Just put in ultra gauge, what temp does this thing need to run at and what temp is to high

 

also what is the downside to running with no stat in

 

OK no stat = coolant goes through rad to fast to cool off

 

OEM is like 195*f stat some go to a 180*f stat depends temp where you live and condition of fan and radiator

 

there is similar thread about this over on discoweb. most of the guys who are techs are saying that 190-205 F is pretty normal and in fact optimal.

i do know some guys run the cooler thermostats and are happy with the lower temps and poorer fuel mileage.

with ambient temps in the 70's my '96 runs around 183-188 F on the highway and in the 190's in stop and go driving. this is with a system that needs a flush and refill. and 203,000 miles on the odometer.

 

When's the last time the water pump viscous coupling (fan clutch) was changed? With belt attached and tensioned pull up on the fan, does it move upwards? If it does the water pump bearing is shot. When is the last time the water pump was changed? Have you looked at the impeller?

If you keep overheating the engine (hoses hard) you will eventually be replacing a head gasket - just a matter of time before one lets go with that much pressure. I would troubleshoot the **** out of the cooling system BEFORE you run it again. There is a simple reason and it's up to you to find it otherwise it's gonna get much more expensive than just replacing one part or rodding the radiator......... Know what I mean Verne?

 

I put a 180 in my 98 to replace a 195 that had stuck partially open. Temps on my UG run 178 to 186 on the road and once or twice up to 200 in stop and go. I am considering going to a 195. My gas mileage sucks - like 10 MPG; would higher running temps improve MPG? And if so how much of a bump do the experts say I might expect?

 

Water pump had just the littlest amount of play in it, so replaced it with one out of my other dead rover that was only a year old, then had radiator from said dead rover flushed and checked by rad shop, I installed it and now it is running at a cool 185+/-.


Thanks to all that chimed in

 

from the reading i've done we need a temp of 190 F to burn off moisture and other crap in the oil.


i don't know what kind of MPG increase you would see. there are so many different factors that play into fuel mileage. if you are mostly stock and only getting 10MPG then you probably need one or all of the following; new spark plugs, 8mm wires and front O2 sensors.

i'm currently getting around 10.5 to 11 MPG but i will be replacing the aforementioned parts soon.

 

I did new plugs and wires when I got the truck, which eliminated 8 or ten general and individual cylinder misfire codes and I also did all new fluids. I still get the occasional P1314 which my other scanner says could be the crank position sensor. I did not do oxygen sensors, but they all seem to be in range on the UG and it runs in closed loop with no oxygen sensor codes.

My Disco is running a fairly narrow temp range with the 180 T-stat between 178 and 183 and doesn't normally get above 185, so I guess I should switch to the OEM 195 thermostat if it needs to be above 190.

When I put the UG in our 1999 Dodge minivan to run up some gallons used so I could try to calibrate it for the Disco's low MAF values, that 3.3 V6 aluminum engine was running around 205 degrees: not sure what T-stat is in it, but its spec is 195 degrees and it has a fairly new radiator.