To totally ensure you don't have an air pocket I will slowly ride around the neighborhood with the coolant cap off, cycling the heat on and off in random intervals. Obviously don't overfill and belch out a bunch of coolant if you do have air in the system. I've had much better success with this than having it idle in the driveway to temp
D2 Cooling Issues
- Thread starter MStudt
- Start date
Yes, some vehicles have a shutoff valve in line, but D2's do not, having the heat on/off doesn't change flow one bit.
So all these years I've dealt with blasting the heat on high in the middle of summer for nothing. Shit
I think we may have found the culprit after all. But I'll answer your questions first.
The system was run through a machine a before the new t-stat was installed, and again afterwards. It was verified that the air was out of the system, and that there were no leaks. An inferred heat gun reading was done on all hoses, and it shows everything flowing like it should. The t-stat was opening fine, and nothing was clogged or blocked. The belt is also routed correctly, and all hoses are in the correct location.
Now onto my discoveries, and my errors. I notice the clutch had gone a few weeks ago, and brought this up on another couple forums. Members for both forums steered toward the pre 03 Disco's that used a two piece clutch/fan setup. This gave me an pre 03 clutch with a generic Dorman fan blade.
I reached out to Turner Engineering who we purchased the block from, and told them what I was going through. I told them about the clutch/fan setup that we're running, and gave them the part numbers. They came back, and pretty told me that was the issue. Stating that the clutch did not have the capacity that the Rover engine needed, and the the fan was not seated into the shroud correctly. After checking the fan I notice that it needed to be moved forward at least an inch to sit in the shroud. I went ahead and ordered the correct fan today that's designed for my 04.
Hopefully this is the issue, and hopefully the new fan will fix it.
The system was run through a machine a before the new t-stat was installed, and again afterwards. It was verified that the air was out of the system, and that there were no leaks. An inferred heat gun reading was done on all hoses, and it shows everything flowing like it should. The t-stat was opening fine, and nothing was clogged or blocked. The belt is also routed correctly, and all hoses are in the correct location.
Now onto my discoveries, and my errors. I notice the clutch had gone a few weeks ago, and brought this up on another couple forums. Members for both forums steered toward the pre 03 Disco's that used a two piece clutch/fan setup. This gave me an pre 03 clutch with a generic Dorman fan blade.
I reached out to Turner Engineering who we purchased the block from, and told them what I was going through. I told them about the clutch/fan setup that we're running, and gave them the part numbers. They came back, and pretty told me that was the issue. Stating that the clutch did not have the capacity that the Rover engine needed, and the the fan was not seated into the shroud correctly. After checking the fan I notice that it needed to be moved forward at least an inch to sit in the shroud. I went ahead and ordered the correct fan today that's designed for my 04.
Hopefully this is the issue, and hopefully the new fan will fix it.
The 03-04 were a 1 piece unit. So the fan blade, and clutch is fixed together as 1 piece. A lot of guys with 03-04 buy the 02 an old because they used a 2 piece unit. Some guys use the severe duty clutch pre 03 D2 clutch, Chevy Express Van clutch, or even an Astro Van clutch. All three of those combined with a 02 an older D2 fan is supposed to work better than the OEM. In my situation it didn't work out.
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Another question. The shop that I had this at said at low RPM's the temps would go up, and once you raised the RPM's the temps would drop back down. Now this was idle, and not when driving. Could this be a water pump issue? The water pump was the only used part that went back on, but it only had about 7k miles on it. The other thing with the water pump is that a lot of people recommend replacing it when you replace your fan. My fan has been removed from this pump at least 4-5 times. I'm wondering if this may have caused the impeller to come loose.
It idles around 210-217 with the 180 t-stat. I think maybe a combination of he incorrect fan, and maybe a worn water pump from the first clutch failure might be the root cause.
Mine idles at roughly 195 to 201 with the 180 tstat.. Ive heard of others with even lower idle temps...
Spent last night swapping the water pump, and fan. The water pump did help some, but not what I was hoping for. At idle in the driveway the temps were 224.7 or 221.6 all the time with the AC on max. When you give it some gas those temps dropped right away to 215.4 to 217.6.
Driving down the highway with an outside air temp of 83 the engine temp ran between 215.7-217.4 with the AC on max. When getting off the highway the temps dropped to 212 on the off ramp, and held at 215.6 at the stop light. The return trip down the highway had the same temps. Driving around town in the 30-40 mph range that temps ran between 212.2-217.6.
After the drive we did some more testing with a heat gun, and thermometer. We put a manual thermometer in the reservoir, and the highest reading it had was 208. It was reading 208 when the UltraGauge was reading 224.7. We shot temps of all hoses, and the upper manifold. The manifold had the highest temps, and that was around 202, and all hoses were under 200. It'll be driven today, and I'm going to get a reading on the radiator itself to see if there are any major swings.
I'm still not 100% convinced the issue(s) are solved. Yesterday was a cooler day being only 83, and I'm still concerned about day that'll be over 90 (next week).
Driving down the highway with an outside air temp of 83 the engine temp ran between 215.7-217.4 with the AC on max. When getting off the highway the temps dropped to 212 on the off ramp, and held at 215.6 at the stop light. The return trip down the highway had the same temps. Driving around town in the 30-40 mph range that temps ran between 212.2-217.6.
After the drive we did some more testing with a heat gun, and thermometer. We put a manual thermometer in the reservoir, and the highest reading it had was 208. It was reading 208 when the UltraGauge was reading 224.7. We shot temps of all hoses, and the upper manifold. The manifold had the highest temps, and that was around 202, and all hoses were under 200. It'll be driven today, and I'm going to get a reading on the radiator itself to see if there are any major swings.
I'm still not 100% convinced the issue(s) are solved. Yesterday was a cooler day being only 83, and I'm still concerned about day that'll be over 90 (next week).
Keep us posted.. I'm dealing with similar issues on a fresh rebuild and need to dig into what the hell is going on..
Those temps are still too high for running a 180 tstat... They are more inline with a stock Tstat
I'm well aware of that.
The only thing left to replace at this point is the coolant sensor. I'm being told that I should take a temp reading of the manifold where the sensor is that there should only be +/-3-5 degrees difference between the manifold and my UltraGauge. After doing this I'm seeing a 10 degree or higher reading.
So maybe I have a faulty sensor, but who really knows. With everything I "thought" was causing the issues nothing has worked so far.
So the 620-112 Fan Blade and Severe Duty Fan Clutch had you idling at 210-217, but the new water pump, and OEM 03-04 one piece Fan Blade/Fan Clutch gives you 221-224? That certainly didn't fix it then. And I remember you saying for sure it's an OEM Grey LR 180F Thermostat right? I'd remove that sucker, sit it into a pot of water and heat that sucker up, monitor it with a heat gun, and see when it opens or if it opens. If that's not the cause then it "could" be sensor related, but you said both were brand new. Have you tried adding a bottle of water wetter or Hyper-Lube's equivalent?