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I'm considering pressurizing the rocker shafts on my '55 292. I know there are at least a couple of methods, pinching off the shaft drain tubes appearing to be the easiest. My concern is about possibly starving some other part of the engine for oil. It looks like the output of the passenger side shaft goes to the timing chain. I don't know where the oil from the driver side tube goes, distributor/oil pump drive gear maybe...? I'm pretty sure a few guys here have done this so I'd like to know what method you used and the results before I pull the trigger. TIA for any advice.
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Ted (11/19/2020)
Here are some more thoughts on the subject. A major difference between the FE engines and the Ford Y is that the FE engines had hydraulic lifters while the Y had solids. I am excluding the 406 and 427 Fords from this discussion. With hydraulic lifters, the rockers are loaded against the shaft at all times which means there is no period of relaxation of the rocker to the shaft. In this instance a pressurized rocker shaft will force oil in those locations that normally would not get it. The Ford Y on the other hand does have that period of relaxation of the rockers to the shafts and simply relies on gravity to feed oil to the bottom of the shafts. The overflow tubes do allow the shafts to stay full of oil thus eliminating air pockets while at the same time allows the flow of oil through the shafts to be increased thus carrying away the excess heat generated there. Another plus to the overflow tubes is the right side of engine tube providing additional oil to the timing chain set that it would not receiver otherwise. The oil trough on the early engines worked in tandem with the oil flow tubes to insure that the oil did indeed get on the chain. As already mentioned, the root of the Ford Y top end oiling problems was with the use paraffin based oils of the time. The Y was designed originally for the modern multi-weight oils that were introduced at the same time as the Y but not all owners saw fit to use those oils from the onset. I do still see Ford Y engines with 300K miles with the overflow tubes still intact and these engines are still providng oil to the rockers. These high mileage engines all run a good quality oil which is routinely changed. A big fail point on engines being rebuilt now is with the softer than stock cam bearings that are being used. The cam bearings end up wearing much quicker to the point that the groove in the center journal of the camshaft journal is pushed into the bearing thus either restricting the oil flow to the top or shutting it off completely. Part of this accelerated wear comes from using valve spring pressures that are now much higher than stock. Common fixes for this are using a center camshaft bearing that has a groove machined on the back side of it, cutting the groove in the center camshaft journal deeper, or machining a groove in the center cam bearing hole in the block that allows the three holes there to be connected thus eliminating the need for the groove in the camshaft. A recent cam bearing for the Y from Engine Tech (made in South America) is made from a harder material and has thus far helped considerably in stopping the aforementioned problems associated with the softer cam bearing material. For stock engines, I use the overflow tubes. For performance applications where the valve spring pressures are increased, I will convert the shafts to a pressurized system. All the Harland Sharp roller rocker arm assemblies I prepare are set up for pressurized oiling as these use bronze bushings within the rockers which are prone to galling if they starve for oil. Thats kinda like my '56 the 292 is still running without a rebuild, sat some 30 years before I got it running again. Still uses the overflow tubes and on last check had oil flow at the rockers when I ran the engine with the covers off to get to temp before making my valve lash adjustment. I been meaning to double check mine though as well as check the valve lash as some of them when I did a simple check did seem to be a little tighter than I set them initially years ago. But I have been running VR1 oil in mine since I got the engine running again. First 20w50, now 10w30 as its easier to source locally now than it was when I was first needing the oil. Before sitting the car was running multi weight oil I know as in the back of the car on the floor was two cases of Exxon 10w30 oil cans from the late 70s early 80s.
1956 Ford Fairlane Town Sedan - 292 Y8 - Ford-O-Matic - 155,000 mi
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I have been meaning to double check mine though as well as check the valve lash as some of them when I did a simple check did seem to be a little tighter than I set them initially years ago.
Rusty I know you know this, but some reading this might not, valve lash clearance tends to get tighter over time, not looser as it might be supposed. The old adage "A tappy valve is a happy valve" has some basis in truth as far as that goes. The valve doesn't spend very much time on the seat, but this is the primary method of cooling, a too-tight valve lash can lead to valve burning or other problems. I really find the whole valve train stuff kind of interesting.
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There is a thing called valve reversion where the valve sinks into the head lessening the clearance, probably because of the seats. I had this happen on a long trip (east to west coast) in my TBird. Had a valve job done and all was ok. Tedster (11/29/2020)
Rusty I know you know this, but some reading this might not, valve lash clearance tends to get tighter over time, not looser as it might be supposed. The old adage "A tappy valve is a happy valve" has some basis in truth as far as that goes. The valve doesn't spend very much time on the seat, but this is the primary method of cooling, a too-tight valve lash can lead to valve burning or other problems. I really find the whole valve train stuff kind of interesting.
54 Victoria 312; 48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ
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There is a thing called valve reversion ...
Valve recession ... 
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valve recession is posable but highly unlikely with a y blocks. cam and lifter wear as well as rocker and shaft wear,rven with some oil at spill tubes, indicates some oil is getting to some rockers and some valve train.. tho with todays oils from rebuild to high miles and heavy valve springs some seat and valve recession is posable
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It's been my understanding valve recession was usually or at least often associated as a result of the use of unleaded gasoline, esp. with high speed highway use and/or heavy load operation. In addition to providing anti-knock properties to gasoline the addition of tetraethyl lead compounds to motor gasoline provided some protection to valve seats at high temperatures.
I'm a little hazy on which engines were particularly prone to this problem, Ford (and others) used stellite seats or good steel on some engines (from the 50s thru 60s) some engines didn't need them? But some engines were notorious for sunken valves, designed for leaded gasoline and operated into the unleaded era.
Are Y-Block heads known for soft steel in the valve seats? Leaded-gasoline wasn't the only choice back then either, seems to me Amoco gasoline was specifically sold as an unleaded choice long before TEL was banned for automotive use.
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