I'm glad I found this site, it looks very informative. Hopefully someone has a idea to help with my problem.

I have a 99 Blazer and the engine stopped after making internal engine noises. I took the valve covers off and under one cover there is plenty of oil on all the parts. On the other side the whole valvetrain is dry. So I'm not sure why one side has oil and the other side doesn't.

I thought it might be a cracked head with a coolant leak, but I removed the head and it checked out ok. The machinist that looked at the head thought it might be low oil pressure, but it seems strange only one side has this problem. The machinist thought a plug on one of the oil supply tubes might be bad.

An ideas?

 

Sounds like something is plugged. I would have the oil galleries in the head checked. The heads are oiled from the cam bearings.

 

There are no oil galleys in the heads. All of the oil for the valve train comes up from the lifters, through the push rods, then out onto the rockers.

You could either have a plugged oil galley in the block, plugged lifters, or plugged push rods.

Here are some oiling schematics I have found on the net. One thing to remember is that much of the oiling system in these engines remained the same throughout the years.
92 CPI Oiling Diagram -

89 TBI Oiling Diagram -

 

Thanks for the replies and taking the time to find those charts.

Since all 6 pushrods on the passenger side of the engine are dry, it sounds like the oil galley is the problem. So to unplug it, does one take off the galley plug that is behind the timing chain? Is this something that can be fixed without removing the engine. I'm not sure how hard it is to get the plug out and replace it. I don't want to drill things out in the oil passage, unless I have to.

 

I believe that the plugs are at the back of the engine.