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PCV Valve Tri Carb

BlueRidge2

Jedi Hopeful
Offline
I recently read a how to article on pcv valve installation on a BJ8. If I remember correctly it was by Fine Spanner.
Since I have no power booster to pull vacuum from I will be pulling it from the intake manifold. Can I pull the vacuum from 1, let's say just the rear manifold or do I have to pipe all 3 together in a common plentium? If I do pull from one will it affect carb adjustment or balancing of the carbs? And I noticed fine spanners pcv valve was horizonally mounted, would it function better in a vertical postion. Thanks Bob
 
Hi Bob, I tried many years ago to fit a PCV to a stock BJ8 engine using the rear intake manifold connection. My experience with them is that on the BJ8 they will work at low rpm. However, because the Vacuum is so low on these engines at speed the valve will not function properly. In my case it caused the engine to spit oil out of the dip stick tube all over the engine compartment. Actually, unless the engine is plagued with a lot of blow by there should not be excessive positive pressure in the crankcase.---Fwiw--Keoke-?
 
keoke, oh lord forgive me for attempting to correct anyones "spellin" but i think hes trying to say "plenum" -- p.c.v. valve? what will the judges think? -- oh my! -- as if i could give a --- about "dah" judges,/bcforum/images/%%GRAEMLIN_URL%%/crazyeyes.gif me thinks the problem be someplace else on the engine if there be a problem at all, :(, does he havtah pass some kind of inspection? or sumthin?--what up? /bcforum/images/%%GRAEMLIN_URL%%/smirk.gif
 
Some PCV Valves are rated by the lbs per square inch it takes to make them positive. A lower rating may have solved the over-pressure in the oil pan.....FWIW

Alan T
 
/bcforum/images/%%GRAEMLIN_URL%%/savewave.gif

No Anthony, using a PCV in the engines has the advantage of inverting the crankcase pressure. This inturn relieves the stress on the engine block seals. Using this technique can virtually remove all oil leakages from an engine.---Keoke- /bcforum/images/%%GRAEMLIN_URL%%/yesnod.gif
 
Hi Bob,
Don’t you already have a balance tube on the manifolds? I asked a vacuum balancing question for my brake booster forgetting that I had the tube already
confused0091.gif
. My front manifold was the only one that had two additional holes tapped for getting vacuum. This photo shows where I piped for the brakes (The tube with the arrow). Norm Nock’s tech tip book has the PCV valve horizontal also.
201549-CIMG0196.jpg
 
Considering the oil puddle it doesn't work that well in the later MGB engines and they are always negative pressure unless the side cover hoses clog.

Alan T
 
The only original parts I see in this image is a thermostat outlet,two horns and a Tudor bottle. Nice,though.

Alan T
 
Well Alan, I guess that depends on the definition of “original”
winking0015.gif
. Oh, the voltage regulator came with the car new, but it is a hollow shell now.
 
using a PCV in the engines has the advantage of inverting the crankcase pressure. This inturn relieves the stress on the engine block seals. Using this technique can virtually remove all oil leakages from an engine.---Keoke- /bcforum/images/%%GRAEMLIN_URL%%/yesnod.gif [/quote]

This is my objective. Thanks Keoke
Greg, You are correct. I didn't even think about the balance tube that is already in place.
I haven't run the engine long enough to even know if I have a problem but may try this just as a precautionary measure.
Thanks guys Bob
Nice looking engine Greg. Whats up with your head bolts. Look's like they have holes in the middle?
 
Hi Bob,
Thanks, the head studs (and 12 point nuts) are from the nice folks at ARP. The holes are for Allen head sockets to make installation and removal of the studs easier. No need to use jam nuts anymore.
 
Tried a PCV valve once on my BJ8 and increased a small oil leak at the rear of the valve cover to a very significant one. Replaced the gasket on the valve cover, but I also removed the PCV valve and did not try it again.
 
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