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Discussion Starter #1
My South Carolina based Verde runs cool most of the time. In winter it is so cool that the heater sucks. But when I stop shut off the engine, the temperature rises. It has boiled on hot summer days. I have had the thermostat out and checked it in a pan of water on the stove. The radiator fans works fine. Any ideas?
Thanks,
Ed Prytherch
79 Spider
88 Verde - in SC
88 Verde - on loan to my son in CO
 

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If it runs too cool then your thermostat most likely does not close well. I have had that condition on so many Alfa V6s I forgot the number.
Jes
 

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Discussion Starter #3
I am more concerned about the temperature rise after I shut off the engine.
Thanks,
Ed
 

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They all do that, though you can't rely on the gauge being correct. You can buy a cheap infrared thermometer to confirm the temperature.

There are directions somewhere to rewire the fan to stay on after turning off the engine.

I'd worry about the cold temp's too. My thermostat would sometimes stick open and other times closed. This wouldn't be a big deal if finding a working replacement weren't so hard.
 

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Discussion Starter #5
I have checked it with an infrared pyrometer. Also boiling coolant is definitely hotter than 212. I will take a look at rewiring the fan relay before next summer.
Thanks,
Ed
 

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But Mad North-Northwest
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You sure your radiator cap is working right and you don't have any connection leaks? Pressure testing or replacing the cap could be an easy fix. If the cap isn't holding pressure that can cause boiling.

Temp going up a bit when the car is shut off is normal. The coolant isn't flowing, there's no air flow, and you get heat from the really hot parts (exhaust) flowing back into the block. Shouldn't boil over if you've got a 50-50 coolant mix and a tight system, though.

Wiring the fan to run after shut off should help a bit, but even without this it should not be boiling.
 

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Discussion Starter #7
I am having a hard time getting a pressure tight seal on the coolant tank. I have tried two different (used) caps and I have tried fitting O rings in the caps, but they still leak. I will try to find a new replacement.
Ed
 

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You could have a headgasket leak. Not mixing of oil and coolant, but a headgasket leak that allows combustion gasses to enter the coolant system. This will pressurize the coolant system (beyond the cap rating) and force the coolant out the cap (as the pressure exceeds the cap rating - note that the cap is supposed to release pressure - 8 psi or so if I recall correctly). There is a simple chemical kit to test for exhaust gasses in the coolant.

Hopefully, it is just a defective cap. It should have the pressure rating on the top.

Jes
 

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But Mad North-Northwest
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If I understand his description correctly it fortunately sounds like a head gasket is unlikely. That would cause overheating during running...sounds like his runs cool but then boils when parked.

One other possibility: when I first got my Milano I got coolant out of the cap sometimes. I was filling the coolant up the the "max" line, which is usually what you're supposed to do.

In the Milano, however, it seems like there just isn't enough expansion space in the tank. It wasn't boiling over, but I was losing coolant out the cap because as the fluid expanded from the heat it would force its way out. I now fill it about midway between the lines and it seems happier.

I seem to remember others having this issue so I don't think it's just me.
 
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