99 Chevy blazer
4.3L v6
4wd and 4 door
135,000 miles

I have a problem. A few months ago I replaced the gaskets to our blazer's intake manifold. I got it all back together and the passenger side of the engine wasn't getting any oil.

I took it all apart again and cleaned the rocker arms, hydraulic lifters, and push rods. I figured it was because old gasket or dirt got in it. I made sure that the rods went in the same order they came out.

I just put it all back together again and the engine is still knocking. I know the engine timing is good because it doesn't backfire and will accelerate fine and not backfire. The distributor is sitting all the way down like it should, so the oil pump is working and the other side is getting oil.

I finished a compression test and all cylinders are getting 170psi. The sound is coming from the rocker arms. And there is no oil getting to rocker arms on the passenger side. I'm out of ideas and figured I should do some reasearch before going into the engine blind.

Does anyone have any ideas?

Thank you very much, I greatly appreciate it.

 

I don't know much about the 4.3 block, but I'd bet the lubrication system has not changed much in the last 50 years as far as oiling system/hydraulic lifters go. There are oil galleys that run to the lifters. The lifters take in oil and push it out the top when the cam lifts the lifter/rod/rocker. The oil pushes out the top/center of the lifter and forces it up through the push-rod and onto the rocker where it is then thrown around in the head from every lifter.

Therefor, you would most likely have a plug somewhere inside the block.

 

Yeah that's what i figured. But I pulled all the push rods, lifters, and rockers out and cleaned them all. In one of the lifters and rods was a piece of dirt or something. Then I put it all back together and the same problem exists. I don't understand where else it could be clogged at.

Also I forgot to mention that on the oil pressure guage on the dash, it's getting good oil pressure. Just incase someone wanted to know.

One last thing, when I did the compression tests, I noticed that the spark plugs on the passenger side were black. And the ones on the driver side were clean. I don't know if that would be of help. I figured that it might be valuable information. If anyone has any ideas please help. I want to get this project done.

And thanks again for the help, I really do appreciate this because I'm stuck

 

So this is what I've done recently.
I figured the hydraulic lifters may have been plugged up because when I ran the oil pump (with an oil pump primer tool) there was oil getting to all the ports where the lifters sit.

Now I placed those in correctly and doubled checked and torgued everything back to the specifications I found in the Haines instruction manual.

And set the rocker arms in the special way they're suppose to.

But NO oil is getting up to the top off the engine because it's still knocking. I pulled the valve cover off and there is no oil what so ever. The oil pressure is great and you can see in my previous post that everything should work.

Does anyone know why this is? And I doubled chech to make sure the rocker arms and push rods went with the same hole they came out of.

I do not want to put a new/used engine in the blazer if I can fix this darn thing.

 

*I merged your two threads on the same subject so everybody can follow what is being done.*