I mean, if it comes right down to it you can go the overkill route; smack in a junk yard radiator and electric fan setup out of a late model Silverado and an in line electric water pump that's way over-rated. That would at least get you on the road without worrying too much. Ain't no kill like overkill, especially with a tight deadline approaching.

I've been wanting to switch to a Silverado radiator for a while anyway. My radiator started leaking a little (put the top screws in too far), but I seem to have staved that off for a while with some epoxy.

 

When I replace a radiator on a D2 the first thing I do is chop 5-8mm off of those lower fan shroud screws!!

 

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).

 

Temp sensors? Are they new? There are two.

 

There are two sensors, and both are new. There's one sensor in the manifold, and a second sensor in the radiator near the outlet on SAI models.

 

Maybe a bad sensor out of the box? Almost sounds like your temp readings are higher than actual. Good luck. I know this is frustrating.

 

That's what we started to think last night. I'm going to get some more reading on it tonight to see what I can come up with.

 

FYI, if you use IR Thermometer directed at manifold where senor resides your reading should close to same +/-3-5 F. IR Temp at my manifold/sensor is -3 F compared to Scangauge.

Has your system ever been properly flushed by removing block drain plugs? I did a drain/flush then used a gallon of vinegar with balance of water and ran it for a couple days to clean system. Completely drained flushed a couple more times. That provided me with my largest drop in temps.

Good luck getting it straightened out.
......

 

I haven't drained the block since this is a brand new engine. The system does not have any air in the cooling system, and this was verified this morning before driving.

Just got a reading from the manifold. It's reading 10 or more degrees higher than the UltraGauge. Is there a good way to test the sensor, or is replacing it the only option?

 

After a long debate last night we've decided to put the Rover on hold. We'll be moving it to our in laws this weekend, and they'll store it for us while we're traveling. We don't plan on getting rid of it just it, but we also need to move forward so we don't jeopardize our travel plans.

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