350 engine lost its oil pump prime?

[Jolly_John]

Hi, Gang. My 1971 Skylark with 350 has been sitting unstarted for about a year. I changed the oil and filter today (before starting the car). Then, I planned to start the car after cranking it over a few times with the coil wire grounded. My thought was to get the oil up and circulating a bit before the engine fired (since the car had been sitting). After this cranking, I reconnected the coil wire, the car started right up, BUT there was no oil pressure. I shut the car off after about five seconds, when the reading on the oil pressure gauge didn't come up.

I then spun the filter off, and there was no oil in it. I think that means there's no need to check the oil pressure gauge and sender. So, does anyone have ideas about my "no oil pressure" situation? I'm thinking loss of prime in the oil pump, but I welcome all ideas.

I've had mostly Buick nailheads in the past, so the 350 engine is new to me. I do have the shop manual, and will be reading that over tonight.

If the oil pump has lost its prime, is there any way to turn its shaft with a power drill to get circulation going? I recall accessing the oil pump drive through the distributor mounting hole on one of my old cars in the past. Don't know if the 350 oil pump is set up to do that, however. I really don't want to run the engine again at this point. If the oil pump can't be turned with a drill, am I going to have to remove the pump, pack it with vasoline. Or, should I begin by packing the pump with vasoline, and then spinning the pump drive, or cranking the engine with the coil wire grounded. I may be getting ahead of myself here, since some of you may have ideas for my lack of oil pressure, other than the prime being lost.

Thanks very much in advance for any help. John

Edited August 4, 2011 by Jolly_John (see edit history)

[wildcat1562]

Hi John

did you fill the oil filter as much as you could before putting it on, that seems to help

otherwise i would say the pump is bad

if it started the cam gear to the distributor shoud be good

so from there down is probably bad

you can take it apart right from the bottom to see, i think 4 bolts hold it to the timing chain cover?

Greg

[Guest brh]

I have heard of an oil pump losing prime because the oil filter and pan were left empty for an extended time, but not after an oil change. Above all I would not fire that engine up until you have established oil pressure, metal to metal with all empty lifters is not gonna make for a happy ending. You may want to pull the plugs and shoot some oil into those cylinders, spin the engine just to coat em.

[Guest brh]

Looked in some of my books and ran across one thing. Is it possible for the oil pressure release valve to be stuck?? Reason I am bringing this up is maybe its an easier solution than dropping the pan and pulling the pump. Sorry I don't know enough about the specifics to your engine, just a thought.

[wildcat1562]

the pump is in the timeing cover on these i believe, 4 bolts on the bottom

Greg

[JohnD1956]

Can you see if there is evidence of an oil spill under the pump? I'm thinking a compromised gasket on the oil pump's cover, or a broken gasket on the timing chain cover.

[lrlforfun]

OK JJ: I had one like that. The problem was a hairline crack in the aluminum timing cover. Mitch

[Jolly_John]

Thank you for taking the time to post all of the good ideas, Gang.

Over the weekend, I filled the oil filter by hand, tipped it over quickly, and screwed it on (messy!). I then took out all of the spark plugs, shot some fogging oil in the cylinders (didn't like the thought of really dry cylinders), and proceeded to spin the engine over with the starter (plugs still out). The oil pressure came up within just a couple of seconds.

So, it appears I have dodged a bullet here. However, I will keep the ideas in mind about the possible gasket problem or the hairline crack in the timing cover.

I do intend to use that procedure of filling the oil filter first on all future oil changes. I always do that on the vertical or tilted filters found on my other cars, but have never done it on the 350's horizontal filter before. Again, THANK YOU, guys. John

Edited August 8, 2011 by Jolly_John (see edit history)

[JohnD1956]

Great news. I usually fill the filter once and then let it settle. That renders a half charge and then I put it on half full. I did it once the way you indicated but I figure I lost half the filter's worth before I got it tightened.

[Guest G1987N]

I know it is a little late now since it does have pressure but, ,,, when I rebuilt the 350 in our "70" GS I packed the pump full of Vasoline to create a suction and used a oil pump primer tool made for the Chevy engine. The vasoline dissolves enough to not harm the engine and I usually change the oil after about 200 miles on a fresh rebuild to get all the cam lube and any other contaminents out. I have used a long thick straight blade screwdriver with the handle removed for the drill to prime a few engines, little trick from selling Speed Parts for 10 years.

Steve