The Ford Barn - Pressurizing Rocker Shafts

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Pressurizing Rocker Shafts

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.

Re: Pressurizing Rocker Shafts

a lot of people were doing this for awile.now most have backed away from it.you dont need it for a street engine.

Re: Pressurizing Rocker Shafts

Check with Tim McMaster (yblockguy). I think he pressurizes them in all of the engines he rebuilds, unless the customer requests otherwise.

Re: Pressurizing Rocker Shafts

Quote:

I don't know where the oil from the driver side tube goes, distributor/oil pump drive gear maybe...?

Yes.

Re: Pressurizing Rocker Shafts

Just wondering, why do you feel you need to perform this modification?

Re: Pressurizing Rocker Shafts

I'm having my rockers refreshed soon, and will be using new shafts. Maybe I'm second guessing Ford's engineers but the oil flow to the rockers just seems on the weak side to me. Oil does flow to the rockers as designed and I have between 15 and 20 lbs. pressure at hot idle with 40wt as indicated by a mechanical gauge. I'd just like to see a little more going to the rockers to hopefully reduce wear there.

Re: Pressurizing Rocker Shafts

Are you pulling the heads during this rocker shaft rebuild? With stock springs, a relatively hot cam you should get years of service from the stock set up.

The problem with oiling the top end is rooted in the oil routing to the head and the fact that older oils used "back in the day" did a really crappy job of keeping the oil clean. The passage for oiling the top end make two 90s on it's way up' The oil hole in the block is off set from the hole in the head. There is a small groove in the head that hooks the two together. That is the culprit. Pull the heads and clean both holes up and down, clean the groove or enlarge the groove slightly and live happily ever after. New oils keep the transfer groove clean a gagillion times better!

Re: Pressurizing Rocker Shafts

I remember installing bypass lines from the oil gauge to the rocker arm shaft some how, was it through the valve cover ? Its been over forty years and my memory is not so good any more .

Re: Pressurizing Rocker Shafts

the kit contained a hollow stud to replace the one that held the rocker cover on.this fed oil to the shaft.i put one on back in 69.the right side never got as much oil and was the first to quit.

Re: Pressurizing Rocker Shafts

Hey Darrell it's been many years, I was just wondering if there was any problems later on with taking so much oil from the rest of the system. I remember it being a 1/8" copper tubing and no restricter.

Re: Pressurizing Rocker Shafts

Quote:

Originally Posted by Ford blue blood (Post 1953453)

. . . The problem with oiling the top end is rooted in the oil routing to the head and the fact that older oils used "back in the day" did a really crappy job of keeping the oil clean. The passage for oiling the top end make two 90s on it's way up' The oil hole in the block is off set from the hole in the head. There is a small groove in the head that hooks the two together. That is the culprit. Pull the heads and clean both holes up and down, clean the groove or enlarge the groove slightly and live happily ever after. New oils keep the transfer groove clean a gagillion times better!

Pictures...
The oil hole up thru the block is 5/16, the hole up thru the head is 1/4. Offset from each other approx 1 & 1/2 inches.
Depending on how well the head was cast or if it's been resurfaced the groove underneath can be shallower than originally designed. I've seen a couple that made me fairly concerned.

I remember removing a pair of head gaskets that had swollen a bit into the groove in the head, making it even smaller. Sludge could then more easily block the passage of oil.

I've been meaning to ask if other folks think cutting a small channel out of the head gasket right where the groove is might be a good idea. :confused:

Re: Pressurizing Rocker Shafts

it didnt hurt the oil pressure on my engine at any rate.it still had a good bottom end.most engines who got this were on their last.

Yoou Gotta Read This Post

For TECH Guys - Just Posted Today @ y-blocksforever.com

SOURCE - http://forums.y-blocksforever.com/Topic153967.aspx

Quote:

Ted - Co-Admistrator - y-blocksforever.com

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 providing 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.

http://www.y-blocksforever.com/avatars/ted23altered.gif http://www.y-blocksforever.com/files/tedeatonsig.gifLorena, Texas (South of Waco)

Now this 'ol boy (Ted Eaton ... not me) is smart and experienced. I pale by comparison, I have nowhere near this man's knowledge and experience.

There is much hidden knowledge (in past threads there) that fully explains the deficences of the FYB valve-train. It is fascinating reading.

Re: Pressurizing Rocker Shafts

Quote:

Originally Posted by dmsfrr (Post 1953511)

Depending on how well the head was cast or if it's been resurfaced the groove underneath can be shallower than originally designed. I've seen a couple that made me fairly concerned.

I remember removing a pair of head gaskets that had swollen a bit into the groove in the head, making it even smaller. Sludge could then more easily block the passage of oil.

I've been meaning to ask if other folks think cutting a small channel out of the head gasket right where the groove is might be a good idea. :confused:

Important factoids here. If one studies the FYB cyl head and valve-train design, it will become apparent why this was designed as it was.

Increasing pressure/flow to the arms will also allow excess oil to drip above the valve seals. FORD in the early Y used deflectors under the stands to divert excess oil to the drainage holes.

As for valve springs, it is best as to go with the advice of the cam grinder. The lifter has to follow the ramps on the cam and stronger (better materials) will be needed. Now you are increasing spring temperatures which throws another factor into the equation.

Also, valve springs lose temper with mileage, making them weak and leading to mis-fire and valve float/reduced RPM.

Even a OEM stock setup will suffer from spring fatigue at some point.

Re: Pressurizing Rocker Shafts

Can we all agree that frequent oil changes are cheap, and a great first step?