Overheating: problem solved?

[Winter]

Continuing my saga: the radiator has been replaced and a 400-mile round-trip motorway journey with a couple of jams has been a useful test - including 30 or so with a blue paper towel obscuring most of the front grill. The indicated temperature never went above 90. Encouraging.

Traffic in Sheffield elicits 95ish but this soon falls to 85 or so once out in the open. So, considering that the weather is cooler, matters are not completely clear but the signs are good. The old radiator did not look at all bad; three years and 36,000 miles were not characterised by markedly blocked fins and internal galleries were clean.

So, I still don't know for sure. Next summer might be the acid test.

[neal]

Excuse me if I'm stating the obvious, but the thermostat on the V8 opens at 82'C.

But that assumes there plenty of airflow through the radiator. If not the ECM will let the temperature rise to almost 100'C before the fans cut in, the engine cools and the fans cut off around 85'C.

The one cunning way to see if you have a problem is to turn the AC on - that causes the fans to stay on permamently, at least until they would be ineffective - at a speed of say 40mph or above.

So with AC on you should see a steady 82'C regarding of the condtions...

[Winter]

Excuse me if I'm stating the obvious, but the thermostat on the V8 opens at 82'C.

But that assumes there plenty of airflow through the radiator. If not the ECM will let the temperature rise to almost 100'C before the fans cut in, the engine cools and the fans cut off around 85'C.

The one cunning way to see if you have a problem is to turn the AC on - that causes the fans to stay on permamently, at least until they would be ineffective - at a speed of say 40mph or above.

So with AC on you should see a steady 82'C regarding of the condtions...

Thanks Neal but that possibility was eliminated long ago. I have the ac on virtually continuously - much to the dismay of wooly-hatted and be-gloved passengers - and all three fans run.

[neal]

Thanks Neal but that possibility was eliminated long ago. I have the ac on virtually continuously - much to the dismay of wooly-hatted and be-gloved passengers - and all three fans run.

Sorry, it's hard to keep track of of the people (myself included) who are having overheating problems with their V8!

When the engine's overheating, have you felt the hoses running to and from the radiator? These should be piping hot (practically untouchable) but if not it could indicate an air lock in the system [i'm assuming you've checked the thermostat, water pump, etc.]

[Winter]

Sorry, it's hard to keep track of of the people (myself included) who are having overheating problems with their V8!

When the engine's overheating, have you felt the hoses running to and from the radiator? These should be piping hot (practically untouchable) but if not it could indicate an air lock in the system [i'm assuming you've checked the thermostat, water pump, etc.]

Sorry, it's hard to keep track of of the people (myself included) who are having overheating problems with their V8!

When the engine's overheating, have you felt the hoses running to and from the radiator? These should be piping hot (practically untouchable) but if not it could indicate an air lock in the system [i'm assuming you've checked the thermostat, water pump, etc.]

Yes, all checked long ago.

[paulhavelock]

Just as a point of encouragement, I had overheating probs with my '98 V8, but once I had put in a new rad (old one leaking) and found all the other leaks (corroded ali heater take off pipe at the front and ali manifold at rear of engine) my car now runs perfectly at 82degC unless in traffic, where it oscillates between 95degC and 100degC as the fans cut in and out, just as the workshop manual states it should. You'll be fine.

Cheers,

Paul H