New Hampshire CMP Barn 2011- 2012 HUP Overhaul

[Phil Waterman]

Hi All

Well, I’m looking for comment from some of you who have restored 216 cu.in. Chevy engines. As you will know from previous posts I make it a practice of running engines on a test stand before putting them into the truck. I thought I was already to put the rebuilt original engine back in my HUP and was doing a long run (50 hour plus) on the engine to really get the temperatures fully equalized so I could do a finial adjustment of the valves. While I was doing this I noticed that at a low idle of 450-400 rpm the engine is only producing 5-6 PSI of oil pressure not unusual for 216s but, when I removed the valve cover I discovered that the oil flow out of by pass for the rocker arms was a lot less that what I every remember seeing. Flow from the individual rockers was OK but the total oil flow running out of the upper gallery is less than I remember from previous engine rebuilds.

Here is the list of what was done on the engine that would effect oil pressure and flow:

• Crank ground and all new fitted main bearings.
• New cam and cam bearings
• New rocker arm shafts
• New oil pump
• New block to pan oil fitting.

What have I already checked:

• Put a valve in the oil line to the oil filter to see if too much oil was passing to the oil filter- no affect on oil pressure or on flow in the valve gallery.
• Checked the oil bypass control valve to be sure I had assembled the gaskets in the correct order and that the poppet valve didn’t have something under it. Everything looked OK.
• Took sample of oil doesn’t smell of gas and seems to flow like new oil, color light caramel.

If you wonder about the long test run on the test stand being a lot of fuel, it is but I manage to time my engine running to winter. With the engine exhaust hard piped out of the shop, running the engines is doing double duty, running in the engine but also heating the shop at the same time so I’m not burning any propane to heat the shop.

Wanted to ask for comments before I start tearing the engine down.

In particular how much oil have other people noticed running out of the rocker arm bypass tube in well run in engines? My memory is telling me it should be a good steady stream just under ¼ “ diameter.

Cheers Phil