The Stovebolt Site Forums The Shop Area Engine Shop Mystery pipe on '53 Chevy 216

I was reattaching the oil lines to my oil filter housing after painting it and noticed there is a small copper pipe behind the oil intake line that comes out of the block and back into a boss of some sort. I was just curious what it does/is as I can't seem to find it in the shop manual or FAM.

Thanks in advance!

Chris

That’s the pipe from the oil distributor thru the water jacket and up to the rocker oiler system. It’s only used on spray oiler engines like the 216.

That line passes through the water jacket at an upward angle and comes out under the pushrod cover. Then it goes up into the valve cover area to provide lubrication to the middle of the rocker arm shaft. The sheet metal cover beside it is the "oil distributor"- - - -a spring loaded control valve that blocks off oil flow to the rocker arms until the oil pressure to the main bearings is at least 15 PSI. The engine oil circuit is designed to sacrifice the rockers if necessary, while providing adequate lubrication to the crankshaft.

That flex line is WAY too close to the exhaust pipe. I'd suggest using a 1/8" NPT 45 degree street ell between the tee fitting and the flex line attachment point to give the flex line some extra clearance. A melted flex line there will empty the engine oil in a couple of minutes at idle- - - - -sooner at highway speed. Another approach is to use a 4" long steel or brass pipe nipple between the block port and the tee to move the whole works past the exhaust pipe.
Jerry

OK, thanks Jerry, I will look into moving it. I will say it has been that way since I installed the oil filter housing 35 years ago and no sign of damage when I removed them last week.

I have a tendency toward overkill where the oil supply is concerned. Spray oiler engines have very low oil pressure to begin with, and any pressure loss can result in a trashed engine in a very short time frame. The pressure port for the dash oil gauge and the oil filter comes right off the main oil gallery, so a leak there can become a disaster very quickly. The first clue a driver will have that something's going wrong is usually the rods knocking, followed by a crankshaft lockup, unless he's OCD about watching the oil pressure gauge.
Jerry

You can't tell from the closeup photo but the line is about 3 inches from the exhaust pipe. I drove it for about 30 minutes and put it on fast idle afterwards and I could hold my hand on the oil line at the closest point to the exhaust pipe, very warm but no where near close to melting. I am thinking about adding a low oil pressure light setup.

OK- - - -pretty good diagnosis procedure! On a hard uphill pull, that pipe can get very close to red hot, especially if the carburetor is running a little lean. That's when a flex line might try to melt. I've seen that happen on many dyno runs on some of the race engines I've built. It's also possible to fabricate a heat shield between the flex line and the exhaust pipe but putting a 4 or 6 inch long pipe nipple between the block and the tee is the quickest, simplest fix to give the flex line a little more protection.
Jerry

I ended up installing an oil pressure sensor at the Tee in the oil filter line. it goes to a relay and then turns on a bright red led that I installed where one of the screws for the inside windshield trim is. The circuit goes through the ignition switch so that when the switch is on but the engine is not started yet the light is on, when the oil pressure builds up the light goes out. I am pretty pleased with the results.