The Stovebolt Site Forums The Shop Area Engine Shop No oil to rockers-1950 216

Guys,
This is my first post in a long time. Recently my 1950 Chev 1/2 ton pickup (Not a daily driver, but run often) was off the road for a couple of months for brake work. On restarting, stuck intake valves which wouldn't free up with solvent. Pulled the head and cleaned the guides with a .45 barrel brush. Reassembled and it ran fine- compression 120-123 PSI, vacuum 19.5" but-- No oil flow to rockers.

Checked the oil line for blockage and found that it was totally free flowing. Now for the questions- this line goes to the oil distributor behind the exhaust pipe. Air into this line would flow across the valve plate (Under the distributor cover plate) and into the port leading to the con rod splash manifold. If no oil to the rocker line does this mean no oil to the rod troughs?

I'm really open to suggestions, but here is what I'm going to try:

Ignition distributor off and drive the oil pump with electric drill. 1000 pump RPM should give me 14 PSI on a warm engine. Will pump for a while at higher RPM and see if any oil to the rockers. If Not-

Pull sideplate and check for broken or leaking line in pushrod area. If Not the next step is to pull the oil dist. valve plate and look for what (?)- If oil pressure valve stuck closed this should be the problem, but I've never heard of this happening.

I have no clue as to the oil gallery layout in this engine. There is the oil filter drainback fitting just in front of and below the dist.cover plate, the rocker arm oil line fitting coming out of the casting and going up into the water jacket and, a little further back, a Tee fitting to the filter and the oil pressure gauge. Oil is flowing to the filter (line gets hot) and pressure gauge indicates (seems a little lower since head work).

The engine is clean inside- no sludge and has fresh 30 weight oil. Fresh gas too, since I suspect alcohol spiked fuel.

Anybody run into this problem before?

Bill Stewart

look on the old online chevy manuals, or get a manual. the oiling is very basic. You could check your radiator for oil in case the line is broke inside the water jacket. I suppose it is possible the oil distributor is compromised in some way. There is one thing I have learned, not much is impossible when it comes to mechanical things.

I don't see if you said you had oil pressure at the gauge when it was running, did it? If so that would indicate the oil gallery has pressure.

Your intention to drive the oil pump w/a drill to see if oil flows to the topend is good. Don't run the engine anymore until you can verify oil pressure at the gauge (or at the T fitting that feeds to the gauge and oil distrbutor).

The oil line thats behind the side plate if not positioned just right can rub against a push rod and get a hole worked in it. So if your drill test indicates oil pressure at the gauge but not to the topend, pulling the side plate would be my next check.

Good luck
Dave

Thanks for the contacts.

No oil in coolant. I was planning to blow out the line with compressed air, assuming that it was blocked, but puffed into the hose and was surprised to find no resistance at all. No oil or water.

The engine runs smoothly and shows oil pressure. I'm used to seeing the gauge peg on cold start and sit at maybe 12-14 PSI running. Seems lower, but its been hot here. Idle pressure with 30 weight about 8 PSI.

I'm not sure how the valve in the oil distributor works, which way it opens and how much pressure it takes to open it. Assume that it sits closed until (?) pressure opens it and allows flow to the rocker line and the conrod scuppers.

Will try to troubleshoot tomorrow AM.

Bill

Mystery solved> The pushrod did it.

Pulled sideplate and drove the oil pump. Leak behind line where worn by pushrod.

Next cleanup and sweat split tube over leak.

The rocker arm assy was well oiled when I pulled the head so it must have happened when I pulled the head.

Thanks for the suggestions.

Bill

Good find. let us know how the rest goes.