1993 D21 KA24E: Loss of power, Overheating

[dhuestis]

Hi,
I just went through the 2.4L in a 1993 D21.

When taking it a few test drives it has the following issues:
-Overheats
-Thermostat doesn't seem to open until overheated.
-It's fairly doggy and once it warms up to around normal tempo it starts loosing power even worse. To the point that it stalls under full throttle.
-An intermittent cylinder miss.
-#4 cylinder has what appears to be water on the spark plug. That cylinder quit firing on the last test drive.
-All of the cylinders have 135 psi compression.
-The fan clutch is working fine and the belts are tight.


Here's what was done during the rebuild:
-Had a machine shop go through the head. They stated that they pressure tested and it was ok. The head was warped pretty bad and they straightened it in an oven and then milled it flat.
-Machine shop polished the crank
-New rod and main bearings (Standard)
-New rings and pistons (I believe it was bored 20 over)
-Machine shop pressure tested the block.
-Cleaned everything spotless before assembly.
-Tightened everything to torque specs
-New timing chain, guides, and tensioner.
-New oil pump.
-New fuel filter
-Did not tear down the intake assembly.
-Flushed cooling system
-Removed the coolant bleed screw when filling
-Running 10W-30 Rotella Oil


Here's what happened before the rebuild:
-Employee was driving it. He said it overheated, lost power, and stalled. He tried to restart it immediately after it stalled but it would not fire at all. It spun over like it had no compression. There was coolant sprayed inside the engine compartment.

Here's what I found upon tear down:
-Blown head gasket.
-Oil in coolant.
-Only about two quarts of oil was in the pan.
-The "U" shaped coolant hose was blown.
-Most of the timing chain guide had disintegrated and was laying in the oil pan.
-One of the pistons was scored.
-A couple of the rod bearings were down to copper.
-One of the main bearings was down to copper.
-The oil pump internals were pitted and worn.
-All of the plugs looked fairly good. They weren't oil fouled.


Before it stalled on the employee:
-Drove it for about 2 months.
-Lifter rattle and rod knock for about a month.
-Seemed to have excessive blow-by.
-Somewhat low power.
-Leaked about a quart of oil every 100 miles.
-Timing chain would not stay tight.

Anyone have any ideas?? Thanks!

[Tommywalton]

All of the issues at the top section are happening right after you rebuilt it? Only a couple of ways water can enter combustion chamber.