ghaskett Posted December 31, 2013 Share Posted December 31, 2013 Have small amount of blow by coming out breathers, but not out of the tube...which comes out at the rear of the valley cover. I'm guessing that it is plugged. Is there a easy way to remove the tube...or clean it out? Thanks. Link to comment Share on other sites More sharing options...
JohnD1956 Posted December 31, 2013 Share Posted December 31, 2013 The tube is attached to the engine by a bracket behind the lowest bolt on the bellhousing. Passengers side. If it was plugged I imagine it would be right at the end of the tube. Otherwise chances are the filter for it is attached to the underside of the valley cover, under the intake manifold. But are you certain the tube is not working? Note, it is an oblong end that protrudes into the air stream under the car, causing a vacuum and sucking the fumes out of the motor while the car is moving. Fumes from the breathers while the car is stopped is not really an indication that the tube is plugged. I have noticed that sometimes my 56 will give off fumes from the breather in early spring after a winters rest. But that stops when I get the car up to operating temperature and drive it for a few miles. Link to comment Share on other sites More sharing options...
avgwarhawk Posted December 31, 2013 Share Posted December 31, 2013 The down draft tube only works when the car is in motion. The air flow under the vehicle creates a down draft in the tube that pulls air through the breather oil cap and exits the tube. When stationary it is typical to see vapor from the breather oil cap. Link to comment Share on other sites More sharing options...
ghaskett Posted December 31, 2013 Author Share Posted December 31, 2013 Thanks for the info. Very helpful. Link to comment Share on other sites More sharing options...
old-tank Posted December 31, 2013 Share Posted December 31, 2013 As noted, vapors from the breathers does not indicate a clogged draft tube or valley cover, but if the valley cover has not been apart, it probably is clogged: http://www.buickrestorer.com/valleycover.htmlAlso as noted, an extended drive will show a decrease in vapors.Willie Link to comment Share on other sites More sharing options...
bhambulldog Posted December 31, 2013 Share Posted December 31, 2013 I noticed an in crease in vapor on mine after a hard braking.Has anyone put a pcv system in place of the blowby? Link to comment Share on other sites More sharing options...
avgwarhawk Posted January 1, 2014 Share Posted January 1, 2014 I noticed an in crease in vapor on mine after a hard braking.Has anyone put a pcv system in place of the blowby?Some have used a oil cap with PVC hole/grommet. The PCV is plumbed to the air cleaner housing. Not sure how the hose was attached to the air cleaner housing. Welded a steel pipe I guess. Run a rubber hose from PCV to the welded steel tube on the air cleaner. The air intake from the carb pulls in the vapor. Link to comment Share on other sites More sharing options...
buick man Posted January 11, 2014 Share Posted January 11, 2014 (edited) Better to run a pvc to the base of the carb by tapping into the base plate. The valley cover can be removed and very often the inside brass or aluminum mesh that is plate set into the inner cover which the draft tube draws from can be encased hard with creosotes from decades and is now just a plug wad. The get to this one of course has to remove the valley cover, turn it over and delicately cut out the spot welds with a spot weld drift that does not have a center guide point or one that is very small since you don't want to tap through to the outside and have to fill it later upon repainting it. The plate can be removed along with the old flat faced mesh. Replacement mesh can be had in the form of copper or aluminum flat faced scrub pads found in kitchen supply centers. You need flat faced profiled mesh for the surface area it provides. Not just brillo or SOS scrub pad wire material. Whatever you get your hands on the surface face of the material needs to be at minimum 1/8 . Then spot weld back together. Care has to be taken when cutting out the spot welds as you can easily go through the outer cover creating a hole that needs to welded back in.If you want to install a pvc type lift from the valley cover to the base of the carb for example, gather up all your pieces, ie. vent, valve, tube and fittings. For proper Covert operations and hidden appearance Drill a hole toward the rear of the valley cover and install a fitting which will allow you to not only connect from the valve to the outside area of the cover but also allow you to run a 1/4 inch copper tube from there inside the cover forward about 8 inches or so. This helps to prevent internal splash up problems later clogging the valve itself. Then run your line over to the base plate at the rear on the firewall side to keep things covert to the base plate of your carb. This technique spares your air filter both in function and appearance not to mention all the upper internals of your carb thereby helping to keep those areas clean. This can be done by creating a tapped orifice into your existing plate to connect the tube. You can also get a lift base out of aluminum to help with heat sink problems by tapping into and installing that instead. This would lift your carb up a bit and create a little more positive vortex draw. The draft tube can then be reinstalled after putting a plate over the intake where it slides into the valley cover orifice thus rendering a stock appearance with no one the wiser except the environment.buick man always recommends preserving the natural stock beauty and essence look of the car and this technique preserves that mantra over chopping into rare air breathers, caps or valve covers as this always in the end looks " Hacky Motto" at best. Edited January 11, 2014 by buick man (see edit history) Link to comment Share on other sites More sharing options...
