Oil Pump

Started wifes' car, all lifters are tapping. No oil getting to valve covers.
What I need to know is; Is the oil pump in the oil pan?
What is another way to check oil pressure on this car?
Anybody ever run into this before, no warnings at all?
Easiest way to replace?

I know someone here has done it. My wife lost my shop manual, and the Chiltons. It is cheaper to replace oil pump and gaskets than buy the shop manual from GM.
What I really need to know is were is the oil pump on this car.

The oil pump is on the crankshaft, on the timing end of the engine, with the pickup near the bottom of the pan. Go grab an Oil Pressure Tester from Autozone or somewheres, hook it into the pressure sender, and run the car at whatever RPM the booklet says..usually 1500-2500, and see what the pressure is. I've never heard of a no-oil condition to the valve covers, but I don't hear many oil starvation stories.

All the lifters are tapping really bad. Is there any other situation you can think of? I looked in the oil fill (with engine running) I didn't see any oil. Usually oil shoots out when the engine is running. Got me, give me an older ride and I could tell you what it is. These newer cars, everything is different. Do you have to remove the oil pan to replace the oil pump? or can you get to it without?

The whole drivebelt end needs to come apart, basically. All accessories (ps, water pump, tensioner, alt) need to come off, and it can be cramped working at that angle, but it can be done with the engine still in the car. The timing chain cover and the crank/cam sprockets need to come off too. It might just be a clogged oil passage. Did you check the rear valve cover for any oil spray? If not, you might have a bad pump. If so, suspect a blockage on the left (front) end of the engine.

I thought about that also. I will check the back valve cover for oil. Sounds like a pain to do a pump.

Its easier to do a pump than to do a pan drop, believe me.

Before you give up, get a new filter, fill it with oil, and spin it on. See what happens.

This question is very interesting since I just had to tow my sons car, just after New Years, back 150 mi from school for exactly the same problem. I did change the oil filter, but did one better. I ran the engine with the filter off and clearly could see that I had oil pressure to the filter, also at no time did the guage show low oil pessure, nor did the low oil light come on. Now does anyone know of a specific problem with an oil channel that goes to the top half of the motor? Does anyone know where that oil channel comes up to the top. Otherwise I was planning on pulling the rocker assyemblies off and checking under them, and maybe running a steel coat hanger down the channels.

This question is very interesting since I just had to tow my sons car, just after New Years, back 150 mi from school for exactly the same problem. I did change the oil filter, but did one better. I ran the engine with the filter off and clearly could see that I had oil pressure to the filter, also at no time did the guage show low oil pessure, nor did the low oil light come on. Now does anyone know of a specific problem with an oil channel that goes to the top half of the motor? Does anyone know where that oil channel comes up to the top. Otherwise I was planning on pulling the rocker assyemblies off and checking under them, and maybe running a steel coat hanger down the channels.

I'm lazy. I'd probably put a couple of quarts of kerosene in it and let it run for a few minutes (engine warm), then let it sit for a hour or so. Let it all go, refill with oil, prime a new filter and see how it sounds. I've blown out some pretty hogged up oiling systems doing this.

The oil pumps upward through the cam bearings, lifters, push rods, and onto the rockers, the runs through the return passages to the pan. When the returns get blocked, it will usually start off fine, then at higher speed, the oil light will come on (oil going to top end faster than returning to pan, pump starves), and if you stop the motor, it will show on the dipstick as being out of oil for several minutes until the oil makes it past the restriction back to the sump. Real common in some older Ford engines, haven't relly seen it on GM (not a recent one), but it could happen.

Some engines will have a complete loss of top end oiling if a cam bearing fails.

Thats sounds real interesting, never tried it, but it sounds like it's worth a try, before I start tearing the engine apart. I have no intention of getting rid of the car, it is in too good of a condition. Plus it's a PD package car, and I know I am good for at least another 100K on it.
Now my problem is not as you described, but is real noisy lifters, so I suspect a blocked oil channel up to the top of the engine. I'll let everyone know how it turns out, tomorrow it supposed to be about 40, so I should be able to do somework outside.

Kudos to jeffcoslacker for a fix that worked great. Immediatly after pouring kero in the oil the clatttering stopped and what I am guessing was the problem, a collapsed lifter ( a loud click coinsiding with a pop in the exhaust) cleared up. I ran the car at about 2500 rpm for 5 min drained the oil, refilled with new oil and filter, and the car now runs great. The car originally had a small tic in it, but that too is gone. Thanks again.

Just an update to my previous post. Our area has been experiencing some cold weather, (for around here) anywhere from -10 to around 0F at night. Last night it got down to about +5F and when I started this car up this morning I had some lifter tapping again, nowhere as bad as before. After about 3-5 min it subsided, For now I am just going to let the car warm up completely before use. I am also going to try the Kero trick again at oil change. I suspsect I either have some weak lifters or the oil channel is not completly clear yet. Thanks again to jeffcoslacker.

Just an update to my previous post. Our area has been experiencing some cold weather, (for around here) anywhere from -10 to around 0F at night. Last night it got down to about +5F and when I started this car up this morning I had some lifter tapping again, nowhere as bad as before. After about 3-5 min it subsided, For now I am just going to let the car warm up completely before use. I am also going to try the Kero trick again at oil change. I suspsect I either have some weak lifters or the oil channel is not completly clear yet. Thanks again to jeffcoslacker.

I would suggest changing the filter again within 500 miles or so now. Stuff that loosened up will continue to work it's way to the filter, and it may get blocked up with crud if you wait too long. Glad it helped.

My '97 has always had a noisy top end when started, especially in cold weather. I usually let it idle for a couple of minutes, then bring the idle up to about 2500 for a few seconds, and it is quiet. I can't tell if it's purging air from the lifters or if it is just the nature of it, but it has been that way since new, and has 117,000 on it now and sounds no different.

Might be the piston slap issue, that affects all those Gen2 3100s, I think. My 1999 makes noise at startup, but it goes after about five minutes or so. Its just the pistons having excess side clearence when cold, when the pistons warm up they fill the cylinder properly.

Might be the piston slap issue, that affects all those Gen2 3100s, I think. My 1999 makes noise at startup, but it goes after about five minutes or so. Its just the pistons having excess side clearence when cold, when the pistons warm up they fill the cylinder properly.

sounds right.:iceslolan

I think the first think I would check is the shaft that drives the oil pump. It is located in the top rear of the engine block where the distributor would normally go. You might have to remove the crossover exhaust pipe to access it.