This week I will be getting my 1959 292 ci engine back from the machine shop , after a complete rebuild , I notice on the internet  there is one site that shows how to pressurize the the top end by plugging the rear oil holes and closing off the return tube - has anybody tried this idea, and if so how did it work ?  Neil

Here's a couple links that may help you decide.

http://www.y-blocksforever.com/forums/Topic10464-3-1.aspx

http://www.y-blocksforever.com/forums/Topic10464-3-4.aspx

   God Bless.   Tim                           http://yblockguy.com/

350ci Y-Block FED "Elwood", 301ci Y-Block Unibody LSR "Jake", 312ci Y-Block '58 F-100, 338ci Y-Block powered Model A Tudor

tim@yblockguy.com  Visalia, California    Just west of the Sequoias

The main problem with oiling to rockers is that the stock oil feed  groove in the camshaft is too shallow.I had mine ciut deeper to .034 I think it was.There was too much oil to the rockers after that so I drilled and tapped a restrictor to cut down oil flow and now it works great.

  

As mark points out, if your Cam is a stock replacement, you may have an oil supply problem. However, if your engine is completely reassembed, c/w new cam bearings, (hopefully properly installed) why not pre oil the rockers well, (before installing the distributor,) using a drill with extension & a suitable socket (ensure the socket does not fall off!) & turn the oil pump counter clockwise & see if you get a reasonable amount of oil to both rocker assemblies. If so there's likely no problem. Once the engine has been run in briefly, you can pull the covers & watch the oil supply with the engine idling. If no visible problem, don't worry about it.. Fully pressurizing the rockers is a somewhat controversial alteration..

Paul

I just recently "semi pressurised" my rockers. Mine has had minimal oil up there so I took a punch and hammered the ends of the overflow tubes blocked them by about 75% maybe a little more. I checked all this with the motor running and at about 2000rpm oil is now nicley flowing out the rockers and in between, seems quieter too. Still enough coming out of the ends of the tubes to do whatever it needs to.



"Came too close to dying to stop living now!"

Here's something I've never seen brought up in any comments about blocking the rocker shaft overflow tubes to pressurize the shaft.  Doesn't the overflow tube on the front of the right rocker arm shaft send oil to the timing chain and gears?  The overflow tube directs oil down through the push rod hole in the head to a trough area in the valley that directs oil to a hole in the front of the block which feeds oil onto the timing chain.  And the overflow tube on the left rear rocker arm shaft helps direct oil to lubricate the distributor shaft gear.  I remember seeing an oil flow chart in a book showing the timing chain and distributor gear receiving lubrication from the rocker arm shaft overflow tubes.  Would blocking the rock shaft overflow tubes restrict the amount of oil to the timing chain?    

buddy

Blocking them totally doesn't seem to be anything new http://yblockguy.com/yblock_009.htm , Im sure the overflow tubes are not the only only way those areas get oil [ oil slinger]. Maybe Ted or someone might elaborate.



"Came too close to dying to stop living now!"

As part of the original engine design, an oil trough was mounted above the lower timing gear to direct oil specifically to the timing gear set.  This trough was discontinued in 1956 with the thought process being that the excess oil from the right side rocker arm assembly still being adequate oil for the timing chain area.  Here’s a link showing the oil trough.

Timing chain oil trough 

 

If completely pressurizing the rocker shafts, then here’s a link showing what Tim McMaster has come up with to provide some additional oil to the lower gear and chain.  This helps to replace the oil that is no longer coming down the original path.

Pressurized timing chain oiling

 

Any engine modifications that do away with the additional oiling at the timing set will simply accelerate timing chain wear.  The link style timing chain used in the original engines is more susceptible to wear than the roller types of chains so this is something to keep in mind.  Although there is some oil seepage coming from the front cam bearing during normal running, it’s questionable if that’s enough oil to adequately lube the original ‘wide’ link timing chain that’s being used without using some of the oil that comes from the topend of the engine.

 

The original oiling system when used with modern oils does actually hold up well over the long haul.  Most of the problems with the early engines in regards to lubrication issues centered around the use of paraffin based oils (big no-no in the Y’s) or inadequate oil change intervals or both.  My own 272 has over a quarter of a million miles and it’s still std/std on the crankshaft with the rest of the engine only showing minimal wear.  This engine has been using TropArctic 10W-40 since 1955 and based solely on this, says a lot about the advantages of modern oils.  TropArctic has been around since 1954 and was actually the first multi-viscosity oil introduced for automobile use.

 

And here’s the link to a thread with links to several past threads talking about pressurized rocker arm shafts.  http://www.y-blocksforever.com/forums/Topic51052-3-1.aspx 

Doing a search on the site will bring up some more. 

Lorena, Texas (South of Waco)

Thanks Ted for clarifying this issue.  I was just concerned about hearing so many comments about pressurizing the rocker arm shafts without any mention of making modifications to compensate for the oil supply that would be lost to the timing chain and gears.   

buddy

Thanks for all your thoughts - I think  I will stay stock, as with a nice clean new engine my oiling should be good - I plan to use Shell Rotella with ZDDP - you guys are great. Neil