Serious Coolant Leak after Overheating

[pyreneesexplorer]

Hello, I am a new member but have used the threads to fix problems before, 4x4 shift motor failures etc. I have a 1992 XLT 4x4 4.0L with lots of salvage yard scavenged Eddie Bauer interior/exterior trim parts. I recently blew a lower radiator hose and dumped all the coolant on a near 100 degree day. It happened so fast you can imagine the train of events, AC blew hot, hard knocking auto ignition started shortly thereafter, then temp guage pegged out. Luckily I was close to a convenience store so I coasted in and killed it. I let it cool down and then filled with 3 gallons of pre-mix, vented system, & topped off. When I started it up to vent system it ran rough at idle, OK at 2000 rpm & up. I drove the last ten miles home but began to notice a puff of white out the exhaust every now and then at highway speed. Now at start-up I get a cloud of white with coolant odor and excess condensate. I test drove and went through over two gallons of coolant in 30 miles. No coolant in oil evident, possible oil in coolant but have not yet confirmed. It is almost like the coolant is going direct into a couple of combustion chambers (causing poor idle) and being blasted out the exhaust without passing rings and getting into crankcase. I know it is likely a head gasket or cracked head. I am leaning towards head gasket and of course changing O2 sensor due to likely coolant damage but wanted to get any input this forum can provide.

 

[BrooklynBay]

Welcome to this forum! It does sound like the head gasket blew out. Connect a cooling system pressure tester to the radiator, and pump it up with about 10-15 LBs of pressure.

 

[Dopler174]

I agree, it sounds like a head gasket leaking into the pistons.

 

[pyreneesexplorer]

Follow-up Question to Response by BrooklynBay

Thanks to all for the responses. After connecting a cooling system pressure tester to the radiator, and pumping it up with about 10-15 LBs of pressure how do I differentitate between blown head gasket from cracked head?

 

[Maniak]

The only way I know is to pull the head and have it tested.. You have to pull the head anyway to replace the gaskets so I would just "expect to pay" for new/rebuilt/repaired heads and if they turn out not to be cracked then you saved a bunch of money..

BUT...

Expect them to be cracked.. its very common for them to crack when overheated...

If you do end up with new to you heads, try to get heads marked 93TM.. Currently you have heads marked 90TM.. supposivly, the 93TM heads are less prone to cracking (but they still do) and are less pourus(sp?).

~Mark