Paul Falabella Posted May 24, 2014 Share Posted May 24, 2014 My contribution to the filthy breather filter feature. Link to comment Share on other sites More sharing options...
Rooster Posted May 24, 2014 Share Posted May 24, 2014 David ---- excellent information, thanks. I'm looking to do this conversion. Did you happen to take any pictures during the process ? Link to comment Share on other sites More sharing options...
KAD36 Posted May 24, 2014 Share Posted May 24, 2014 (edited) Heres another approach to putting a PCV on. Its easily removable it you want to revert back to the original open breather. I'm hunting for another PCV valve as this one is pulling more flow through than needed to eliminate the vapor at idle in drive. I also cleaned the mesh out as Willie suggested and boy it was a mess. Good luck and have fun with it.http://forums.aaca.org/f162/pcv-system-1955-322-a-340918.html Edited May 24, 2014 by KAD36 (see edit history) Link to comment Share on other sites More sharing options...
buick man Posted May 31, 2014 Share Posted May 31, 2014 Ken: No I did not as I have not done this to my original cars but have known about this method for sometime now. However, this method is simple. The copper tubing is bent forward and running about 8 inches forward does 2 things best. Helps to create a more positive flow and keeps from having the pvc valve clog up if just otherwise positioned into the valley cover. This often occurs when installed in just the valve cover cap as mentioned above but without benefit of increased positive flow. This covert method has one drilling a hole in the rear of the valley cover near the vent tube orifice. The internal wire mesh once removed need not be replaced, instead the run of copper tubing connects into the pvc valve through the inner side of the valley cover, bends in a 90 degree to the front of the motor about 8 inches or so. One must secure the copper tubing so it will not fall out of the pvc valve so the utilization of a collar nut system around the tubing and a flare end setup will fix that. Then run a rubber hose to the base of your carb. Now the guy next to you at the stop light won't smell a thing except for the guy directly behind you might have a little more of a richer experience. Link to comment Share on other sites More sharing options...
MrEarl Posted June 1, 2014 Share Posted June 1, 2014 ghaskett, dirtdobbers love to make nests in these things. Most of the ones I pull off parts cars are partially or fully stopped up by dirtdobber nests. Run a screw driver or long piece of stout wire up it and see if there is blockage. Please report back what you find or your fix as suggested by others. Link to comment Share on other sites More sharing options...
Guest 54fins Posted June 2, 2014 Share Posted June 2, 2014 Timely subject. I am using a 425 with a 54 valley cover and valve covers. My concern is oil vapors, want to keep a clean engine bay. I used the down tube and a pcv valve in it and the down tube is sealed. The 322 valley cover had to be sliced to remove 1/4", But to my surprise the heads are surprisingly similar. It appears to be logical, but if there is a reason it won't work do advise. I was also going plug the oil cap vent, but if unadvisable let me know. I don't want any oil vapors but don't want to restrict the engine breathing. Link to comment Share on other sites More sharing options...
bhambulldog Posted June 2, 2014 Share Posted June 2, 2014 A pcv system only works if there is somewhere for air to come in to replace the vapors being sucked away.leaving the oil fill cap alone will allow fresh air into the crankcase and flow through the pcv into the combustion chamber to be burned off. Link to comment Share on other sites More sharing options...
Rooster Posted June 2, 2014 Share Posted June 2, 2014 I always thought modern engines these days were fully sealed and have a closed circuit where the crankcase is actually under negative pressure ? This also helps in combating oil leaks. Correct me if I'm wrong.So why wouldn't the older engines benefit from the same set up ? Link to comment Share on other sites More sharing options...
bhambulldog Posted June 2, 2014 Share Posted June 2, 2014 That's a good question Rooster, and I would have included the answer above if, supper had not called me away A 'closed' system has a an inlet that draws air through the the intake filter,If you want a' closed' system you'll have to tap in to the air cleaner, pipe that to the inlet to the crankcase. For a 'closed' system the air would enter through the air cleaner snorkel , then into the crank case (through the valve cover or valley pan), then into the intake manifold, and through the combustion chamber. An open system allows air directly into the crankcase (valve cover or valley pan) then into the intake manifold ...thereby eliminating the need for a pipe from the valve cover (or valley pan) to the air filter Link to comment Share on other sites More sharing options...
bhambulldog Posted June 2, 2014 Share Posted June 2, 2014 Here's a comparison view Link to comment Share on other sites More sharing options...
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