I have a 98 XJ 4.0 that my son drives.

It has been losing coolant, and overheated on him last week, so we decided to change the radiator, water pump and thermostat yesterday.

When we got everything together, it got up to temp, and was holding at just above 210, which is pretty normal, especially during the summer in Florida, so I sent him out for a test drive.

When he returned, the temperature was still in the same range, but when he cut off the engine, we noticed steam starting to come out of the hood.

Opened the hood to find a stream of steaming coolant shooting from the side of the engine from somewhere above the exhaust manifold connection point.

I suspect that we have the dreaded blown head gasket, but would like confirmation from any more experienced folks before we start tearing the engine apart.

Looking for advice. If I pull the head, how do I know if it's part of the problem and not just the gasket? If we do this, I only want to go through the exercise once.

Thanks in advance!

Can you take a photo of this? The exhaust manifold connects to the side of the heat, there's no coolant there. Head gasket is far below all of that.

There is a test kit which detects exhaust gasses in the coolant. This is a very good test when a head gasket or head problem are suspected.

It won't tell you if it's the head or the gasket (or even a cracked block), but it will definitively tell you it's time to pull the head to inspect, or not.

Thanks, I will check this out tonight. Could it be a freeze plug? I couldn't get too close when it happened because the engine was hot and there was a stream of 200+ degree liquid shooting out the side of the engine and I didn't want to get scalded.

Freeze plug is possible. Hard to say without pictures.

Turned out to be the two freeze plugs on the side of the block, closest to the firewall. Got them out, and they were rusted through.