210-215 is ok but when sitting at a light or crawling with the slow pokes it starts climbing. Highway speeds in the heat it sits around the 210 mark.
My Walker radiator keeps my SBC nice and cool. No shroud, special pump, electric fan. My mechanical fan isn’t even in the middle of the radiator !. Don’t know if they’re still available.
thanks for the pics... first thing I would do is get a towel and and drape it over the grille and see if the fan holds it there...second thing is get a temp gun and see what the block temp is....down by the pistons... look for radical changes in temps... good way to check for plugged up block... next, I would hook up the by pass hose from the pump to the maniflod... with out it the water doesn't circulate when the stat is closed and injects too hot of water into the rad. when it opens... another thing is wrong temp thermostat , or not one at all... and I've found this hundreds of times...one that opens too soon, or not one at all runs the water through the rad too fast and it doesn't have time to cool... another thing with a temp gun check to see how accurate the gauge is.... and also check temp at top pan of rad. and at bottom to see what the split is.... also when first started and sitting idling, check for cold spots on the core.... plugged up core on small rad. not good.... take the rad. out, turn it upside down and flush it with a garden hose and see what comes out of it.... good luck...
I am confused about the adage that the coolant can go too fast through the radiator and not have time to cool off. Seems to me it is a continuous flow of water. If the water is moving too fast to cool then the average water temp in the radiator would be high. Heat exchangers are more efficient when the difference between the coolant and air is large. https://www.torq-n-seal.com/why-does-fluid-velocity-matter-in-heat-exchangers/
While the proper fan and shroud are important, as is the proper T-stat and a good radiator, no engine should surpass the stat temp at cruise speeds. Enough air will pass through the radiator. You can use a non-contact thermometer to see if you're getting the appropriate 40-45 degree temp drop through the radiator. If that's ok, then you need to work on the engine getting too hot. Retarded timing and lean mixture both create a lot of heat. Make sure you don't have any vacuum leaks, your plug colors are tan or darker, and your SBC is at 36-37 total timing with 10-14 degrees of vacuum advance functioning properly. You can even experiment with a bit more timing to help cool the motor just in case the marks aren't correct. 99% of the time this little tune-up cools the cars I work on, including one that's approaching 450 hp in a 350, another going together that's 525 in a 400. I also use the "big window" thermostats that start opening around 155 which helps not overshoot the 180 wide-open temp. Even my flathead Ford never runs above 180 stat temps in any weather. Get the timing and fuel mixture right!!!
The one he has will pull air but it needs help from a shroud. I ran one like 19Eddy30 showed in post 23 on my 48 and those are intended for drag racing cars for the most part. Pull just enough air to get back up the return road without getting real hot but don't cause much restriction at full throttle for a quarter mile. That 16x16 radiator core that Pantodd74 has has 256 square inches. That isn't a lot to cool a V8 that size. Still I would create a shroud, maybe even hit the baking pan section of the local thrift stores for a candidate. Maybe just a piece of sheet metal that I could cut a hole in for the fan and bend to have it fit to the radiator and have room to flow between it and the radiator to the fan. It doesn't have to be fancy or pretty to see if a shroud helps solve the problem, just functional and secure. Fancy and pretty can come later.
Good, getting confused by that is the proper reaction of a thinking mind. It is incorrect. A logical conclusion given some facts, but a conclusion based on too few facts leading to it being wrong. What probably happened was that people had engines that just borderline overheated. They come to the great idea to toss out the thermostat, as that should bring the temp down. Even when fully open the thermostat restricts the flow so without it you get faster flow through the cooling system. So, the next time they run it they find out it still overheats, and now it boils even worse - WAY worse! So assuming that faster flow means it doesn't have enough time to do the job comes logically at that point. Unfortunately they missed one big detail. The restriction of the termostat located at the outlet of the engine meant that the coolant pressure inside the engine was quite a bit higher. Higher pressure increases the boiling point. Removing the thermostat reduced the pressure and brought down the boiling point, meaning it starts boiling at a lower temperature than before. The engine that was just borderline overheating before has now gone into full thermal runaway, when all the steam bubbles prevents coolant from properly touching the hot metal, reducing the cooling capacity even further.
So yesterday I ordered the Fastkool water pump from Summit. It will be here tomorrow. We took the roadster to CVS last night which is only about mile and a half from the house. Within a mile the temp gauge showed 180. Then closer it was around 220. Then when parked it was back down to 180ish. I was able to hold my hand on the radiator in the parking lot. So I'm thinking the temp sending unit is bad and needs replaced. When he got home I backed it into the garage and while running put a rag on the front of the radiator and it sucked it right up. Pulled it away and when away from the fan area it was limp. The thermostat is less than a year old. I believe it's a 175 or so. So this weekend I'm gonna pull the radiator and water pump. Turn the rad upside down and flush it out. Reinstall it all and see what happens.
So it was 180, went to 220 and back down to 180? Something isn't jiving here. Did it drop while you were parking? You know the first thing you should do when troubleshooting a heating problem is to verify the temperature.
What is your view on a disc type orifice instead of a thermostat? That’s what I have. Mr. Gasket sells a kit with three different sizes. I put the middle one in.
