I have a 92 vin “w” CPFI engine, I have put this engine in a jeep.
I had to change sump/screen pickup for the oil pump because I changed the pan to a sorter pan for ground clearance. No problem with pressure.
I changed the oil filter mount to the Astro van style and put an aftermarket cooler on it.
No problem with oil pressure
Engine was idling rough and found the nut kit to be leaking so I replaced it. I used a GM gasket kit. I timed out the engine and test drove it. Drove 300 ft to end of driveway turned left and stomped on it and got a lot of valve tap so I shut her down. Thought I bent a push rod I pulled the valve covers and found I have no oil coming to the top of the engine BOTH SIDES. The AutoMeter gage says I have 50 PSI oil pressure.
I have pulled the distributor and have tried to push oil though the engine with an oil primer with no luck.
I have pulled the oil pan and everything looks to be normal.
If I screwed up and put the gasket in wrong on the intake could this be the problem?
-or-
Any thoughts or similar problems?
Brian

 

Something has to be restricting the oil galleys that feed the lifters.

Is your oil pressure sensor/feed from the stock location (back rail of the engine block on top)?

 

I put a "T" were the 90 degree elbow was for the stock sender> I run the stock sender and the Autometer gage
It is just to odd both sides are not getting oil

 

Here are a few images I was able to dig up. The first is for your engine specifically:


The second is a rear shot showing the oil galleys for an '89 TBI motor:


The biggest difference is that the 92 CPI motor has a balance shaft and the motor depicted does not. This changes the oil passage locations a bit, but not too much. It will give you an idea of how you can read oil pressure and still have lifters tapping. As you can see, the oil pressure gauge port comes straight off of the main oil feed galley to the crank without any other interruptions. If there were a restriction in the oil feed up to the cam bearings or into the galley supporting the lifters, it could definitely starve the top end of the motor.

 

From my first post I was not clear. I did have a water leak on the intake just above the #1 cylinder so I did pull the intake and fixed it. Could I have screwed up the gasket set. I used rags and vacuumed out the valley before reassembly.

The engine is relatively clean with no wax buildup. On the rear view, were the main oil galley passes the cam could there be a problem with the cam. Question, is there a oil sling on the cam to push oil down to the lifters?

Well I think this is what I have to do
(a) bench test oil pump
(b) pressure test oil filter/cooler for flow, remove oil sender and cycle oil though main gallery
(c) push a wire though the galleries I can get to

Would you hookup compressed air to the oil sender and force air though the system backwards?
Any other thoughts on things to do with out pulling the engine? I would hate to do that it runs strong.

 

I did not mention that because I do not see how you could have caused the problem by swapping out the intake manifold gaskets thinking of the oil galley. Anything that could plug up an oil galley would be caught by the oil pump screen. If it got through the oil pump, it would be caught by the filter.

The lifters are supposed to be fed by pressurized oil from the pump, not by a sling. The lifters are hydraulic so lash is taken up by hydraulic pressure inside the lifters themselves. Pressure gets pushed through the lifters and up through each push rod to lubricate the rockers and valves.

But now that you mention the IMG replacement, if you somehow got debris onto the lifters, it is possible that it could plug up the push rods. That may be a place to start, removing all of the rocker arms and push rods, cleaning them out with some degreaser.

Did you use a fiber scuff pad to clean the intake gasket surface? These type of scuff pads can lead to some weird problems with oiling systems.

 

But now that you mention the IMG replacement, if you somehow got debris onto the "lifters, it is possible that it could plug up the push rods. That may be a place to start, removing all of the rocker arms and push rods, cleaning them out with some degreaser.

Did you use a fiber scuff pad to clean the intake gasket surface? These type of scuff pads can lead to some weird problems with oiling systems."

I did use a scuff pad on a drill. but I plugged the drain at distributor and placed rags in the bottom of the valley. I then vacuumed out the valley when I was done. I even flushed it with oil and vacuumed it up.

I did use an engine cleaner before I pulled the oil pan because I thought the same as you about the pump screen filter and clog. I have to wonder if the filter was clogged enough to decrees the flow rate of the oil though the lifters and keep them from filling

The engine ran several time after the IMG swap until it was warm with know problem. The tapping started when I rev end engine to about 1200-1500 rpms and dropped the clutch on a dirt road.
I think if I go to the point of pulling the lifters and p-rods I’ll do the engine.
Thanks for the diagram on the oil galleys I had been looking for them
Keep the good thoughts coming?

 

I found in other post when rebuilding the top end the lifters have to be/ should be primed. Could it have been possible I drained the oil out of the lifters when I vacuumed the valley out?