Major coolant leak at driverside near firewall
 

WELL JUST WHEN I GOT THE 3 AMIGOS FIXED NOW I HAVE A MAJOR COOLANT LEAK AT THE REAR OF THE ENGINE ON THE DRIVERS SIDE. TOMORROW I WILL BE GETTING THE DYE AND BLACK LIGHT SO HOPEFULLY I CAN LOCATE THE LEAK. DOES ANYONE HAVE ANY IDEAS WHERE THE LEAK COULD BE COMING FROM I DONT HAVE COOLANT IN THE OIL SO IM HOPING ITS NOT THE HEAD GASKET. SOME RESEARCH SUGGESTED IT COULD BE THE VALLEY PAN?:eek:

It's common to have a leak at the rear of the engine basically anytime coolant starts leaking over the middle of the engine/valley gasket. Things to check:

-Throttle body heater and hoses connecting to it.
-Coolant pipe coming off heater core on passenger's side firewall into lower intake manifold (o ring can go bad).
- Large metal coolant pipe connected to front of lower intake manifold that is connected to I believe the upper radiator hose (also another o ring that can go bad.)

Please exercise using lower case letters... It looks like you're screaming your question :)

Could easily be valley pan, perhaps the throttle body heater plate, heater pipes. Head gasket can have these symptoms - white smoke, sweet smell in exhaust, water gurgle sounds under dash (combustion gas in coolant), overheating, coolant in oil, coolant leaks.

Page from RAVE attached with all the hoses that can leak. Keep coolant topped up, don't want to overheat while working thru this.

thanks for the info the truck has never overheated i guess as long as i keep an eye on my fluids and i dont smell any antifreeze in the exhaust thre intake hoses are not leaking. i did take off the intake manifold when i rereplaced the crankcase position sensor. could the gasket be leaking?

Don't wait for it to get worse or you stand the chance of making a boat anchor out of your engine when the seal totally fails and you don't pick up on it quit enough.
Go do a coolant pressure test for 18#'s for 15 minutes to find the issue.

Beast running hot.....
 

Need help as well. 2000 Disco II, 97k and I've been through the wars with the Beast. Purchased in Jan 2002 with just over 30k miles and since I've dropped a small fortune in repairs. Two head gasket repairs, catalytic converter and have endured the 3 amigos and now the 2nd episode of coolant leak issue. Because of my job, Beast was in storage for just over a year. Started running hot today so I shut it down....looking for help.

PS

1. Running hot - if you mean the over heat warning light came on, that is pretty hot and can certainly cause damage. If you mean at the top end of the scale, same thing. The D2 measures the coolant temp sensor (ECT), controls a number of things, and drives the temp gauge with computer controlled pulses. If coolant temp is withing a range of X to Y, it makes needle point to 9:00. Above 9:00 and you have exceeded the high end of the normal range and have started overheating.

2. If you have a scanner that can read live data, or an Ultra Gauge (a gauge that plugs into the OBDII port) - you can see the raw digital data the ECU uses. So you could see that you were at 195, but in a minute you are pushing 220, so turn off and fix something else, don't wait for gross overheat. Pix of ultra gauge attached.

3. Since you didn't give us much to go on, here is Santa's grab bag of overheat items in no particular order:

A. Coolant level - should be mid point in coolant container (one poster put in two gallons in a 13 quart system!)

B. Fan clutch - when warm, engine off, spin fan by hand and release - should not continue to turn for more than one revolution. A free wheeling fan clutch does not provide required cooling at idle and slow speeds. Has almost no effect at 55 mph. Cupped side of blades toward engine.

C. Electric fan - did it come on? Normally set to turn on at 212 F, off at 202 F.

D. Belt route - belts put on wrong can make water pump run backwards, etc.

E. Water pump - older pump will begin to wobble and leak, you can see the pulley wobble when looking from the side at idle. Pix of pump impeller, scale, plus eats metal when wobbles.

F. Thermostat - if stat does not open up, truck will overheat at various speeds. Stat has metering holes on top that can be blocked. IMHO it does not have enough holes, and the stat takes longer to heat up and open than it should. Pix of clogged stat holes.

G. Radiator - it, the oil / tranny oil coolers, and the AC condenser could be clogged with gunk, mud and restrict air flow. Radiator could have calcium build up for failure to use distilled water and antifreeze., or Dexcool sludge. Commercial flush may help. New rad over $200. Clogged radiator will show up cold on bott0m and warm on top rows of fins (because bottoms are clogged). Can read with IR thermometer. Pix of cloged rad, and procedure attached for flush.

H. Head gasket or cracked block can make severe overheat. There is a combustion gas in coolant test you can buy from auto parts store for $50 that does over a dozen tests.

Running Hot...
 

Thanks for the info...heading out to change out all fluids to include flush, and go from there. I'll be back.

well it turned out to be the valley pan gasket. my mechanic did the pressure test like disco mike suggested. should i tackle this project myself or let my mechanic do it for $800. i figure while the manifold is off now would be a good time to replace the plugs and wires. are there any other things that should be address at this time.
thanks and merry xmas

The valley pan gasket rarely ever fails, nearly always leaks when the bolts vibrate loose, send me your number and I'll walk you thru this easy job.