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so here is the deal, my motor, was spitting some oil out of a valve cover breather. After reading nearly every post on here i have discovered what i think is the problem. The engine is a 62 283, rebuild with a mild cam, an early edelbrock intake with three deuces(stromberg 97's), thats about all that is relevent here, except that it has maybe 10 miles and about an hour or so of run time. basically, when i bought the engine from the machine shop they had pluged the hole for the road draft tube with a freeze plug, and because of the early intake and strombergs there is no real way to run a pcv valve. Now, that i learned from this site that it should have said road draft tube i am thinking that is the majority of the problem, possibly exasperated by the rings not being completely set yet. so this leads me to ask...what do you dudes think? and ...anyone have a road draft tube from an early small block laying around that i could buy.
 

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Don't use the road draft tube. I do not understand why you cannot use a PCV system. All you need is a vacuum source and some valve covers made for PVC. If the carb does not have a vacuum source you can tap into the intake under the center carb and install a fitting.

Vince
 

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Marcel
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road tube

I always heard them called vent tubes. Whatever the engine has to breath to let the blowby from the rings get out of the block. vented caps in the valve covers well help to bleed it off, why can't you drill a hole in the intake for a vaccum hook up, or maybe vent it into the air cleaner, you have to change the air filter more often. I'd check the law in your area about polution from the tube. here if it came from the factory, its legal for that year model only.
lots a luck.
 

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If you don't want to put a hole in those valve covers, I have seen where a PCV was adapted to that road draft tube port behind the distributer...........
 

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Yeah, you need to get a PCV valve on there. Fitting it to the draft tube opening will work fine, and you need to keep the vented oil filler cap.

If I'm not mistaken, those engines originally had an optional PCV valve (California) that would have replaced the draft tube... don't know if any of those are still around.
 

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How do you add oil to the motor? The total vent system in the early days worked like this. The oil filler neck was fitted into a hole in the intake manifold that basically dumped into the oil galley. The valve covers were completely sealed. The neck was capped with a perforated cap that had a wire mesh to act like a coarse filter. The road draft tube was installed at the rear of the block portion of the oil galley and ran down the right rear of the bell housing to a point that was near the bottom of the tranny. The end was cut on a diagonal to create a slight low pressure and helped to scavenge the pressures from the ring blow by. The PCV system replaced this. The blocks were no longer had the road draft tube seat milled into it and the intake no longer had the oil filler neck hole milled in and a large threaded hole was tapped into the intake manifold near the base of the carb. A hole was added to each valve cover. One side had a sealed cap and was used to add oil to the motor. The other side could be configured a couple of ways, but both involved the PC valve which is nothing but a check valve that only allows air to flow from the valve train area to the base of the carb or intake manifold port. You now have blow by being vacuum drawn from the oil filler side head, through the oil galley and up through the PC valve head to the intake manifold for the purpose of being burned vice dumped to the atmosphere. All you have to do is to decide on how you want yours to work and that decision should be made based upon the hard ware you have. If you fill your oil through the intake, then find your road draft tube and seal up your valve covers. If you fill your oil through your valve cover, then go with the more modern version.

Trees
 

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Some early oil fill tubes had provisions for a PVC. (66-68)

I think I Saw them in Year One or Classic Industries.

Not too pricy either

Bryan
 

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Here's a pic of the PVC adapter used by Chevrolet in the mid-'60s. It bolts into the hole where the road draft tube used to live. The PCV valve screwed into the back side of the carb base and a hose connected it to the adapter. Fresh air was drawn into the crankcase via a filter that also served as the oil filler cap, on a filler tube at the front of the intake manifold.

 

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Jim's part is correct. If you are running the original intake with the wire mesh cap, all you need to do is run a hose from the pictured part to the carb PCV port.
 

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Sure, any engine will benefit from a PCV instead of the old road draft tube. I can't say if that piece will fit on your Buick engine, if the block opening is the same size you're good to go.
 
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