Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing ?Overheating.

I have several "spare" gauges from old mkII jags in the garage. Made by smiths. Same as my cvh engine moggy. If you need one drop me a pm.

Correct - resistance is different. I cannot find a (very) old post of mine on here with the actual resistance I that I measured. The Ford one therefore gives the wrong readings.

We know how accurate (not) gauges are on Morgans so in my experience if the gauge is not continuing to rise when moving along at a normal speed and there is no coolant loss, steam etc then generally the car is not overheating. Sure the temp may vary (static/moving) but stilll within the designed (Morgan?) temp range. You know you are in trouble if the gauge continues to rise when the car is driving along normally!

Cooling issue Update.


My 200-mile long trip was not uneventful in that coincidentally a radiator hose cracked in a cloud of steam. Easy repair. It seems to have been an original 30-year old hose. Will change them all now.

Apart from that the car didn't seem to overheat and stayed consistently halfway between 90 and 140 on the temp gauge, a little closer to 140 than 90 when stuck in traffic, but came down a little when I started moving again.

However, when I turn the car off, the radiator fan doesn't turn itself off and stays on even when the engine has cooled significantly.

I had to use the electrical master switch to turn off the fan every time I parked.

Diagnosis???

Sticking fan thermostat/relay.
Had the same problem with a Kenlowe on my '76 4/4.

Stuff it on a feed that's only live when the ignition's on. As Graham says suspect the fan controller.

Our 1985 CVH engined car was prone to the fan running after the engine was switched off. It would wait until we had walked around 5 yards away from the car, then turn on. It took a couple of minutes to switch itself off. I put it down to a thermal effect after the engine was turned off. Worth seeing if yours does eventually turn off. They have been known to stick on leaving an unfortunate owner with a flat battery.

I have given up on Morgan Temp Gauges. On all 3 of My Morgans I use Mechanical Temp Gauge purchased from My local Parts Store. The probe fits in the radiator bung. In the +8 Bitsa it one of My 4 gauges. On My +4 I drilled a hole in the dash where I could see it. In the DHC I did not want to ruin the dash so I mounted it on the bar below the dash with strap. I also have Adjustable temp controls on the Fans of two of My Morgans. The probe is inserted into the upper hose. Depending on conditions the fan often runs for several minutes after engine is shut off. So far I have had no problem with the relay. But I can see that they could fail. I also carry an IR temp gauge. So far I lack experience with it, but it is interesting to play with.

The fan on my 2002 Plus8 runs on after stopping the engine if heat soak is high enough. The car doesn't overheat but the fan does kick in in traffic/on stop in summer. The fan used to cut in when the gauge showed 95C. Last week it seemed to cut in closer to 90C. I am wondering if the switch is failing. A new one will be needed just in case.
I'll keep an eye on things as a coolant change is due this autumn anyway so can do both.