Short version, tl;dr - the UltraGuage warned us of a high coolant temperature issue that was a catastrophic water pump failure that we caught in time to save the engine.

If you don't have an UltraGauge, I highly recommend that you get one. I read the recommendations on this site and it was one of the first purchases when we got my son his first vehicle (2001 Disco 2). My son set it up with the coolant temperature as a main display item, and set an alarm at 220 degrees Fahrenheit.

The longer version is that my son was driving back from school and got an alarm from the UltraGuage. He thought it was the ongoing P0455 that he gets daily, but as he went to dismiss the alarm on autopilot, he realized that this was different - the temperature alarm. He called and we assessed the situation. Per my instruction, he blasted the heat and monitored the temperature on the last mile home. When he got home, I checked the coolant, and it was down, way down. There was no coolant in the oil. I added a gallon and a half of 50/50 coolant/distilled water mixture, and it seemed to hold it. We ran the Disco and the exhaust wasn't unusual and didn't smell sweet like coolant. I gave him a gallon of coolant mix, and he took it to school the next day with instructions to monitor the gauge and pull over to add coolant if it needed it. He almost made it the 3 or so miles to school when the UltraGuage warned him again. He checked the coolant and was down nearly a gallon. He nursed the car home after school and we put it up on ramps in the garage where I gave it a more thorough inspection. There was clearly evidence of a significant leak with liquid coolant on the driver side of the engine bay below the power steering pump. I topped the reservoir off and had him run it. No significant evidence of a spray in any of the common places. Then I had him rev the engine to around 2500 rpm and *holy heck*, coolant came pouring out of the front of the engine like a kitchen tap half open. I had him kill it immediately.

I wasn't sure what I was looking at, either a front cover gasket or a water pump leak. I don't have a pressure testing kit, and it was late in the evening, so I decided to hedge my bets and replace the water pump, thinking that even if it was the front cover seal, having a fresh water pump wouldn't be a bad idea. I proceeded to disassemble things, knowing I'd need to get a water pump (I already had a new tensioner, idlers and a belt that were going to go on in the spring).

Luckily I live near Rovers North and the team hooked me up with a water pump, hose assembly and a clamp. If you are on here, thanks guys, that was huge in being able to quickly get the Disco back on the road (and get my own vehicle back).

I got everything back together and refilled the coolant, started it up, and job done, leaks gone. Let it get up to temp, topped off the coolant, revved it a bit. Dry as a bone.

Two things I'm grateful for - my son, who quickly identified the issue and took immediate action, and the value of the UltraGuage as an early warning device.

Side note, my son said that the factory water temp gauge in the cluster didn't move from the middle of the range, or if it did, it wasn't significant deflection from its normal middle position.

Other note, I have NEVER seen a water pump fail this dramatically or catastrophically. I've seen many drip from the weep hole, have failed bearings, etc. But never one that just shot out water at a high volume like this. There was some coolant in the weep hole, but no shaft wobble or evidence bearing failure; it spun with appropriate resistance and smoothness. I'd note that the bolts holding the water pump to the engine didn't seem to be torqued well (I torqued to 28 Nm on reassembly, these were barely more than finger tight, and had no evidence of sealant on the long bolts). Anecdotally, the engine did have the head gaskets done by the prior owner, and I wonder if they did the water pump at that time and never final torqued the pump bolts? We didn't get any documented service history, so I can only speculate.

I see love/hate posts, but we also have the Extinct Inline Thermostat mod, and that has been a great addition too.

Last of all, yes, I should have replaced the fan clutch too, and will do that in the spring, it is an easy enough job to knock out quickly.

 

anyone that drives these that doesnt have a ultra gauge is not good

 

becarefull with new water pump, had one bad out of the box, these old new parts are crap

 

Thanks. We'll watch the temps and keep an eye for any indication that the new pump isn't working. The good news is that the water pump is an easy job - I spent more time making sure the sealing surface was pristine than I did actually removing and replacing the pump. I think I could do it in an hour or so next time.

 

I actually bought my Ultraguage first and THEN bought my Discovery.