours was the same, you should be able to put the points, condenser and correct rotor, right back in.  Are you using the stock cap?


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