273 Rocker Assembly leaking?

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jessy

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Hey everyone,
I recently inherited this build from a family member and am slowly learning the world of pushrod engines. I am putting together this 340 with a hydraulic cam, X heads and which i believe to be a 273 or Rocker Arm Assembly. All seems to be going well but when i went to prime the motor i notice quite a bit of oil pressure bleeding from one single rocker shaft washer on each side. Just wondering if this is normal or not? If so i would assume the one that bleeds should be opposite of the supply hole?
Thanks A Bunch

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So it doesnt normally bleed by when priming pressure? It's only occuring on two washers one on each head no mater where I put them
The torque on those shafts is pretty light. You will have to look it up. They are pretty easy to distort in the bolt hole areas. When they aren't round, they don't seal well to the cast rocker stands.
 
That shouldn't be happening. That shaft may have a crack in it.
 
Be a great opportunity to get them nanner grooved ones.
 
Also be aware that some service manuals INCORRECTLY list the torque of those bolts. They are 5/16, not 3/8 bolts so double check online for a 5/16 grade 5 USS bolt. Should be more like 15--17 ft lbs
 
This ^^^^^^^^^ ! My manual said 35 ft lbs. Broke a bolt off. 15-17 ft lbs is correct ! :BangHead:
 
I agree with the shaft being oval or possibly cracked. If it were mine I would remove the offending shaft and look it over good, plus check it for roundness.
 
Do you have any stock rockers and push rods? Since you're running a hydraulic cam, if the cam isn't huge, try stock rockers and push rods to see if the leakage goes away. Also, check to see if the shafts are installed upside down. The oil holes in the shaft are supposed to be on the bottom. If they are upside down, the shafts could be filling up with oil and the excess that isn't getting to the rockers is having to find a place to go.
 
My Shaft has two holes on bottom banana groove and oil hole pointed towards exhaust side. The notches did end up being opposite to what everyone else said oddly. And it only seems the be the washers. Because if I move my washer to the other spot it bleeds from that washer. And not from the spot it was previously in .
 
Do you have any stock rockers and push rods? Since you're running a hydraulic cam, if the cam isn't huge, try stock rockers and push rods to see if the leakage goes away. Also, check to see if the shafts are installed upside down. The oil holes in the shaft are supposed to be on the bottom. If they are upside down, the shafts could be filling up with oil and the excess that isn't getting to the rockers is having to find a place to go.
I unfortunately was only left with a set of the adjustable rockers and a set of cheap aftermarket aluminum ones. The aluminum ones are 1.6 ratio and too much for this application. It appeared he was changing to roller hydraulic but it was a nightmare. It appeared the rollers would open up oil gallery at every lift. Also pushrods would be rubbing heads that where already installed. It was put together by a shop here in niagara but very questionable
 
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