Hi all,

My head gasket on the disco blew a month and a half ago. There was steam coming out of the tail pipe in large quantities, and the coolant turned brown. I decided the smart thing to do was replace the head gasket. When I finished the job, I noticed a coolant leak coming from the intake manifold at the back end of the engine (yay inspection mirrors) when I fired her up. I took the intake apart and put some sealant (high temperature silicon made specifically for engines, I didn't do this the first time because I am stupid) around all the intake and coolant ports on both sides of the intake manifold gasket in hopes this would fix the coolant leak. put it all back together again and fired her up for a second time. Fuel went everywhere, that is when I realized I forgot to plug in the fuel line on the back of the intake manifold! I took the vortex thing and the ignition box off and reconnected the fuel line. I put it back together again. I fired her up, and all seemed normal while the disco was idling outside the garage. I bleed the air out the cooling system while refilling it while the vehicle was idling. I noticed a little bit of steam coming out of the tail pipe, but thought nothing of it because my old '77 dodge does that every morning. I decided to take the disco for a test drive around the area to make sure all is well before I took it to work the next day. The disco ran great for about a mile, then I looked in the rear view mirror. There was a castrophic amount of steam coming out the tail pipe. I said a few words I shouldn't have said and turned around. On my way back to the house the temp gauge shot up like a stabbed rat and the red light warning me of the high engine temperature came on. The service engine soon light also came on. I got home quickly and all the coolant was gone, and the neighborhood was covered in a thick layer of disco fog. I think that there could be a problem with the gasket that seals the vortex to the intake manifold, and it may be leaking all of my precious coolant into the engine. I know this isn't difficult or that expensive to replace, but do you guys think this is the problem now? Or is it the head gaskets again? This is becoming a frustration in my life, how hard would it be to do an engine swap with a simple 5.7L general motors engine like what Overfinch did to the p38 Range Rovers in a Disco II?

 

"Vortex"??? I'm going to guess you're talking about the plenum or intake manifold?
Anyway, there is no way that coolant can get into your engine from the plenum chamber the only area where coolant even comes in contact with the chamber is on the drivers side where the throttle body heater is located. What codes is it throwing to give you the CEL? Did you torque the heads down EXACTLY as specified? Another problem these engines have is cracked blocks, did you pressure test the block when you had the heads off? Sometimes on the pre-2000 engines the cylinder liners would slip and then the block cracks and you get combustion gasses in the coolant. When it does have coolant in it does it bubble from the bottom hoses on the tank when running? A 5.7 liter engine will tear that Disco apart!!!

 

To sum it up, YES I would say your enine is probably leaking exhaust into the coolant and coolant into the cylinder(s). There is no other way coolant can come out of the exhaust. Have you pulled the plugs yet? What do they look like?

 

Don't take this totally wrong, but if you can't do a easy head gasket replacement, I would suggest you try an engine replacement, which probably isn't needed anyway.

 

Thank you all for the input. I haven't had time to look at it any due to school and work... I'll look at the plugs later and get a reader to see the codes. Yeah, the 'vortex' as I put it, is that planer thing with the throttle body that sits on the manifold. I did not pressure check the block as I did not even think about the sleeves slipping, but I hope that's ok :/. I'll post back here later tonight on the developments.

 

Is it possible that you made some mistake somewhere during the head gasket replacement? If it were a cracked block before you started, I don't think that the leak would have gotten any worse. To lose ALL the coolant so fast like that? It could very well be something you did accidentally while changing the head gaskets. How much mechanical experience do you have?

 

did you clean the engine while doing headgaskets? did you change the oil. Hopefully you have some chemicals in your engine and or water in your oil? And a bad coolant leak?...
or maybe a bad bleed? Dunno