Quote:
Originally Posted by J91Camaro  what is normal opperating temp for a thirdgen then? i thought 180-220 the normal opperating tempature range on a 305. |
I feel like holding a class called "Cooling Systems 101".
The fuel feedback engines (anything with an oxygen sensor) are equipped with a 195° thermostat from the factory.
This limits the
minimum temperature of the coolant.
They did this for emissions and fuel mileage. The coolant will not begin to flow thru the radiator until this temerature is reached. This is NOT a bad thing. As the temperature of the coolant rises, more flow thru the radiator is needed the more the thermostat opens.
The radiator and the air flow thru it removes the heat.
The thermostat will be completely OPEN at 210°. IF the cooling system is working properly the normal temp of the engine will be between these temps.
If the temp is above 220° (let me say this very slowly) a 160° thermostat (or no thermostat) won't make any more difference than the factory thermostat because they will
BOTH be completely OPEN at 210°.
Yes, thermostats fail. They won't open, they get stuck, or won't close. Taking one out that won't open or won't open completely, will get you home. But that is the only good reason to remove one.
There are plenty of fire-breathing 383's running around with the stock radiator keeping their cool just fine.
Let's talk about cooling systems that overheat at
cruise speeds.
There are
only 4
reasons that this happens.
1: inadequate flow of coolant thru the radiator.
2: inadequate flow of air thru the radiator.
3: too much heat being added by the engine to the coolant. (rare)
4: inefficiency of the radiator to remove the heat with adequate coolant and air flow thru it. (ie: too small) (also rare)
Next we'll list the causes of the above conditions with the most common ones first.
1: Coolant leaving the system (leak or radiator cap not holding pressure). Thermostat stuck (or partial opening). Slipping fanbelt driving water pump. Clogged radiator core coolant flow (scale, rust, stopleak, silicone, etc). Flow path thru bypass hose, heater circuit, etc. that coolant is going instead of thru radiator. Wrong rotation water pump inatalled (serpentine verses v-belt). Collapsed radiator hose.
2: Air dam missing, (fans can only remove heat produced at idle). Bent fins on A/C condenser or radiator core. Radiator air path clogged with dirt.
3: Blocked exhaust (clogged cat/muffler). Pulling the 30 foot trailer with my race car on it, uphill, in August, when it's 100, with the A/C on. Early ignition timing. Fuel mixture too lean. Late ignition timing or malfunctioning engine (have to hold it on the floor to go 50).
4: "Painting" or "Plating" of the inside of the tubes in the radiator core from contaminated coolant or stopleak. Excessive heat load from transmission oil cooler being dumped into coolant. Too much heat being dumped into the airstream before the radiator by the A/C condenser.
Spent all of my money on the "502" and thought I could get by with a stock radiator.
I have left off a few causes. Can you list them?
Next week: How to use a hand-held non-contact thermometer($29) to troubleshoot cooling system problems...
(inside joke) the car runs a whole lot stronger before it was off the tab it was so advanced, my buddy thinks cooler, but im not sure yet, also the black plastic panel under the nose of the car is removed due to damage, i could see about getting another 
