I have a question dealing with the 318 in my 64 Fury III. The car has a new aluminum radiator and electric fan. It was cooling decently, only got warm when you got to close to the back of another car in traffic. Lately after an extended trip while going down the interstate it randomly gets hot without anything really in front of it blocking the airflow. It will get hot quickly with something in front of it. I have found that letting off the throttle for a few seconds at a time will cause it to come back down. Almost like burping it. Also, the water pump is not leaking from the weep hole. It also has the coldest thermostat available. What would be causing this? Water pump? Blocked water jackets?
I had an off topic car(so close that I could cry) that had a similar problem. It finally proved to be oiling problems due to a worn out pump. The cooling system was adequate but the excess heat from ring friction overpowered it. So what's your oil pressure?
Check your lower radiator hose for spring inside to keep lower hose from collapsing under high flow. Especially if it cools down when you let off the throttle while cruising.
You didn't say what temp thermostat you're running, but it should be in the 180-195 range. less than that isn't good.
The fan is a single 10 or 12 inch diameter setup as a puller, it sits off to the left alittle from center. It is pulling so I dont have it wired backwards. The radiator has same or better cooling capacity as the original. Its doesnt ping under throttle but does idle a bit low. None Its a universal hose thats not pre-bent so its got a spring in it. If I recall its like a 165. I had some issues with it getting hot at idle previously so this helped it. Please educate me on why this is bad.
How hot is hot? do you have a gauge that reads actual numbers, or are you still using the factory gauge? 220-240 degrees is hot, 210 is not, on a real temperature gauge. The factory electric gauge can show a temp change if the charging system spikes. How fast are you going when it overheats? I've had a bunch of 318 through the years, unless the radiator was plugged enough to effect air flow, the only time they run hot is if you are caring pretty high rpm, a stock 318 probably shouldn't be revved over 5,000 rpm. Normally, if there are no changes that may cause an increase in temp on a gauge that is functioning correctly, a sharp rise, then drop to normal, usually indicates a thermostat that is sticking closed. Things I'd do: 1) Get out the garden hose and wash out the radiator fins. There may be enough blockage of dirt & bug guts to effect the air flow through the radiator. 2) Replace the thermostat, its cheap, it could be the cause of your problem, and you really need a 180 thermostat in there. 165 thermostat takes too long for the motor to warm enough for it to become efficient. The block and heads have to reach a specific temp for the pistons to expand properly. Until they reach that temp, the pistons are not fully round, and do not fully seat in the cylinders, causing blow by and premature cylinder wear. A 180 thermostat will get you to that temp faster then a 165 thermostat will. 3) Get a real temp gauge if you don't have one. 4) Back flush the cooling system. If your not sure when the last time it was backflushed, get it done. The antifreeze tends to break down after several years of service. The crud from the breaking down antifreeze, dust, rust and other contaminates in the cooling system coat the cylinder walls and clog up the water passages in the block and heads causing cooling system problems. The only way to remove the crud is by flushing the system or adding a filtering system to the cooling system. By the way, your car shouldn't get hot coming up on traffic unless your right up against their bumper. Sounds like you need to seal the radiator to the front sheet metal so the air entering the grill has to go through the radiator, instead of around it. Gene
Yup, a 160 will reportedly increase cyl wall wear by 3 times what would happen with a 180-195. Also increases the chances of sludging the engine, especially if you haven't added a PCV valve.
Wow alot of info there thanks. I was running around 65-70 mph, it doesnt have a tac so no clue as to the rpms. The gauge doesnt have numbers, however, in the past when it has been at max hot on the gauge it has pushed water out the overflow. Ive heard about the gauges not being acurate but I feel its giving a decent indication. The fins should be ok but I will check to make sure I will swap the thermostat, good info I didnt know that. One of my ideas was to have it flushed so Im glad I was going in the right direction there. I also considered a shroud of some sorts to do that very thing. Well thats 2 folks with the same answer thats good enough for me. Thanks.
A fan shroud will help around town, but on the highway, there should be enough air flowing through the rad to keep everything happy. What I often see is large open areas between the grill and the rad that will air to go around the rad rather then through it. When the car was built, most of the air that hit the front of the car had to go through the rad. As time progressed, rust, sheet metal being removed, and rubber deteriorating and falling off allowed much of that air to go around the rad instead of going through it. At one time, there was probably a rubber, or rubberized material that fit between the lower bumper and the radiator support, and a rubber flap between the radiator support and the hood. Often one or both of these are gone. Air tends to take the easiest path possible, going over or under (or around) the radiator is easier then going through a rad. Its the same deal with the sides of the rad, if your aluminum rad doesn't cover the entire opening, or isn't right up almost against the radiator support, the air will go around the sides (top or bottom) instead of through the rad. Correcting the air flow in front of the rad by sealing up any area the air can escape is more effective that correcting it behind the rad (with a shroud). Adding a shroud after correcting the air flow in front of the rad makes things more effective at lower speeds or when not moving at all. Gene
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