D2 running warm

[Mike26]

Hmmmm, your heat doesn't work and the aux fan will be on. My guess is air in the heater coil.

Yeah, the heat has worked about half the time in the past few days after putting in the new thermostat. Whenever the heat works properly, everything works great and there are no aux fans turning on. Whenever the heat doesn't work, the aux fans turn on after a while and I always turn it off. I have been parking it nose up on a hill at night and bleeding the system out the bleed screw every morning while holding up the coolant res.

 

[Ed Cheung]

Make sure it is bleed out properly, an warm engine will make the bleed process easier. But after many cycle if you still have air in the system, I will take it to a shop to check for exhaust in the coolant system.

 

[chemtool]

Yeah, the heat has worked about half the time in the past few days after putting in the new thermostat. Whenever the heat works properly, everything works great and there are no aux fans turning on. Whenever the heat doesn't work, the aux fans turn on after a while and I always turn it off. I have been parking it nose up on a hill at night and bleeding the system out the bleed screw every morning while holding up the coolant res.

You are not going to get it bled until you get the air out of the heater core. Pull the heater hoses off and back flush it with a garden hose the forward flush it and repeat until it flows freely.

 

[Some Dude]

What temp should a D2 be running? At idle I normaly see 221 with the Ultra guage. It drops a little when driving but my aux fan is always on when sitting. Just thought it was supposed to be like that. I don't think it has ever gone higher than 221.

My 4.6 runs 197 down the highway and 207 idling in traffic. Highest I've ever seen was 220. The truck was fully loaded for a week long camping trip, it was 100 degrees outside, and I was climbing 4k feet to the top of a pass.

 

[Mike26]

Ok, I got the scanguage and started tracking how the truck is running temp wise. It is very hit and miss with how it will heat up. Sometimes I can start it up and let it idle for 10+ minutes and never have it go above 195, and I can drive it around with a high temp of around 198. And other times I will be driving it it will start creeping up to the 210 range. It doesn't get hotter than 212, but that seems way too hot to me. The aux fans turn on around 205. I just drove it back to the apartment from class and and went to 207, dropped to around 204 while driving, and then I let it idle for about 10 min and it stayed right at 207. Could this be a failed thermostat that is opening too late? It is a brand new genuine thermostat, but I have heard of failures with the new ones on here before. I am considering doing the inline thermostat tomorrow afternoon.

 

[gmookher]

mine is the same. infact, I felt my old thermo was more consistent, but it was also 6 years old

207-210 is normal, and as designed tho I find mine runs constantly 195 to 209

 

[dmarchand]

Mine runs 198 highway, 209-215 in traffic. It has hit 242 on the hottest day in stopped traffic before I shut it down. Never seen that repeat.

My temps are consistent before & after HG job. 75K miles now and HG performed at 60K.

 

[Mike26]

Yeah, I regret throwing away the old thermostat. I am curious what temps it had the truck running at. Did land rover by chance switch companies that produce the 'genuine' thermostats? Maybe the thermostat quality decreased... More than usual

 

[adriatic04]

you are in the range. if you read rave and understand the ecu running the aux fans, etc. you will see that the tstat doesnt even fully open until 204, I believe. the d2, and I believe the 03/04 d2's run warmer than we would like. every person with a d2 here will have the same range, trust me, I have read about everyone of these posts.

when I changed my tstat the result was lower temps when driving, a little lower (3*) at idle. It has been a year + on my newer tstat and idle results in 201-208, driving is 194-201.

 

[Mike26]

Yeah, I've read most of the RAVE section about the coolant system. I guess I only noticed the fans turning on because it was the first 'cold' night in East Texas this year, and the trucks design has it run hotter when its cold out. Now that I have the scanguage tool and have a more accurate measure of reading coolant temps, I feel slightly more comfortable driving the D2

 

[Mike26]

Ok today was the first time I've taken it out on the highway, I drove almost 200 miles and noticed something interesting. Above 2500 RPM the truck cools as it should, but below 2500 it doesn't, even at highway speeds. I would be driving around 50mph and it would start to heat up, so I put it in 3rd gear to get the RPM's up, and it would cool back down nicely.

Does this sound like the radiator to anyone? Its original to the truck, 76,xxx miles, 9 going on 10 years old.

 

[Some Dude]

When you say it would "heat up," what temp are we talking about? I don't even bat an eye until I'm in the 215 range.

 

[Mike26]

at highway speeds it would go between 202-210 around 2400 rpm, but if I had to slow down slightly and let off the throttle, it would go up to the 215 range. But if I had it above 2500 rpm at highway speed, it would show 195-198 degrees, which seems more correct. I'm thinking this is a coolant flow problem, and because the radiator is so clogged up with junk that it isn't getting the proper flow until the pressure is high enough. So at lower RPM, the coolant is flowing mostly through the bypass system. Does this sound like a possibility to anyone else??

 

[wheelen disco]

Sounds like you still have air in the system

 

[adriatic04]

seems drastic for what you are reporting. I just drove 11 hours and monitored the ECT the whole time, as usual. I drove 76 most of the time, avg 69 over the trip. I was at 94* 95% of the time. I had moments when I was driving slower and even then the temps were at 201, coming off ramps on the highway I was at 199 then went to 201.

They are confusing to figure out.

 

[Mike26]

Ok so based on the numbers you are reporting, I think my radiator is clogged. It's going on 10 years old and I have no idea how often it was flushed before I took ownership of the truck. Every other part of the cooling system has been replaced in the past 6 months, so the radiator is the only thing left to do.

 

[adriatic04]

Ok so based on the numbers you are reporting, I think my radiator is clogged. It's going on 10 years old and I have no idea how often it was flushed before I took ownership of the truck. Every other part of the cooling system has been replaced in the past 6 months, so the radiator is the only thing left to do.

get the front of the truck really high on stands, after driving. leave the reservoir tank cap off and let it sit for a couple hours. you might have air in the system or your radiator isnt flowing well. I was at higher temps, but only a few degrees, like 205-210 before I changed my tstat.

what is your coolant/water ratio? do you have one of those little testers?

 

[Mike26]

Ok, I will do that tonight. The coolant water should be right at 50/50 because I've flushed it a couple times in the past week using dexcool and distilled water.

 

[adriatic04]

yes but keep in mind when you flush you arent getting everything out. Just the ratio and make sure it is close to 50/50

 

[Mike26]

Drove back from Plano to SFA and the truck did the same thing, runs great at 2500+ rpm, below that starts heating up to around 210 or so. Ordered a new radiator from Will (thanks again Will!) I'll get it installed this coming weekend and post my results.