The Stovebolt Site Forums The Shop Area Engine Shop Hollow head bolt

I was reading some of the old posts about this and was wondering where one of these bolts can be found. Someone mentioned Patrick's in AZ and Inliners but I had no luck. I also searched a half dozen of the other vendors but didn't come up with anything. Has anyone found this bolt anywhere? It's the one that is located next to the oil supply tube for the rocker shaft and is drilled out along its length.

I was in the same boat as you. I found mine on ebay, some guy was selling a bunch of them. Not sure if he has anymore though.

Thanks. Do you happen to have his contact info?

Make your own- - - -it takes about 5 minutes with a drill press.
Jerry

I question why you think you need one.
It is only needed when 1953-58 rockers are used on a 1959-62 engine.

The bolt that is currently in that location has no hole in it and it looks like a hollow bolt would be the only way oil could get to the rockers on my engine (235). I shot solvent into the hole for the oil supply tube shown in this picture:

[IMG]http://i7.photobucket.com/albums/y261/bohon/56%20Chevy%20truck/Rockercleaning006.jpg[/IMG]

The solvent never exited anywhere until I removed the head bolt. Once I did, there was clear flow out of the hole shown here, which is where the oil tube under the side cover attaches:

[IMG]http://i7.photobucket.com/albums/y261/bohon/56%20Chevy%20truck/Rockercleaning008.jpg[/IMG]

I triple-checked myself. With the bolt in place, there is no passage from the oil tube behind the side cover to the supply tube over the rocker shaft. When the bolt is out, the oil can flow.
I took the rocker assembly apart partly because it was very dirty but also because I haven't been able to adjust the noise out of it and I wanted to see what was going on. It turns out one half of the rocker shaft is destroyed, scored so badly I need to replace it.
I don't know anything about the history of this truck, so I don't know what was done/changed/replaced before I got it.

If you need to make a bolt here are some pictures of the correct bolt. LINK

So you don't have to drill very far up the bolt. Definitly looks do-able. Thanks for posting the link.

You guys that need the special bolt and don't want to drill your own.This guy has about a dozen of them special bolt



Tim

That's the guy I bought mine from. I hope he has more for you. If not the other guys posting here have great ideas

Thanks. I'm going to just drill out the one I've got.

I have done a few autopsies that had an externally slotted head bolt. Don't have a picture handy but grinding a slot thru the thread .060"-.090" wide by about 1/8" deep at least 1/4" longer than the threads should do what you need.

I do mine on a lathe, using the tailstock chuck to hold a 1/16" drill bit to make the center hole, then a V-block on a drill press table to intersect with the center hole. If you're careful with the setup, both holes can be done on the drill press. Don't forget to grind a slot across the head so it can be identified easily in the future.
Jerry

That's how I understand it,the bolt is supposed to limit oil to the upper end? Earlier blocks have a restriction in the oil feed to the rockers somewhere.
If you have no oil to the rockers you need to clean out the internal passages.

My 56 235 does not have any hollow bolts. The rockers get nicely oiled. However an interesting twist is that somewhere along the line the internal passages got blocked and an external feed line (1/8 copper) was added. It is tapped from the oil port on the opposite side of the engine that feeds the gauge and oil filter...

All internal passages are clean and open. The oil tube behind the pushrod cover carries oil to the port next to the head bolt in question, then up to the arched tube that supplies the rocker shaft. With the bolt out you can clearly see how the oil flows. With the bolt in, no flow happens. The only way for the oil to reach the rockers--at least in my case--is to pass through a hollow bolt.

I don't know what year your engine is, but there are a number if places a blockage can occur, even in the triangle area in the head gasket that transfers the oil over to the head bolt.

Just wanted to update this post. I completely disassembled my rocker arm assembly, cleaned everything, cleaned out the inside of the shafts (which were pretty dirty), and made sure the oil supply tube behind the pushrod cover was clean and clear. I have the hollow head bolt in place, too. Started the engine and ran if for a while and it seems like I'm still not getting oil to the rockers. No oil flows out the overflow tube up top. I pulled the threaded plug from the side of the head and it's completely dry. No oil flows out.
One thing I noticed. I used assembly lube when I put everything back together. It looks like oil is pushing up through the little holes in the tops of the rocker arms--kind of coming up through the assembly lube--but that is only happening on the rear half of the shaft.
I looked at a video someone posted here recently and you can see oil dripping down off the rocker shaft. Mine is definitely NOT doing that. Since I'm unfamiliar with stovebolts, can anyone tell me how much oil I'm supposed to be seeing? I poured some clean oil over the rockers before starting, just to make sure they'd be lubricated until the oil got up there, so I don't know if the oil I'm seeing is what I poured at the beginning or stuff that's been pumped up there.
If I wanted to use the bypass option and run a supply line to the threaded plug on the passenger side of the engine, can I tap into the lines going to my oil filter? Here are pics of those lines:

One of these lines goes to my oil filter, the other goes to the oil gauge:

[IMG]http://i7.photobucket.com/albums/y261/bohon/56%20Chevy%20truck/VR004.jpg[/IMG]

One of the oil filter lines:

[IMG]http://i7.photobucket.com/albums/y261/bohon/56%20Chevy%20truck/VR005.jpg[/IMG]

I think I know which post you saw recently and he was getting a little to much oil.
If you are not getting oil out of the plug on the plug on the side of the head It might be easiest to run an external line.

I think that is what I'll do. Can I tee off one of the lines going to the oil filter?

I looked through your photo album and question the oiler tube.Looks like it was broke in this photo. oiler tube
This photo shows what looks like a rubber hose slipped onto it.
rubber hose on oiler tube
As soon as you get oil flowing,I'm thinking the tube needs pinched close some.You'll get get more oil at the rockers.
Maybe someone will chime in and share their opinion.


Tim

You would tee off the supply fitting for the oil filter/pressure gauge.

Before you go to the effort of running an external line, try this little trick that a lot of us oldtimers used when these engines were daily drivers. Remove the drilled head bolt and fill the hole in the head about 2/3 with motor oil. Whittle or sand down a piece of hardwood dowel rod until it's a smooth slip fit in the hole above the threads, insert it into the hole and smack it HARD with a BFH, about a 3-pounder. The shock effect should clear any sludge out of the internal passageways in the block. Specialty tool suppliers like Lisle used to sell a special dowel sized just right for the procedure for guys who couldn't figure out how to make one out of a piece of broomstick.
Jerry

You are good, HL. Thanks

Tim, yes I followed a suggestion here on the forum to slip a hose over the broken tube to direct the overflow oil back down a drain hole. If only I had oveflow oil! I've since removed it to see if any oil comes out and it does not.
Hotrod Lincoln, will this procedure clear any blockage far back inside the block? Because I know for a fact that the passage through the head is clear and the oil supply tube behind the pushrod cover is clear as well. I'm thinking maybe it's something toward the back of the camshaft or further. Will the pressure from this trick blow back that far?
In case you're wondering how I know those passageways are clear, I shot compressed air into them to make sure. Also, I pulled the drilled out head bolt this afternoon and ran a piece of welding wire through the holes to make sure they weren't clogged. Is it just me or does that passageway look like it was designed to get stopped up?

I currently having an oil line coming out of the block which branches off in two directions: One sends oil to the oil filter. The other leads to the oil pressure gauge. If I tap a third line in that runs up to the rocker arm assembly, will that cause any problems with pressure or efficiency?

I have the set-up you describe on my truck - no problems.