I find it interesting that with all the smart people here and in the business that there isn't a 'dumb it down' basic formula for XXX HP needs XXX volume of coolant and minimum XXX size radiator. I know that variables like fans, car weight, rad materials and construction, thermostat, RPM operating range and other things can vary this number, but why isn't there a good solid universal rule of thumb? There will always be the guy that wants to shorten the rad profile, run a different fan, have a tight engine compartment, something that skirts the standard, but have we even defined that standard?
You are absolutely correct. The "too fast" theory is an old wives tale that has zero engineering logic. If the fluid goes fast in the radiator, it also goes fast though the block...
Probably because those variables vary way too much. Not easy to create a rule of thumb when most of the variables can turn it completely upside down on their own. Small variations on many variables and the end result will be completely unpredictable. That's an excellent compromise when you don't want/need a thermostat. Just keep in mind that some (particularly "newer") engines have a bypass channel straight from the thermostat back to the pump, when flow to the radiator is blocked the channel to the pump is opened to keep the coolant circulating in the engine only during warm up. That bypass channel has to be blocked off when the regular type thermostat isn't used.
Yes the sending unit is going to be changed. I also have a bottle of VP coolant maddative that I'm going to add to the coolant after the flush. See if that helps at all.
what you need is a temp gun, verify every thing to know what needs to be fixed..and also you need to hook up the by pass hose... the idea, though some don't believe... is to heat up the motor and cool down the radiator... the way this works is to use the by pass hose to circulate the coolant in the block to keep it at an even temp,and as the temp rises, it starts pulling coolant from the radiator. so in order to help the radiator do it's job, the T stat partially opens to start mixing the hot coolant with the cool rad. coolant which in turn cools the temp of the block...running a drag race stat eliminator works if you have everything right and a big enough rad. only going a quarter mile...a lot of times the gauge is off, and depends weather its head temp or manifold temp, motors with no by pass hose will read high on the gauge with the sending unit hooked to the head, and low if hooked to the manifold because the coolent is not circulating to get to an even temp, so it actually is getting over heated by the time the stat opens.. and what happens next is it opens too much and pulls too much cold coolant and slams the stat shut...this problem is verified by watching the gauge go up to 220 , then back down to 160.. if you look at a factory built cars temp gauge it will stay at the same running temp all the time.. then when towing up a hill it will start to rise... the fan will lock up and howl telling you to grab a gear and slow down, failing to do this will get you a side road piss break with the hood up... and just for fact... a 60's Camero with a small block takes 2 3/4 gallons of coolant
The jump is because the by pass is not hooked up and the stat is too low, so what it does is goes from wide open to slammed shut, you want it to open a little bit, and keep the motor at an even temp, and when it closes use the by pass to keep the circulation of coolant in the block.. I'm in the same situation with my 28 woody .. I have no idea where i'm at as I changed every thing...being hard headed and refuse the elect. fan idea.. I'm going the ZIP riser route.. my fan does absolutely nothing, and no shroud at this point...just finished the ZIP mod, and gonna get a better , bigger fan... might even go a clutch fan if there's room...
as you can see, there's a lot still wrong with my set up, but started all over... my rad. is 19 x 19 core 3.5" thick... ZIP riser 16'' flex fan, by pass hooked up, and no shroud.. temp sender hooked to head.. gonna start and run it as is to see where i'm at... new fan and shroud is the future thought... also running the AFCO performance coolant, if nothing else it's bio degradable and ionized water mix... so it won't kill my dogs if it dumps on the driveway
correct, and going through the rad. too fast will make the rad coolant same as the block.. temp, the idea is to dissipate some of the heat... if you take a hot bowl of soup, put it in the freezer then pull it right back out, will it do anything???? or do you think that leaving it in there longer it would cool??? that's where the thermostat comes in.. when working proper it stops the flow of coolant coming out of the block... the ol wives tale comes in to play when people take out the stat.... or drill big holes in it because they have the wrong one.... the engineering of the cooling system is to maintain an even temp in the motor, first let it get to circulated desired temp, and keep it there by slowly adding a cool coolant mixture to the motor...you don't want the coolant to be the same in the motor as it is in the Rad..... that's what happens when the stat is pulled or holes drilled in it.. think of the rad. as a savings account... never pull more than you need out, save it for a sunny day
So this evening when we got back from the in-laws I pulled the front shroud off and upper and lower lines. The fluid that drained out was brown. Now I know that the poor thing has Sat most of it's life. Even after an intake replacement last summer with 1 gallon of 50/50 the rest was still muddy brown. Also the temp sensor is in the intake that I will put in the head instead and get a better reading. The radiator will be flushed tomorrow and I will end up doing a few refills with water and heat cycles and draining the mud before I add normal coolant and the VP stuff.
What will be " better" about taking the temp from one head instead of the cumulative temp of the entire engine ?
Nope. Knock on wood, I’ve never had a cooling issue that wasn’t a bad rad or thermostat. When building cars as a pro, cooling wasn’t an issue. But 210 isn’t too hot for an sbc either or most other OHV engines
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