LexSurfing

I've unfortunately come across a dark day for my dear old 1994 LS . Engine began overheating yesterday and stalling occassionally when idling. My current diagnosis is a cracked cylinder head gasket.

No matter the chosen way of treating such a malady I first want to drain the current coolant from the system and flush the impurities (I believed there to be only a small amount of coolant left since much of it was probably burned through the leak). I loosened the main draincock beneath the radiator and a small amount (1/2 gallon) trickled out steadily - milky white color...

I tried running water through the system by means of the coolant resevoir inlet. After filling the resevoir the level slowly dropped (as it was draining into the radiator I assumed). But the water didn't seem to make it to the radiator draincock. Deciding to run the engine with the heater on high, I noticed a slight movement of the water, yet it still somehow seemed clogged.

Loosening the two secondary side draincocks, I was annoyed to see that oil seemed to drip forth instead of the expected water.

I'm at a bit of a loss for what to do:
-Should I remove the thermostat? Would a new thermostat me necessary in this case?
-How should I go about flushing the system, and will this oil be flushed as well?

Any insight would be welcome!

cobalt91

Easiest way would probly be to remove the upper radiator hose and thermostat. Then use a garden hose to flush from the top down. No need to run the engine while your doin this.

python

iTrader: (4)

so u have bad compression in two cylinders that are next to each other? water in the oil? steam coming out of the tail pipe? i find it hard to believe theres an issue with the head gasket unless it over heated real bad. did u do a block test?
u said "my current diagnosis is"..so that means u diag'ed it? if ur not a trained mechanic i would stop and have it looked at by someone who knows wtf they are doing. and dont lead them to believe thats what u think it is..just ask them to tell u whats wrong.

LexSurfing

I was able to take the thermostat out and filled up the resevoir directly through the portal left by the thermostat. Yet the water remains stagnant and will not drain despite the draincock (main one only) being opened completely

j2b4o

The drains on the block are open or just the rad?